June Updated Forecast for the 2022 Atlantic Hurricane Season

20 06 2022

Dale C. S. Destin |

My June updated forecast for the 2022 Atlantic Hurricane Season is out, and it continues to call for a very busy and active season with the potential of being super hyperactive. As of June 20, the forecast is for 20 named storms, 10 hurricanes and 4 major hurricanes.

Recall that the accumulated cyclone energy index (ACE) is the universally accepted metric used to classify the overall activity of a hurricane season. The ACE forecast for this year is 186, 34 above the threshold for an active season, based on 1991-2020 data.

A super hyperactive season like 2017 also remains possible. There is a 37 percent chance of the ACE exceeding 223. Further, there is a 43 percent chance of more than 19 named storms; 24 percent chance of more than 11 hurricanes and also a 22 percent chance of more than 6 major hurricanes.

If the forecast pans out, this season would be the tenth most active, on record, in terms of ACE, dating back to 1851. It would also tie with 1933 for the fourth highest number of named storms.  

Recall, a typical season, based on the new standard climate period 1991-2020, has 14 named storms, 7 hurricanes and 4 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), according to the Saffir Simpson Hurricane Wind Scale.

The Atlantic hurricane season officially goes until November 30.

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Updated Prediction: Below Normal Rainfall Most Likely for Antigua for 2022

31 05 2022

Dale C. S. Destin |

The prediction for rainfall remains discouraging. My latest forecast continues to call for most likely below normal rainfall for Antigua. The most likely total for the year is 1080 (42.5 in), down 25 mm (1 in) from the previous forecast. There is also a 70 percent or high confidence of the rainfall total falling in the range of 590 to 1695 mm (23.2 to 66.7 in).

The main reason for the below normal rainfall forecast is the current trend of cooler than average sea surface temperatures (SSTs) across the tropical North Atlantic (TNA), which should last through summer (June-August). Cooler than normal TNA SSTs favour suppressed rainfall conditions while the opposite enhances rainfall.  

The year started out with a severe drought brought forward. This drought started in the winter of 2020/2021 and continues through the present. This May has been wetter than the last one; notwithstanding, it will end with well below normal rainfall. Year-to-date is drier than normal. Further, since the deluge of November 2020, the start of the current drought, there has been 943.1 mm (37.13 in) of rainfall, for December 2020 to May 2022. This total is so far below normal that it is the second driest such period on record.

The dry season, January to June, is on track to be drier than usual. Summer, June to August, is also likely to be drier than normal. Further, the first three quarters of this year (January to September) is likely to see deficit rainfall with a most likely total of 645 mm (25.4 in) compared to the usual amount of  759 (29.9 in). There is also a 29 percent chance of January to September having top 10 dryness.

WMO Lead Centre for Long-Range Forecast Multi-Model Ensemble is forecasting 40-50% likelihood of below normal rainfall for Antigua and Barbuda for June to August. Also, below normal rainfall is likely for much of the rest of the Caribbean.

A typical year, based on the new standard climate period 1991-2020, averages 1156.7 mm (45.54 in). The dry season averages 410 mm (16.14 in) and the wet season, July to December, averages 746.8 mm (29.40 in). The fall/autumn, September-November, accounts for 58 percent of the wet season total and 38 percent of the year’s total.

This forecast will be updated monthly around the 25th of each month until August. The next update will be issued around June 25.

Regardless of the forecast, we all need to conserve water and be as efficient with its use as much as possible. Reducing our personal water footprint will literally redound to our individual and collective socio-economic benefit. Minimising your water footprint is also good for the climate, good for our environment and good for rainfall.

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Wet Weekend for the Northeast Caribbean

28 04 2022

Dale C. S. Destin |

A trough system is poised to cause wet weather across the northeast Caribbean, including Antigua and Barbuda. Several of the more reliable weather models are forecasting the potential (10 percent chance) for rainfall totals exceeding 25 mm (over 1 in) to fall over the period Friday to Sunday of this weekend.

The potential total for over 25 mm in 72 hours is not in and of itself a high figure. However, relative to April and the fact that we are in a severe drought makes this worth “writing home about”.

Whereas all models consulted are forecasting rainfall for the weekend, the forecast totals differ, as can be expected. At the lower end of the potential rainfall scale some are projecting a 10 percent chance of over 25 mm (over an inch), while others are suggesting potentially higher totals, a 10 percent chance of over 75 mm (3 in) for the weekend.

GFS 24hr precipitation total exceedance forecast probabilities showing all areas with at least a 10 percent chance of getting over 50 mm (2 in) of rainfall from 2 am Saturday, 30 April to 2 am Sunday, 1 May 2022

The wet weather is expected from Dominica to Hispaniola. The highest totals are likely across Puerto Rico and the Virgin Islands Saturday/Sunday. Most of the rainfall for Antigua and the rest of the Leeward Islands is likely Friday/Saturday and for Hispaniola Sunday/Monday.

If the models prove right, and the upper end of the rainfall potential materialises, some places across the northeast Caribbean could see the average total for April falling in one weekend, if not one day. The possible rainfall total for the area is 25 to 100 mm (1 to 4 in). With this kind of rainfall possible, depending on the intensity and duration, flash flooding and associated impacts are of concern.

Deterministic rainfall accumulation forecast by the GFS model from Thursday, 28 April to Sunday, 1 May 2022

The rainfall of this weekend could, at least, put a dent or further dent in the droughts across the area, particularly the Virgin Islands and Puerto Rico. It will certainly have a big impact on domestic catchments, temporarily easing the stress and demand on water resources authorities.

There is no doubt that these showers will be welcome by all; however, they could prove disruptive to weekend plans leading up to Labour Day Monday celebrations. Good news though: The weather should just about be back to normal by Monday.

The system has already caused wet weather across the southern Caribbean with some areas receiving over 75 mm (3 in). The trough also prompted flash flood warnings for some islands.

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Early Prediction: Very Busy 2022 Atlantic Hurricane Season Forecast

14 04 2022

Dale C. S. Destin |

This hurricane season will likely be another very busy one, exhausting the primary list of named storms, once again. My early forecast for the 2022 Season is out, and it calls for 21 named storms, 9 hurricanes and 4 major hurricanes.

In addition to being a very busy season, it is most likely to be an active season. Recall that the accumulated cyclone energy index (ACE) is the universally accepted metric used to classify the overall activity of a hurricane season. The ACE forecast for this year is 182, 30 above the threshold for an active season, based on 1991-2020 data.

A super hyperactive season is also possible. There is a 36 percent chance of the ACE exceeding 223. Further, there is a 49 percent chance of more than 19 named storms; 30 percent chance of more than 11 hurricanes and 29 percent chance of more than 6 major hurricanes.

If the forecast pans out, this season would be the third most active since 2017, in terms of ACE, and the tied with 1998 for the 10th most active on record dating back to 1851. It would also tie 2021 for the third highest number of named storms.  

According to other forecasts surveyed, the consensus is for an ACE of 161, 19 named storms, 8 hurricanes and 4 major hurricanes, a busy and active season. This is generally consistent with my forecast but with a notable 21 less ACE. However, regardless of the forecast, you should always be well prepared each season, as it only takes one hurricane to ruin your year and or life.

The main reason for the above normal forecasts is the current La Niña, which should last into the first half of the hurricane season and maintain favourable conditions for tropical cyclone formation even beyond August, into the peak of the hurricane season.

A typical season, based on the new standard climate period 1991-2020, has 14 named storms, 7 hurricanes and 4 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), according to the Saffir Simpson Hurricane Wind Scale.

The last Atlantic hurricane season–2021, will be most remembered for being a very busy season with 21 named storms. Collectively, the season caused 103 deaths and over US$80 billion in damage. Major Hurricane Ida alone caused 55 deaths and over US$75 billion in damage.

This forecast will be updated monthly around the 14th of each month until August. The first update will be issued around May 14.

The Atlantic hurricane season officially begins on June 1 and concludes on November 30; nevertheless, in the last six years, there have been preseason tropical cyclones–be prepared!

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Drier than Usual January for Antigua

23 02 2022

Dale C. S. Destin |

January 2022 was another drier than usual month for Antigua; the fourth in a row and the 10th since January 2021. The month registered just  48.3 mm (1.90 in), making it the fifth January of the last eight with below normal rainfall.

January usually clocks 67.3 mm (2.65 in) of rainfall annually (1991-2020); this means the month fell close to 28 percent below its usual total. This is an improvement over January 2021, when the deficit was close to 60 percent. Notwithstanding, it is another year with a bad start.

