July Updated Forecast for the 2022 Atlantic Hurricane Season

20 07 2022

Dale C. S. Destin |

My July updated forecast for the 2022 Atlantic Hurricane Season is out, and it continues to call for a very busy and active season with the possibility of being super hyperactive. As of July 20, the forecast is for 19 named storms, 11 hurricanes and 5 major hurricanes. This includes Tropical Storms Alex Bonnie and Colin.

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 193, 41 above the threshold for an active season, based on 1991-2020 data.

A super hyperactive season like 2017 also remains possible. There is a 41 percent chance of the ACE exceeding 223. Further, there is a 50 percent chance of more than 19 named storms; 43 percent chance of more than 11 hurricanes and also a 35 percent chance of more than 6 major hurricanes.

If the forecast pans out, this season would be the most active season since 2017 and the ninth most active, on record, in terms of ACE, dating back to 1851.  

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.

For a more detailed forecast click here.

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





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.

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





August Updated Forecast for the 2021 Atlantic Hurricane Season

19 08 2021

Dale C. S. Destin |

The forecast for the 2021 hurricane Season continues to call for an active season with the possibility of it being super-hyperactive. The confidence of an above normal season has remained virtually unchanged at 78%. 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 or current climate period.

The prediction is now for 22 named storms (subtropical 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–69 percent chance, that the number of named storms will exceed 19 and be in the top 10 percentile of the current climate period.

My forecast also calls for an accumulated cyclone energy (ACE) index of 188 with a high confidence of the range being 115 to 284. Also predicted are 11 hurricanes with a 70 percent confidence of  the total being 7 to 15, and 5 major hurricanes with high confidence of 3 to 7.

The season could also be well above normal or super hyperactive. There is also a 45% chance of the ACE exceeding 223, the top 10 percentile of the current climate period. Further, there is a massive 69% chance of more than 19 named storms or the number of named storms reaching the top 10 percentile. There is also a 41% chance of more than 11 hurricanes and 45% 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, tied for 5th for the most hurricanes and 11th for the most major hurricanes.

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.

The season initially got off to a “flyer” but became sedate in July. Since the start of August, activity has picked back up, going at a rate of of about one-and-half times the normal season. To date, there have been eight named storms with three becoming hurricanes. A typical season, based on the standard climate period 1991-2020, has 14 named storms, 7 hurricanes and 3 major hurricanes.

The main reason for the above normal forecast is the likely weak La Niña conditions or cold El Niño Southern Oscillation (ENSO) during August to October–the peak of the hurricane season.

Please share this blog, if you found it useful and follow me for more on the ongoing hurricane season, which, god forbid, could end up to be another wild one like last year; also follow for all things weather and climate – TwitterFacebook and Instagram.





The Hurricane Season in November

9 11 2020

Dale C. S. Destin|

November hurricanes are almost unheard of for Antigua and Barbuda. I say almost because we have an exception – Hurricane Lenny of 1999. In 169 years of record dating back to 1851, Lenny is our (Antigua and Barbuda and the rest of the Eastern Caribbean) only November hurricane.

This image has an empty alt attribute; its file name is image-9.png
Lenny south of the US Virgin Islands. Credit Wikipedia
The Track of Hurricane Lenny – November 13-23, 1999

Prior to Lenny, we in the Eastern Caribbean, have not had a November named storm (tropical storm or hurricane) since 1896 – over 100 years before Lenny. November named storms amount to eight for the Eastern Caribbean, four of which affect Antigua, with Lenny being the only hurricane on record.

Lenny impacted Puerto Rico, the Virgin Islands, the Leeward Islands, the Windward Islands and even as far away as Colombia. It killed at least 17 people and caused over US$785 million in damage, a lot due to flooding.

The Atlantic Basin, including the Caribbean, averages one November named storm per year, one hurricane every other year and a major hurricane – Category 3 or higher intensity, every 10 years; this is based on the current climatological period of 1981-2010.

To date, no Category 5 hurricane has had its origin in November, based on the record. There was an unnamed Category 5 hurricane in 1932 that formed in October but reach Category 5 status in November; however, storms are credited to the month in which they were formed or originate in.

The probability of Antigua and Barbuda being impacted by a storm or hurricane, in November, is around 3 percent, based on the 1981-2010 base period. This translates to, at least, a storm or hurricane every 33 years, on average. With Lenny being our last hurricane, we are not due another hurricane in November until around the year 2032. The same is true for a major hurricane, in November.

The probability of a storm or hurricane impacting the Eastern Caribbean, in November, is around 6 percent or one every 16-17 years. This increases to around 12 percent or one every 8-9 years for the Central Caribbean and 28 percent or every 3-4 years for the Western Caribbean.

November Hurricane Climatology
The zones of origin and tracks of named tropical cyclones (tropical storms and hurricanes) in November.

The last November hurricane for the Caribbean was Otto of 2016. It formed across the southwest Caribbean Sea and impacted Nicaragua and Costa Rica, then crossed over into the Pacific Ocean. It killed 23 people and caused damage amounting to over US$192 million. It is the last Atlantic tropical cyclone to crossover to the Pacific