January’s rainfall anomaly (deviation from normal) in percentage (blue line) along with the long-term trend (grey broken line). The background is that of Potworks Dam, 3 February, 2022

The rainfall for January continues to trend negatively (downward); however, this trend is statistically insignificant. The trend is at a rate of just 0.16 mm (0.0064 in) per year or 16 mm (0.64 in) per hundred years. This also represents an insignificant rate of 0.24 percent per year or 24 percent in 100 years. No evidence of a changing climate with respect to rainfall in January.

In aggregate, the three-month period ending January is among the driest on record going back to 1928. The total of 141 mm (5.55 in) is the third lowest behind November-January of 1967/68 and 1947/48. The last four, five, six and seven-month periods ending January had record-breaking low rainfall. Further, the last year (February to January) ranks second driest, on record, with 621.5 mm (24.47 in). The record is 588 mm (23.15 in), February 2015-January 2016.

Clearly, we remain in the grips of a severe meteorological drought, which is also defined as exceptional by some other metrics. Also evident are agriculturalhydrologicalecological and socio-economic droughts, at varying intensities. Potworks Reservoir remains 100 percent empty, converted into a pasture for grazing animals. All other surface catchments are in a similar state or below extraction levels.

Antigua Public Utilities Authority (APUA), the country’s water resource manager, has just commissioned a new reverse osmosis plant to obtain more potable water from the sea. This should bring the daily total from this source to over 7 million and it should help to ease the water woes. However, the drought continues to be a very serious matter for many, who are forced to go days without potable water, as demand continues to outstrip production by hundreds of thousands of gallons.

The drier than usual start to the year was not confined to Antigua. Much of the Caribbean Basin experienced below normal rainfall with some islands or part thereof getting less than 25 percent of their usual total–75 percent rainfall deficit or more.

CMORPH 1-Month Percent of Normal Rainfall for January 2022

Drought conditions have worsened across a number of the other islands, including the rest of the Leeward Islands, the Virgin Islands and Puerto Rico, most of the Windward Islands and Barbados. The Caribbean Institute for Meteorology and Hydrology (CIMH) has recommended drought watches or warnings for most islands of the Caribbean.

It is unclear as to when there will be any notable respite from the drought. The latest set of models surveyed suggests an equal chance of below, near or above normal rainfall for March to May for Antigua and Barbuda and much of the rest of the Caribbean.

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Near Record-Breaking Dry Year, Drought Reigns

18 01 2022

Dale C. S. Destin |

It was a near-record-breaking dry year (2021) for Antigua. The year produced a measly island-average rainfall of 600.7 mm (23.65 in), the second lowest on record behind 2015 with 574.5 mm (22.62 in). Officially, 2021 was easily the second most parched year in a series from 1928 and unofficially, since, at least, 1871.

The yellow broken line represents the rainfall anomaly trend, which indicates no significant change to wet (positive) or dry (negative) anomaly.

It was a year reigned by drought from beginning to end, and the reign is likely to go on through the upcoming months. The drought has a firm grip on the weather, being at the most intense category: severe, exceptional by some other standards. The normal annual total is 1156.7 mm (45.54 in), nearly twice the amount measured for 2021.

The rainfall deficit amounts to a whopping 556.0 mm (21.89 in) or 48 percent of the usual total for the year. This is more than the average for the first seven months of a year. Every month accrued a shortfall with the usually wettest month of the year–November, accounting for over 22 percent of the overall rainfall shortage.

This level of waterlessness for a year is extremely rare. There is only a 0.5 percent chance of the island-average being 23.65 inches or lower. This translates to the kind of dryness that has a return period of once in 200 years (1-in-200 years), on average.

Alternatively, there is less than a 10 percent chance of such harsh weather reoccurring in the next 20 years. One is, at least, twice as likely to see a hat-trick in a cricket match than experience the likes of such lacklustre annual rainfall.

268Weather accurately predicted a drier than usual year was likely. As early as May 2021, we indicated a 46 percent chance of below normal rainfall. The chance rose to 58 percent in June and peaked at 61 percent in August. There was also a peak of 19 percent for the year to rank among the top 10 driest.

The usually wettest consecutive pair of months, October-November, almost literally produced a speck in the bucket. The frequently rainiest duo was the record driest with the trivial amount of 63.8 mm (2.51 in) with each month recording less than an inch-and-a-half of rainfall for the first time, on record. Combined, the shortfall for the months accounted for 45 percent of the year’s deficit. The previous lowest for this period was 89.7 mm (3.53 in), in 1983.  

The last quarter (October-December) was also the driest on record, dating back to 1928. The total of 127.3 mm (5.01 in) shattered the previous record of 143.0 mm (5.63 in), for the last three months of the year, set in 1983. Usually, this period precipitates 397.5 mm (15.65 in), over thrice what actually fell.

It was essentially a year without a wet season (July-December). The dry season pretty much went on and on, for the whole year, resulting in a record-breaking dry wet season. The season’s total of 396.0 mm (15.59 in) retired the previous driest wet season of 1983, which accumulated 405.6 mm (15.97 in). Cumulatively, the third and fourth quarter rainfall represented just 53% of the normal amount of 746.8 mm (29.40 in). A typical dry season (January-June) averages more rainfall than occurred for the 2021 wet season.

While the island on a whole had near-record-breaking low rainfall, parts of the country actually had record dryness. Coolidge, in northeast Antigua, had a record low rainfall of 469.6 mm (18.49 in), crushing the previous record of 554.0 mm (21.81 in) set in 2015. This represents only 47 percent of the normal annual total of 1000.8 mm (39.40 in). This kind of rainfall scarcity occurs only once every 333 years, on average, or a less than 10 percent chance of occurring in the next 35 years or the next generation.

It is unclear as to what was responsible for this nearly unprecedented dryness. The usual culprit: El Niño was not only absent but his sister: La Niña, usually the rainmaker, was present, yet to little avail. The dryness may have been mainly the result of a consistent stream of dry and dusty air from the Sahara Desert along with a cooler than usually tropical North Atlantic.

There is the saying: “If rain does not fill a [water] drum, dew is not going to fill it.” Meaning, if the wet season did not end the droughts, particularly the hydrological and socioeconomic ones, how can the dry season, which we are in, do so? It can’t; hence, the sufferation from insufficient rainfall could continue through the next six months.

The last 10 years have been the driest decade for Antigua. Five of the last 10 years have had below normal rainfall with 2015 and 2021 ranking one and two, on record. Only one year (2020) has had above normal rainfall since 2011.

Other Caribbean islands are having similar challenges with rainfall or lack thereof. For example, the Henry Rohlsen Airport in St. Croix was said to be on track, in December, to record its third driest year, on record dating back 58 years. A number of other parts of the Caribbean were also on the way to record rainfall ranking among the top 10 lowest.  

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Near Record Driest November for Antigua

7 12 2021

Dale C. S. Destin|

Most Antiguans alive have never endured a November like the just ended one. The month was second driest on record, dating back to 1928. It registered a near record breaking 29.2 mm (1.15 in) of rainfall, the lowest since 25.1 mm (0.99 in) in 1947, almost 75 years ago. This very rare November rainfall event has around a 0.7 percent chance annually or once every 143 years, on average.

November usually logs 152.1 mm (5.99 in) of rainfall annually (1991-2020); this means that only a little over 19 percent of the usual total fell this year. The deficit of 81 percent is the second worst for the year, behind May with 83 percent. November is usually the wettest month of the year.

The absentee rainfall for November has virtually ensured that 2021 will be among the top eight driest, on record. Although unlikely, this year could even break the record for the driest year set by 2015, when just 574.5 mm (22.62 in) rainfall was accumulated.

Thus far, the total for 2021, through November, stood at 537.2 mm (21.15 in). Normally, this period yields 1059.2 mm (41.7 in); hence, there is close to a 50 percent shortfall of rainfall. Less than 37.3 mm (1.47 in) of rainfall for December would see the record fall. Such low annual rainfall is extremely rare. The chance of this meagre annual total is less than 0.2 percent. This translates to a 500-year event or worse, an event with a return period of once every 500 years or more, on average.

November has also virtually sealed the fate of the wet season (July-December). It is certain to be among the driest, if not the driest, on record. The current record is 405.6 mm (15.97 in) for the 1983 wet season. Thus far, July-November, the total for the 2021 wet season is 332.5 mm (13.09 in).

While it is possible that the rainfall for the wet season will be at a record low, the rainfall for the last seven months ending November was in fact record breaking. No other May-November has been drier, on record going back to, at least, 1928. The total of 405.4 mm (15.96 in), for this year, eclipsed that of 406.4 mm (16.00 in) observed in 2015.

It goes without saying that serious meteorological drought continues, and it is highly likely to get worse, in the short-term. Also evident are agriculturalhydrologicalecological and socio-economic droughts, at varying intensities. Potworks Reservoir now has ZERO drop of water. All other surface catchments are in a similar state or below extraction levels.

Potworks Reservoir with zero drop of water – December 2, 2021. Picture courtesy Karen Corbin, Humane Society

Antigua Public Utilities Authority (APUA), the countries water resource manager, informed the public yesterday that 95 percent of all potable water, being produced by the organization, is desalinated water from the sea. We were also informed that the total water production of six million gallons per day is, at least,  a million gallons below the country’s daily requirement; hence, water is being rationed.

With such lean rainfall figures and with the recent conclusion of COP26, the obvious question would be: Was this caused by anthropogenic (human induced) climate change? From my reading of the latest IPCC report and other papers, the answer is no. According to the report, there is a low confidence in the change in agricultural and ecological droughts in the Caribbean, thus far. However, the long-term projection is for an increase in the intensity and frequency of droughts, but this will not be for all regions. Unfortunately ,the Caribbean is likely to be among the regions to bear the negative changes.

Whereas climate change is unlikely to have been a factor in November’s rainfall, or lack thereof; it was noted that suppressing rainfall conditions prevailed across the area for much of the month. Strong positive velocity potential anomalies caused sinking air, which is prohibitive to cloud growth and hence rainfall. The velocity potential is associated with the Madden-Julian Oscillation (MJO) with positive values being indicative of the dry portion of it.

Three-day centred average animation of daily IR and 200-hPa velocity potential anomalies (base period 1991-2020). Velocity potential anomalies are proportional to divergence with green (brown) contours corresponding to regions in which convection tends to be enhanced (suppressed).

This extreme dryness for November was not endured by Antigua only. The unusually low or near record breaking rainfall was observed across much of the Eastern Caribbean. For example, reports out of Trinidad and Tobago indicate that much of the country had its second driest November, on record.

November was the last hope for the replenishment of national surface catchments, this year. With the very disappointing rainfall, the next possible time for replenishing precipitation is May. The issue with insufficient potable water is likely to get worse before getting better.

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Third Busiest Hurricane Season Ends

1 12 2021

Dale C. S. Destin |

The third busiest Atlantic hurricane season–2021, ended yesterday. The season produced 21 named storms, the third highest on record, behind 2020 with 30 and 2005 with 28. The season also produced 7 hurricanes, tied for 32nd highest on record dating back to 1851. Further, there were four major hurricanes, Category 3 and over, which tied for the 18th highest on record. Thirty-two other seasons had seven hurricanes and 18 others had 4 major hurricanes.

Although the most eye-catching statistic for a given season is the number of storms, this is not the metric used to determine its overall activity. The Accumulated Cyclone Energy (ACE) index remains the internationally accepted metric used to categorize the activity of a season. The ACE takes into consideration not only the number of named cyclones but also their strength and duration. Hence, based on the ACE, 2021 is the 29th most active hurricane season on record, with an ACE index of 142.

The most active hurricane season on record remains 1933 with an ACE of 259, 44% more than 2020, the record busiest season, w.r.t. the number of named storms, NOT ACE. The 1933 season was also over 80% more active than 2021. Thus, notwithstanding the headline-grabbing 21 named storms for 2021, the season was nowhere close to being the third most active. Activity has to do with the ACE, while busyness has to do with the number of named storms.

Based on NOAA’s classification, the 2021 season was above normal. However, NOAA’s classification of season has its challenges, allowing for one season to simultaneously have two classifications. Also, NOAA uses the 1991-2020 period the define an average season but uses the 1951-2020 period to determine if season is normal or not. A better approach is to classify seasons strictly by the ACE index, as does by 268Weather. This approach categorises the 2021 season as near normal; based on the 1991-2020 climate period, the 2021 ACE of 142 falls in the middle tercile. An average season produces 14 named storms, 7 hurricanes, 3 major hurricanes and ACE of 123.

268Weather’s seasonal hurricane forecasts fairly accurately predicted the number of named storms and major hurricanes. However, we did not do as well with the other parameters, particularly the important ACE index. Based on the number of named storms, the ACE is unusually low. This is largely because of the record high nine shorties–storms lasting two days or less. Notwithstanding, tropical cyclone metric forecast by 268Weather fell within the 70% confidence. Interestingly, as little as 30 years ago, most of these shorties would have gone undetected, resulting in the official numbers being significantly less.

As busy as the season was, thankfully, Antigua and Barbuda along with the rest of the Leeward Islands and the British Virgin Islands were spared. Officially, the record will likely say that we were impacted by Tropical Storm Grace; however, this system bought ZERO storm-force winds to our shores.

The season got off to an early start with Tropical Storm Ana on May 22 and closed early with the dissipation of Tropical Storm Wanda on November 7. After flurry of storms from mid-June to mid-July, ending with Elsa (July 1-14), the season went on a bit of a hiatus until August 11, when Tropical Storm Fred formed. In less than one-and-half month, from August 11 to September 29, 15 storms formed, more than the average for a season. October went virtually stormless except for the eleventh-hour development of Tropical Storm Wanda on October 31, exhausting the 21-name Atlantic list.

The most powerful cyclone for the season was Category 4 Major Hurricane Sam, which had peak sustained winds of 250 km/h (155 mph). Sam did not make landfall; hence, it caused minimal impact.

The most deadly and destructive system was  Category 4 Major Hurricane Ida, which had peak sustained winds of 240 km/h (150 mph). It killed 115 persons and caused over US$65 billion in damage, becoming the sixth costliest Atlantic tropical cyclone on record. It impacted mainly the Cayman Islands, Cuba and the Gulf and East Coasts of the United States.

A couple notable records for the season:

  • Elsa became the earliest 5th Atlantic named storm on record when it was named July 1. The previous record was set by Edouard on July 6, 2020.
  • 2021 tied with 2007 for the most shorties (storms lasting <=2 days), on record.  
  • 2021 marks the first time of back-to-back exhaustion of the list of Atlantic named storms.

The 2022 hurricane season will officially begin June 1 and 268Weather will issue monthly forecasts starting early April.

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Twin Anniversary of Hurricanes Irma and Luis, where do they Stand Among the Worst Hurricanes to Impact Antigua and Barbuda.

6 09 2021

Dale C. S. Destin |

They both struck on September 5-6 after traversing over the warm waters of the Tropical North Atlantic. Twenty-six years to the day Hurricane Luis (1995) almost totalled Antigua and Barbuda; twenty-two years later, four years ago, Hurricane Irma (2017) did similarly to Barbuda.

Twenty-six years to the day Luis overwhelm our islands, with the centre partially passing over Barbuda and within 25 miles (40 km) of Antigua. Four years ago today, the date of Irma evoked memories of Luis, but it was no Luis.

Irma set a virtually unreachable bar for strength, but Luis set the record for size and cost. Luis was a great big giant while Irma was a mighty midget. The diameter of Irma’s hurricane-force winds was less than 75 miles (121 km) with a radius of less than 25 miles south of the centre. Contrastingly, the diameter for the hurricane-force winds of Luis was at least twice Irma’s, over 150 miles (241 km), with the hurricane force-wind extending about 50 miles (80 km) to the south.

Hurricane Irma on Sep 5 (top) and Hurricane Luis on Sep 3 (bottom) via NOAA satellites

Strength matters but clearly size matters more. Although both hurricanes took a similar journey through the area, Luis caused hurricane-force winds to reach both Antigua and Barbuda, whereas none reach Antigua from Irma. While in our neck of the woods, Luis had peak sustained winds of 140 mph (225 km/h) and Irma had 180 mph, 129% the strength of Luis but about 50% its size. This is what saved Antigua from the Category 5+++ wrath of Irma.

The actual paths of Hurricanes Irma and Luis courtesy NOAA Historical Hurricane Tracks

Antigua and Barbuda has been impacted by 14 major hurricanes, passing within 69 miles (111 km), on record dating back to 1851. There have been four in the last 26 years–Jose and Irma 2017, Georges 1998 and Luis 1995.

Meteo-France radar image showing the eye of Hurricane Irma passing over Barbuda, about 25 miles north of Antigua, 1:15 am (05:15 UTC) Wednesday Sep 6, 2017

A hurricane that compares well with Irma and Luis is Dog of 1950. Dog, also known as “the great hurricane of the central Atlantic”, came through as a Category 4 hurricane with wind of 130 mph (209 km/h). Its centre passed within 10  miles (16 km) of Antigua and within 15 miles (24 km) of Barbuda. Its powerful eyewall would have impacted both islands, like Luis 45 years later.

Prior to Luis, Dog was considered the most severe hurricane on record in Antigua and Barbuda. The damage caused by Dog amounted to up to US$1 million. In today’s currency, that is equivalent to US$8 million, paling in comparison to the US$100 to US$350 million (US$216 to US$755 million 2021) caused by Luis. Dog’s damage also pales in comparison to that of Irma’s US$136 million (US$153 million 2021). Total damage and loss from Irma were about US$155 million (US$174 million 2021).

Downtown St. John’s, Antigua with piles of galvanize

Irma ranks as the strongest hurricane to pass within 69 miles of Antigua in the record books, which dates back to 1851. Luis ranks sixth and Dog ranks seventh. Interestingly, 9 of the 14 major hurricanes passing less than 70 miles of Antigua and Barbuda occurred in the pre-climate change era–1980. The second and third strongest were in 1899 and 1928 respectively.

Major hurricanes to pass within 69 miles of Antigua and Barbuda 1851 to 2021. Multiply by 1.61 to get km/h
NOAA satellite image showing Barbuda in the eye of Irma 1:45 am (05:45 UTC) Wednesday, 6 Sep 2021

Congratulations to all who survived these hurricane nightmares, which I hate to call anniversaries. Let’s hope we don’t see another Luis or Irma-like major hurricane, which is perhaps wishful hoping. More realistically, let us prepare as much as possible to be hurricane strong i.e. hurricane resilient, so that we are able to put up a better fight to resist the next hurricane be it major or not.

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Correction: In the original blog post published on September 6, 2021, I mistakenly calculated the current day value of the damage and loss caused by Hurricanes Dog, Luis and Irma. I updated the post to fix the mistakes on September 13. Apologies for the miscalculations.





Wettest Month of the Year, Serious Drought Continues

21 07 2021

Dale C. S. Destin |

June has become the only month of the year, thus far, to clock over two inches of rain. This makes it esaily the wettest month of the year, to date; notwithstanding, serious meteorological drought continues for Antigua. The rainfall for the last six months rank among the worst on record. Despite the prayers for rainfall, the heavens look set to provide only sparing amounts, over the upcoming months.

Potworks Reservoir, Bethesda, Antigua, on the verge of becoming totally dry – July 7, 2021. Picture courtesy Karen Corbin of the Humane Society

The rainfall for June was 55.6 mm (2.19 in), the highest for the month since 2017, when the country had 84.8 mm (3.34 in). Notwithstanding, despite being the only month thus far with more than two inches of rain, relatively, June had near normal rainfall with the amount being below the month’s average of 68.1 mm (2.68 in).

Despite being the wettest month, so far, June continues to be the only month that is deemed to have a statistically significant drying trend, i.e. June has gotten drier over the years. The month went from a peak average of 98.6 mm (3.88 in) over 1931-1960 to a minimum of 55.6 mm (2.19 in) over 1971-2000, rebounding to 68.1 mm (2.68 in) over the last 30 years, 1991-2020.

The period April-June was very dry. The total of 111.8 mm (4.40 in) was the fourth driest since independence, 1981, and the eleventh lowest rainfall received for April-June, on record dating back to 1928. Interestingly, April-June 2020 was drier with 78.7 mm (3.10 in).

We continue to witness one of the driest years on record. The just ended dry season, January-June, is the fifth driest on record and the driest since 2015. The last six months yielded only a paltry 204.7 mm (8.06 in), only half of the usual rainfall of 410.0 mm (16.14 in). Just four other years have had a drier first half: 2015, 2001, 1977 and 1939. The record driest dry season is held by 2001 with 130.0 mm (5.12 in).

Our last wet month was November. It flooded severely across parts of the islands; however, the beneficial rainfall is becoming a distant memory, as indicated by our drying and empty catchments. Since November, the last seven months, December-June, was the sixth driest on record and the lowest since 2015. The period has only yielded 58 percent of normal rainfall. Our starving landscape and parched grounds continue to bear witness to the absent rainfall.

The upcoming season, August to October, is likely to see us continuing to suffer from a dearth of rainfall. The majority of models are forecasting the continuation of scarce rainfall. Hence, the drought is likely to continue. Our largest catchment, Potworks Reservoir, along with others, are trending toward becoming dry land, again.

WMO Lead Centre for Long-Range Forecast Multi-Model Ensemble is forecasting 50-60% likelihood of below normal rainfall for Antigua and Barbuda. Also, below normal rainfall is most likely for much of the northern islands.

Based on models which correlate our sea surface temperatures, across the tropics, with our rainfall, the medium and long term continue to look brown. The year will most likely remain drier than usual with a 50 percent chance of below normal rainfall; this is down 8 percent from last month.

As the meteorological drought goes, so go the other droughts: agricultural, hydrological and ecological. There is also the growing concern that this may precipitate a socio-economic drought, if it has not already done so. Our utilisation of the ocean around us for fresh water has made us resilient; however, at a very high cost, as potable water from this source cost at least seven times that from surface and ground water, I am told.  

In the last month, Potworks Reservoir fell below extraction levels, along with most other surface catchments, except for Donnings Reservoir, according the Antigua Public Utilities Authority (APUA), the country’s water authority. With the rainfall outlook bleak, we could be out of all surface water in weeks. Water rationing is imminent, if not already occurring.

Antigua is not alone in experiencing significant rainfall shortages. The countries around us remains  thirsty for rainfall. Deficit rainfall is occurring across the rest of the Leeward Islands, and it is probable that it will worsen, over the upcoming months before improving, based on recent forecasts.

Please continue to follow me for more on this evolving drought and all things weather and climate via TwitterFacebook and Instagram. Also, share this blog, if you found it useful. 





July Updated Forecast for the 2021 Atlantic Hurricane Season

12 07 2021

Dale C. S. Destin |

Category 1 Hurricane Elsa going through the southern Caribbean July 2, 2021.

Not the potentially stressful news anyone wants to hear, but it is what it is; the 2021 hurricane season could challenge the numbers of the 2020 record breaking season. My updated forecast for the Season is out, and it continues to call for an above normal season being pretty much expected. The confidence of an above normal season has increased to 79%. It is also possible that the season could be super hyperactive or well above normal, with numbers reaching the top 10 percentile 1991-2020 base period, which would also be top 8 of all times, dating back to 1851.

The prediction is now for 24 named storms (subtropical storms, tropical storms and hurricanes), with a 70 percent confidence or high confidence of the number ranging between 18 to 31. It is also very likely–74 percent chance (up 18), that the number of named storms will exceed 19 and be in the top 4 seasons of the historical record, dating back to 1851.

My forecast also calls for an accumulated cyclone energy (ACE) index of 191 (up 5) with a high confidence of the range being 119 to 288. Also predicted are 10 hurricanes (up 1) with a 70 percent confidence of  the total being 7 to 14, and 5 major hurricanes (unchanged) with high confidence of 3 to 7.

The season could not only be above normal but well above normal or super hyperactive. There is also a 45% chance of the ACE exceeding 223, the top 10 percentile of the 1991-2020 base period. Further, there is a massive 74% chance of more than 19 named storms or the number of named storms reaching the top 10 percentile. There is also a 45% chance of more than 11 hurricanes and 44% chance of more than 6 major hurricanes.

If this forecast pans out, this season would be the most active since 2017, in terms of ACE, and the 10th most active on record dating back to 1851. It would also be ranked third for the highest number of named storms and tied for 9th for the most hurricanes and major hurricanes respectively.

If the season turns out to be hyperactive, as is possible, it will rank even higher. Only seven seasons have had a higher ACE than 223; three seasons with more than 19 named storms; four with more than 11 hurricanes and two with more than 6 major hurricanes.

Already, the season is off to a “flyer”. Already, there has been five named storms (close to four times the average to date) and one hurricane (close to three times the average to date) . The ACE to date is 12.8. In other words, year-to-date, there is normally 1-2 names storms, instead of 5; 1 hurricane every three years and ACE of 4, as opposed to 12.8, which is over three times the normal rate, up to this point in the season.

The main reasons for the above normal forecasts are the likely above normal sea surface temperatures across the tropical North Atlantic Ocean and a weak La Niña conditions and or a cold-neutral El Niño Southern Oscillation (ENSO) during August to October–the peak of the hurricane season.

A typical season, based on the standard climate period 1991-2020, has 14 named storms, 7 hurricanes and 3 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), according to the Saffir Simpson Hurricane Wind Scale.

This forecast is updated monthly around the 15th each month until August. The next update will be issued around August 15. Note that these forecasts are to be taken as guides and not as gospel.

The Atlantic hurricane season officially began on June 1 and will conclude on November 30. Be prepared! Please share this blog, if you found it useful and follow me for more on the ongoing hurricane season, which, god forbid, could be another wild one like last year; also follow for all things weather and climate – TwitterFacebook and Instagram.





June Updated Forecast for the 2021 Atlantic Hurricane Season

19 06 2021

Dale C. S. Destin |

The numbers for this hurricane season are likely to be very high once again. My updated forecast for the 2021 season is out, and it continues to call for an above normal season being likely. The confidence of an above normal season has grown from 69 to 78%. It is also possible that the season could be super hyperactive with more than 19 named storms likely.

The prediction is still for 22 named storms (tropical storms and hurricanes), with a 70 percent confidence or high confidence of the number ranging between 17 to 28. It is also likely–56 percent chance (down 2), that the number of named storms will exceed 19 and be in the top 10 percentile of the historical record, dating back to 1851.

My forecast also calls for an accumulated cyclone energy (ACE) index of 186 (up 7) with a high confidence of the range being 112 to 286. There is also a 44 percent chance (up 9) of the ACE index exceeding 223. Also predicted are 9 hurricanes (down 1) with a 70 percent confidence of  the total being 6 to 13, and 5 major hurricanes (up 1) with high confidence of 2 to 7.

If this forecast pans out, this season would be the most active since 2017, in terms of ACE, and the 10th most active on record dating back to 1851. It would also be ranked third for the highest number of named storms and tied for 11th and 17th for the most hurricanes and major hurricanes respectively.

The main reasons for the above normal forecasts are the likely above normal sea surface temperatures across the tropical North Atlantic and a weak La Niño and or cold-neutral El Niño Southern Oscillation (ENSO) during August to October–the peak of the hurricane season.

A typical season, based on the standard climate period 1991-2020, has 14 named storms, 7 hurricanes and 3 major hurricanes. Major hurricanes have sustained wind speeds of at least 178 km/h or 111 miles per hour (e.g., Category 3 or higher), according to the Saffir Simpson Hurricane Wind Scale.

This forecast is updated monthly around the 15th each month until August. The next update will be issued around July 15.

The Atlantic hurricane season officially began on June 1 and will conclude on November 30. Be prepared! Please share this blog, if you found it useful and follow me for more on the ongoing hurricane season, which unfortunately could be another wild one, and for all things weather and climate – TwitterFacebook and Instagram.





Drought Worsens to Serious Levels

20 04 2021

Dale C. S. Destin |

With continued below normal rainfall through March, the meteorological drought has worsened to serious levels for Antigua. That is the “good” news, the bad news is that the drought is likely to get worse over the next few months, as below normal rainfall is forecast by most models.

WMO Lead Centre for Long-Range Forecast Multi-Model Ensemble is forecasting 60-70% likelihood of below normal rainfall for Antigua and Barbuda; only two of the 12 models forecast near normal rainfall. Also, below normal rainfall is likely for much of the Caribbean Basin.

This is the driest start to a year since 2015 and the ninth driest first-quarter for Antigua in a series that dates to 1928. The island-average rainfall of 93.0 mm (3.66 in) represents only 57 percent of the normal total for January to March (JFM); hence, 43 percent of the regular flow of water from our skies was missed by our plants, catchments, economy and ecosystems.

The rainfall for March of 29.2 mm (1.15 in) is the worst for the month since 2015. The total was only 63 percent of the usual amount for the first month of spring; hence, a significant deficit of 37 percent.

There is no discernible respite in the foreseeable future. The vast majority of models are forecasting deficit rainfall to be the order of the next six months. Thus, the drought is likely to get worse. Our catchments could again revert to mud patches and or grasslands, which has virtually become an annual phenomenon.

Other droughts generally lag a meteorological drought; however, it is evident from our catchments that agricultural, hydrological and ecological droughts, to some degree, are occurring or imminent. There is also the concern that this may precipitate a socio-economic drought. Our utilisation of the ocean around us for fresh water has made us resilient; notwithstanding, there are still likely to be notable impacts, direct and indirect, when the other droughts get underway in earnest.

The water authority, the Antigua Public Utilities Authority (APUA), has already signal an end to surface water to occur in a few months, that is even more likely than when it was said over a month ago, as rainfall for April has been virtually absent, thus far. Water rationing is imminent, if not already occurring.

Antigua is not alone in experiencing significant first-quarter rainfall deficits. Much of the Eastern Caribbean is having a similar thirst for rainfall. Short and long-term droughts continue to evolve across many places, and it is probable that the shortfall is precipitation will worsen and or spread to most of the Basin over the upcoming months.

Exert from the Caribbean Climate Outlook Forum (CariCOF) Drought Outlook for March 2021

Please continue to follow me for more on this evolving drought and all things weather and climate via TwitterFacebook and Instagram. Also, share this blog, if you found it useful. 





The Great 1843 Mother of All Caribbean Earthquakes

8 02 2021

Dale C. S. Destin |

At 10:37 am, February 8, 1843 – 178 years ago today, the mother of all Caribbean earthquakes struck the region. This is believed to be strongest of all Caribbean earthquakes, ever reported. Dubbed the “The great 1843 earthquake” by Beauducel and Feuillet of the Institut de Physique du Globe de Paris, it killed more than 1500 people and perhaps up to 6000, most in Guadeloupe, and caused catastrophic damage.  

Earthquake event of 8 February 1843, where black star, southeast of Antigua, indicates epicenter from Feuillard [1985]. Thick dashed lines, with roman numerals between, indicate approximate isoseists – equal earthquake intensity. Dashed areas show the approximate size of the ruptured zones estimated by using the Wells and Coppersmith [1994] relation between rupture length and magnitude. See Natalie Feuillet et al

The powerful earthquake, with an estimated magnitude of 8.5, struck the Caribbean, with epicentre between Antigua and Guadeloupe. Different sources have it centre in slightly different places, which is not unusual; however, all have it within 50 miles of the above-mentioned islands.

The monster quake is credited with the total destruction of the Guadeloupe city of  Pointe-à-Pitre. What the shaking did not demolish directly, fire sparked by it consumed the rest. Eyewitness accounts and newspaper reports painted a very dismal picture of the aftermath of this earth-shattering quake, which caused damage throughout most of the Eastern Caribbean. Here is an account of damage to Antigua, according to an 1843 report by Captain of the ship – Royal Mail Steam Packet Dee, as cited by José Grases G. 1990 and obtained from the The University of the West Indies Seismic Research Centre (UWI-SRC) website:

This island has suffered most severely, the whole of the churches and mills throughout the island being a heap of ruins. The organ in the Church of St. John’s totally destroyed; the Dockyard at  English Harbour is sunk considerably, many parts being under water, the whole of the  stone houses in a complete ruinous state, the walls partly or wholly down; the water tanks containing nearly 11,000 tons of water burst with an  awful crash; the earthquake lasted about 4 minutes. Mr. Hart, Clerk in charge of the Dockyard, English Harbour, states that 3 clocks in the  neighbourhood  stopped  at  10h:  40M:  a.m. Precise accounts had not  been received from the  interior. It is ascertained 40 lives had been lost – fears were entertained it was short of the actual loss. The Governor’s House (Dow’s  Hill) is partially destroyed with nearly all its furniture; the  Ridge Barracks much damaged; the Custom House, Court House, and Wesleyan Meeting House destroyed.”

No photo description available.
Damage from the 1974 Antigua earthquake. The 1843 earthquake was 10 times stronger. Photos by UWI-SRC

This earthquake, which ranks among the top 20 strongest ever in the world, was said to have been felt as far away as New York, USA. It was probably a megathrust earthquake – the most powerful kinds. It was up to 10 times stronger than the infamous 1974 Antigua earthquake and up to 32 times stronger than the 2010 Haiti earthquake.

It must be noted that there are conflicting estimates of the magnitude of this catastrophic event with, at least, one expert indicating that the magnitude was as low as 7.5 to 8. I am more persuaded  by the 8.5 magnitude estimate, since this appears to be the most recent finding – Natalie Feuillet et al., and also supported by, at least, two other experts. In some literature it is listed at magnitude 8.3. At any rate, it was not your garden variety earthquake by any stretch of the imagination.

According to the UWI-SRC, earthquakes are a daily reality across the Caribbean, especially the northeast Caribbean where hundreds occur annually, although most are not felt.

Over the years, the UWI-SRC has expressed concerned over the potential for an 1843 or 1974 caliber earthquake impacting the northeast Caribbean. Although earthquakes, especially large ones, are virtually unpredictable, the public should be prepared, as moderate to significant sized earthquakes may impact the region at any time. Individual, community and national measures should always be in place to mitigate the impacts of earthquakes.

For more on seismic activity in the Eastern Caribbean visit: UWI-SRC. Also please continue to follow me for all things weather and climate via TwitterFacebook and Instagram. Share this blog, if you found it useful.





November 2020 Hurricane Summary

9 12 2020

Dale C. S. Destin|

The hurricane season saved the worst for last. November, the last month of the official season, produced the strongest Atlantic hurricane for the year – Category 5 Hurricane Iota, with peak winds of 260 km/h (160 mph).

Category 5 Hurricane Iota making landfall on Nicaragua – 17 Nov 2020

Iota devastated Central America, particularly Honduras and Nicaragua, killing 61 and causing at least US$564 million in damage. However, long before Iota was Iota, her precursor – Tropical Disturbance AL98, was quite destructive to Antigua. It dumped over 373 mm (over 14 in) of rain in 24-hours across parts of mainly western Antigua. This Lenny-type-rainfall caused massive flooding, resulting in inevitable damage in the hundreds of millions of dollars.

Iota not only became the only Category 5 hurricane for the season, but also the first Category 5 hurricane to have its origin in November. The 1932 Cuba hurricane, also known as the Hurricane of Santa Cruz del Sur or the 1932 Camagüey hurricane, became a Category 5 hurricane in November but has its origin in October, unlike Iota.

Iota’s late rise to Category 5 status also keeps the undesirable record streak of seasons going, with at least one such maximum category hurricane. The streak is at five seasons, dating back to 2016.

Tropical Storm Theta was the other named tropical cyclone to have its origin in November. It had peak winds of 110 km/h (70 mph) and minimal impact to the Canary Islands and Madeira.

Eta had its origin in October but developed into a Category 4 hurricane in November and impacted Nicaragua, less than two weeks ahead of Iota. This November tied with November 2005, 2001, 1961 and 1931 for the most storms named in the month.

With the formation of Iota, we were nine deep into the Greek Alphabet – the back up list for naming storms. Notwithstanding, Antigua and Barbuda and the rest of the Eastern Caribbean remained hurricane-free right through the season and was happy to see the back of November.

The hurricane season officially ended November 30, with a record 30 named storms, 13 hurricanes and 6 major hurricanes. Only 2005 is close with 28 named storms, a record that most never thought would ever be broken.  

Recall that an average season produces 12 named storms, 6 hurricanes and 3 major hurricanes, Thus, this season produced 250 percent of the average number of named storms, 217 percent of the average number of hurricane and 200 percent of the average number of major hurricanes.

Please continue to follow me for more on the hurricane season and all things weather and climate via TwitterFacebook and Instagram. Also, share this blog, if you found it useful.





Record-breaking 2020 Atlantic Hurricane Season Ends

1 12 2020

Dale C. S. Destin|

Five tropical cyclones present in the Atlantic – September 14, 2020

The busiest Atlantic hurricane season ever ended last night. The season produced a record-breaking 30 named storms. It also produced 13 hurricanes, the second highest on record dating back to 1851. Further, there were six major hurricanes, Category 3 and over, which tied for the second highest on record. The record season took over 400 lives and caused over US$41 billion in damage.

Only once before a season exceeded 20 named storms – 2005 with 28 named storms, which is the record eclipsed by 2020. However, 2020 remains second to 2005 with respect to the number of hurricanes – 15, and the number of major hurricanes – 7. Six other seasons have a similar total of major hurricanes as 2020 – 2017, 2004, 1950 1996, 1933 and 1926. An average hurricane season has 12 named storms, 6 hurricanes and 3 major hurricanes.

Ranking of the 2020 hurricane season based on number of named storms, hurricanes, major hurricanes and ACE, compared to the records

Although the most eye-catching statistic for a given season is the number of storms, this is not the metric used to determine its overall activity. The Accumulated Cyclone Energy (ACE) index is the internationally accepted metric used to categorise the activity of a season. The ACE takes into consideration not only the number of named cyclones but also their strength and duration. Hence, based on the ACE, 2020 is the 13th most active hurricane season on record, with an ACE index of 180. The most active hurricane season on record remains 1933, with an ACE of 259, 44% more than 2020.

Based on NOAA’s classification, the 2020 season was extremely active or hyperactive. However, NOAA’s classification of season has its challenges, allowing for one season to simultaneously have two classifications. A better approach is to classify seasons strictly by the ACE index. This approach would make the 2020 season and above normal season but NOT well above normal or hyperactive, according to 268Weather’s classification. It fell short by seven ACE needed to take it to 187 – 268Weather’s current threshold for a hyperactive season.

268Weather’s seasonal hurricane forecasts accurately predicted a very high likelihood of an above-normal or active season. 268Weather is proud to be among the few to have gotten the forecast right from very early – April. 268Weather was the only entity to forecast over 28 names storms, up to 32 were predicted and 30 formed.

Animated satellite imagery of the named storms that occurred during the 2020 Atlantic Hurricane Season – May 13 through November 18. Credit: NOAA Satellites

It was a relentless hurricane season. It kept forecasters on their toes continuously. There was an average of 4-5 tropical storms per month since June with one forming about every week. Thankfully, we were not significantly impacted by any of the season’s two-and-half dozen named storms, over a dozen hurricanes and half dozen major hurricanes. Also, the Eastern Caribbean virtually got away “scot free” from significant impacts.

The 2020 season got off to an early start with Arthur on 16 May and Bertha 27 May. From May to July, there was a record nine storms. This is more storms than 80 of the previous 169 seasons, including 2014, 1997 and every season from 1991 to 1994. By September 18, the 21-name Atlantic list was exhausted when Tropical Storm Wilfred formed. Thus, the season “went Greek” i.e. the backup Greek List was turned to for names for the remainder of the season. To date, we are 9 names deep into the list with Iota being the last and the most powerful Atlantic hurricane for the year.

The Atlantic has done a 5-peat – produced five active/above normal seasons in a row. This is the longest such streak, on record. Further, it’s the most active hurricane season since 2017 and the second most active since 2005. Eighteen of the last 26 hurricane seasons, dating back to 1995, were above normal.

The reason for the large percentage of active hurricane seasons since 1995 is due to the positive or warm phase of the Atlantic Multidecadal Oscillation (AMO). Positive phases of the AMO are strongly linked to active eras of Atlantic hurricane seasons, which historically last for about 20 to 40 years.

Like other active years, this year’s activity is owed to an interrelated set of oceanic and atmospheric conditions linked to the warm AMO, such as warmer-than-usual North Atlantic sea surface temperatures (SSTs) and cooler-than-normal middle to eastern equatorial Pacific SSTs i.e. La Nina. These conditions which are also associated with weak wind shear caused the record-breaking, extremely active hurricane season.

Other notable records set by the 2020 season include the following:

  • Twenty-seven tropical storms broke the record for the earliest formation by number
  • A record 10 tropical cyclones rapidly intensified, tying 1995
  • This season is the record sixth consecutive year with pre-season named tropical cyclones
  • A record 10 tropical cyclones were named in September with 9 having their origin in the month, the most for any month
  • Iota became the only Category 5 hurricane to have its origin in November and the latest on record

For more details on the 2020 Atlantic hurricane season, our monthly summaries: May, June, July, August, September, October and November (coming soon).

This season has officially ended, but it is possible, although not probable, for additional storms to develop. Stay vigilant and make sure your family is prepared for all hazards, especially those related to weather and climate. The 2021 hurricane season will officially begin June 1 and 268Weather will issue monthly forecasts starting early April.





October Not Over 2020 Hurricane Summary

2 11 2020

Dale C. S. Destin|

The hurricane season was certainly not over in October. There was a record-tying number of major hurricanes – two, Delta and Epsilon; this represents over 665 percent of average (normal). The number of named storms – five, was 250 percent of average. Further, the number of hurricanes – four, was over 360 percent of average.

October Not Over 2020 Summary. Note, although Eta became a storm in November it is credited to October to which it owes its origin, according to the international standard

October 2020 is only the fifth October on record with two major hurricanes. The last time there were two major hurricanes in October was 2005. The month averages a major hurricane once every three to four years. Previous years with two major hurricanes are 2005, 2001, 1950 and 1894.

It was a very active October. The metric that speaks more completely to the activity of a month or a hurricane season is called the accumulated cyclone energy (ACE) index. Normally, the month produces an ACE index of 14.5 – that was more than doubled for this October – 39.2. Compared with the activity for September, although it was a record-setting month regarding named storms, the ACE index of 63 was only 1.23 the average – 51.4. Hence, October was more active relative to itself than September was.

Using the ACE index metric, this October was more active that 28 previous full hurricane seasons of 169, including the 2013 season, which had 14 named storms but an ACE of 36. Also, the two major hurricanes during the month were more than or equal to 125 full seasons. We would have also seen more or the same number of hurricanes than 71 full seasons, including 2015.

Every named storm in October was earlier than those with the same names that formed during October of the 2005 hurricane season, which is the only other season with more than 20 named storms, on record. The records were broken by as many as 41 days. This may be an omen for this season setting a record for the highest number of named storms.

Thankfully, none of these storms threatened Antigua and Barbuda and the rest of the Eastern Caribbean. The most we got were moderate to large swells from Epsilon along with minimal showers from a few very weak feeder bands. The rest of the Caribbean Islands fared well also with none experiencing storm or hurricane conditions. Delta was a relatively close call for Jamaica, the Cayman Islands and Cuba.

We are through the season, except for one more month, officially – November. Thus far, there have been 28 named storms – the most through October and tied with 2005 for the most on record, for a season. The 2005 record is now expected to be broken. There have also been 11 hurricanes of which 4 were major hurricanes – Category 3 or over.

2020 Atlantic hurricane season summary map.png

Recall that an average season produces 12 named storms, 6 hurricanes and 3 major hurricanes. Thus, this season has produced, thus far, 233 percent of average number of named storms, 183 percent of average number of hurricanes and 133 percent average number of major hurricanes.

Notwithstanding the record number of named storms, the season is very far from being a record active one. Recall that the activity of a season is based on the ACE index. The ACE index, thus far for 2020, is 143.9; this is only 136 percent of the average – 105.5.

This season is not even ranked in the top 20 with respect to ACE. It is currently at 27th and is unlikely to reach the top 10. The ACE index for a season is also a measure of the potential destructiveness of the collective named storms. This means that although 2020 has produced a record number of storms, there are several seasons that were potentially more destructive, including the 2017 season with and ACE index of 223.

Top 20 Most Active Atlantic Hurricane Season. TS – Tropical Storms; HU – Hurricanes; MH – Major Hurricanes. Credit Wikipedia.

The most active season on record, using the ACE index metric, remains 1933, with an index of 259, produced by “just” 20 named storms. This is nine more ACE than the 2005 season, which had eight (40 percent) more named storms.  

Delta – 5 to 11 October, became the record-tying fourth named storm of 2020 to strike Louisiana, as well as the record-breaking 10th named storm to strike the United States. It was a very destructive Category 4 hurricane with 1-minute peak sustained winds of 230 km/h (145 mph). It caused, at least, US$2 billion in damage and killed 6 people. It also affected Jamaica, the Cayman Islands, The Yucatán Peninsula, the Gulf Coast, Southeastern and Northeastern United States.  

Hurricane Delta, Across the Western Caribbean Sea – Oct 6, 2020

Epsilon – 19 to 26 October, impacted Bermuda minimally, passing about 190 to its east. It had peak sustained winds of 185 km/h (115 mph), making it a Category 3 hurricane. Exact damage to date is unknown but it generated moderate to large swells across most Atlantic coastlines of the Caribbean, the Bahamas, the United States and Canada.

Hurricane Epsilon, Passing Northeast of Bermuda, Oct 23, 2020

Zeta – 24 to 30 October, became the record-tying sixth hurricane to make landfall on the United states in one year. It was also the record fifth named storm to make landfall on Louisiana in one year. Zeta had peak 1-minute sustained winds of 175 km/h (110 mph) and caused eight fatalities and over US$13.7 million in damage across Jamaica alone. It also impacted the Cayman Islands, Central America, the Yucatán Peninsula and the Mid-Atlantic United States.  

Hurricane Zeta Across the Western Caribbean Sea – Oct 26, 2020

Eta – 31 October to present, became the record-tying 28th named storm for the year, placing 2020 level with 2005 for highest number of named storms. Eta is currently a Category 1 hurricane with the potential to reach Category 3 intensity. It is an extreme threat to Nicaragua and Honduras with the potential to cause Catastrophic damage.

Hurricane Eta Across the Western Caribbean Seas – Nov 2, 2020

The month also produced Tropical Storm Gamma – 2 to 6 October. Gamma made landfall on the Yucatán Peninsula with peak 1-minute sustained winds of 110 km/h (70 mph), killing 7 with the damage amount presently unknown.  

Please continue to follow me for more on the hurricane season and all things weather and climate via TwitterFacebook and Instagram. Also, share this blog, if you found it useful.





The Hurricane Season in October Not Over

9 10 2020

Dale C. S. Destin|

According to the old mariner’s poem, which attempts to describe the hurricane season, it says October all over, suggesting that the Hurricane season ends by the time October comes around. However, this may be a rhyme of convenience or perhaps the author and the publisher of the famous poem are from a place that never saw tropical cyclones in October, as the hurricane season in no way, shape or form ends in October. October – not over!

Already the month has produced two named storms – Gamma and Delta, with Delta currently a Category 3 hurricane over the Gulf of Mexico, threatening the Gulf Coast States of the US.

Major Hurricane Delta – October 9, 2020

Tropical storms, including hurricanes, are no strangers to the Caribbean in October. Here in Antigua and Barbuda, we have been affected by at least 16 named storms since 1851 – 5 were hurricanes, 2 of which were major hurricanes. Our last hurricane was Gonzalo of 2014, which rapidly intensified just east of us and caught many persons off guard. Damage to Antigua and Barbuda amounted to about US$40 million.

Gonzalo also impacted the rest of the Leeward Islands, Puerto Rico, Bermuda, Newfoundland, the United Kingdom and Europe. In the end the fatalities amounted to six and damage was over US$317 million.

Hurricane Gonzalo over the Leeward Islands – Oct 13, 2014

The Atlantic Basin, including the Caribbean, in October, averages around two named storms, including one hurricane and a major hurricane – Category 3 or higher, every three to four years, based on the current climatological period of 1981-2010. These numbers have already been tied, with well over half of the month remaining.

Category 5 hurricanes are relatively rare for October but not unheard of. On average, the month sees a Category 5 hurricane every 10 to 11 years. The last Category 5 October hurricane was Michael of 2018.

Category 5 Hurricane Michael – Oct 10, 2018

The probability of Antigua and Barbuda being impacted by a storm or hurricane, in October, is around 10 percent, based on the 1981-2010 base period. This means that we are affected by a storm or hurricane, in October, every 10 years. The probability of, at least, one hurricane impacting us is the same. With our last October hurricane being Omar of 2014, statistically, we are not due for an October hurricane until 2024. The probability of a major hurricane is 3 percent – one every 33 years, on average.

Since 1851, the Eastern Caribbean has been impacted by around 28 named storms of which 13 were hurricanes and one major hurricane, according to coast.noaa.gov/hurricanes. Over the base period of 1981-2010, there have been around 8 named storms, 4 of which were hurricanes and 1 was a major hurricane. This translates to the Eastern Caribbean having a 23 percent chance of a named storm, 12 percent chance of a hurricane and 3 percent chance of a major hurricane in October. This means that a named storm impacts the Eastern Caribbean, in October, every 4-5 years, a hurricane every 8-9 years and a major hurricane every 33 years, on average.

The probability of a storm or hurricane (named storm or named tropical cyclone) across the western Caribbean, in October, is around 45 percent. Surprisingly, this is greater than the probability – 37 percent, for a named storm, in September, for the same area. Meanwhile, for the central Caribbean for October, this probability is around 26 percent.

October Hurricane Climatology
The zones of origin and tracks of named tropical cyclones (tropical storms and hurricanes) in October during the hurricane season

The last October hurricane to impact the Caribbean was Michael of 2018 – it impacted Cuba as a Category 2 hurricane and then when on to become a Category 5 hurricane just before making landfall on Florida Panhandle. Michael also impacted Central America, causing deaths across Honduras, Nicaragua and El Salvador. All toll, it caused 43 fatalities and over US$25 billion in damage.

From 1851 to 2019, October has produced a total of 348 named storms of which 207 hurricanes and 46 major hurricanes. For the climate period 1981-2010, there have been 61 named storms with 33 being hurricanes and 9 being major hurricanes.

Click for large image
Click for larger image
Click for larger image

It must be noted that there are likely named tropical cyclones (tropical storms and hurricanes) that were missed prior to the satellite era – before the mid-1960s.

October 1950 holds the record for the most named storms for the month – eight. Meanwhile, October 1870 is the record holder for the most hurricanes for the month – six. Further, October has frice produced a maximum of two major hurricanes – 2005, 2001, 1950 and 1894.

What will this October-not-over bring? Thus far, it has already tied the average numbers for the month. Given that each month of the hurricane season has produced, at least, 1.5 times its average number of named storms and that up to 32 named storms are forecast for the year, with 25 gone, this October could end up producing another five storms of which all could become hurricanes and four reaching Category 3 or higher intensity.  

Now you can see why it should be called October not over, as opposed to October all over. Only about 20 times in 169 years there has been no storms in October and only twice for this millennium, thus far.

Please continue to follow me for more on the hurricane season and all things weather and climate via TwitterFacebook and Instagram. Also, share this blog, if you found it useful. Stay prepared!





September Remember 2020 Hurricane Summary

4 10 2020

Dale C. S. Destin|

It was a wild, record-setting September to remember. There was a record nine named storms that formed in the month, breaking the previous record of eight which occurred 2010, 2002 and 1949. Of the nine named storms, four became hurricanes, and one reached major hurricane status – Category 4 Teddy. Juxtapose that with the normal for the month of four named storms, two to three hurricanes and one major hurricane.

This September was so wild, that we exhausted the primary list of names designated to the season, with two more months to go. Thus, the backup list is now in use only for the second time on record. So, the season has gone Greek i.e. storms are now being given names based on the Greek Alphabet. The only other time the season went Greek was 2005 and it did so over a month later than this season – October 22, when Beta of that season formed.

The exhausted primary list of names for named storms for 2020
The backup list for storms when there are more than 21 named storms/tropical cyclones

The frantic month has produced as much as or more named storms than 92 full seasons on record dating back to 1851. This is easily and remarkably more than half – 54 percent, of the 169 seasons on record. This includes 2014, 2009 and 1997, which had nine or less named storms.

Every named storm in September was the earliest storm to develop in the Atlantic for their respective letter or number, on record. The records were broken by as many as 34 days.

Interestingly, none of these storms threatened Antigua and Barbuda and the rest of the Eastern Caribbean. The most we got were large swells from Teddy along with some decent downpours from a few of its feeder bands.

Feeder bands from Teddy impacting the northeast Caribbean to include Antigua and Barbuda – Sep 20, 2020
Feeder band from Teddy across Barbuda, Antigua, Guadeloupe and Dominica – Sep 19, 2020

We are through two-thirds of the season, with two more months to go, officially, and we have already seen 23 named stormsthe most through September and the second most on record, for a season. Only 2005 saw more named storms – 28, and this record is in jeopardy, given the trend and my forecast. There have also been eight hurricanes of which two were major hurricanes – Category 3 or over.

Recall that an average season produces 12 named storms, 6 hurricanes and 3 major hurricanes. Thus, this season has produced, thus far, 191 percent of average number of named storms and 133 percent of average number of hurricanes. Thankfully, you may say, major hurricanes are lagging behind.

A season through September normally produces 9 named storms, 5 hurricanes and 2 major hurricanes. Thus, this season through September has produced 256 percent of average number of named storms, 160 percent of average number of hurricanes and 100 percent of average number of major hurricanes.

 

2020 tropical cyclone (tropical depression, tropical storm and hurricane) tracks through September 2020

 Teddy – 12 to 27 September, became the second major hurricane for the season, with peak winds of 220 km/h (140 mph). It impacted Bermuda with minimal storm-force winds and slammed into eastern Canada with Category 1 winds, but as an extra-tropical cyclone. It also impacted the northern Caribbean and the East Coast of the United States with high swells and surfs. The system was responsible for three fatalities.

Teddy southeast of Bermuda – Sep 20, 2020

Sally – 11 to 18 September, became the first hurricane to make landfall on Alabama since Ivan of 2004. It was a very destructive Category 2 cyclone with peak sustained winds of 165 km/h (105 mph). It caused, at least, US$8 billion in damage and killed 8 people. It also affected the Bahamas and Cuba.  

Sally impacting much of the Gulf Coast of the United States – Sep 15, 2020

Paulette – 7 to 16, 22 to 30 September, became the first hurricane to make landfall on Bermuda since “our” Gonzalo of 2014. It had peak sustained winds of 165 km/h (105 mph). Damage to date is unknown but it killed one person. It also impacted the Cape Verde Islands, the East Coast of the United States, Azores and Madeira with mainly swells and surfs. Note that the system died on 22 September and was resurrected September before dying for good 30 September.

Paulette heading for Bermuda – Sep 13, 2020

Nana – 1 to 4 September, made landfall on Belize as a Category 1 hurricane – 120 km/h (75 mph) before moving on to Guatemala but only caused minor damage. Damage is estimated to be, at least, US$10.2 million and there were no deaths.

Nana impacting Belize and other nearby Central American countries – Sep 3, 2020

There were five other named storms that did not reach hurricane status – Rene, Vicky, Wilfred, Alpha and Beta. Beta was the strongest of them with peak sustained winds of 95 km/h (60 mph). Collectively, damage from them were minor; however, they killed three people.

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Busy Week Ahead for the Caribbean

16 08 2020

Dale C. S. Destin |

Looks like the Caribbean is set for another busy week. There is the potential for two tropical cyclones – tropical depressions, tropical storms or hurricanes, impacting the area.

Tropical Disturbances AL97 (near the Caribbean) and AL96 (near Africa)

It is the start of a new week but the continuation of a record-breaking hurricane season, which could add two more storms to its tally, in days. There are two new disturbances between Africa and the Caribbean, taking aim at the islands.

Satellite picture animation showing the locations of the distrubances

It is uncertain as to whether these disturbances will become tropical cyclones, where they will go and what hazards, they will bring to the area. However, at this time of the year, most disturbances do develop into tropical cyclones, as conditions are generally conducive, like they are currently, bar the dry and dusty Saharan air.

Today, we saw the end of Tropical Storm Josephine, which threatened the area but eventually passed a safe distance north of all the islands.

Tropical Storm Josephine passing by on Saturday afternoon, 15 August, 2020

With Josephine gone, all attention is now on Disturbances AL96 and AL97. They both have a 50 percent chance of formation. And they both have tracks that take them through the Caribbean.

The second of the two systems, AL96, appears to be more of a future threat to the Caribbean, particularly the Leeward Islands. AL97 is perhaps moving too rapidly for much development to take place before reaching the Eastern Caribbean tomorrow; however, it is forecast to slow down in the Caribbean Sea where it will encounter favourable conditions for formation Wednesday.

Most available models have AL97 becoming a tropical storm in 48 hours – Tuesday night/Wednesday
Most available models have AL97 going through the southern Caribbean, at most, as a Tropical Depression

The gold standard of models – the ECMWF IFS or European model is very sweet on AL96. It gives it a relatively high chance of becoming a tropical storm and track towards our “neck of the woods” – the Leeward Islands this upcoming weekend. This week could end similarly to the one just gone – with us under a Tropical Cyclone Alert or worse.

Already for the season, there have been 11 named storms, the most to have ever occurred this early in the year, with the more active half of the hurricane season just getting started. With half of the season to go, only 48 out a total of 169 seasons, dating back to 1851, has seen more storms.

Be prepared! Based on the forecast, the season is likely to produce, at least, nine more named storms, five more hurricanes and three major hurricanes. It is likely to be a very long season.

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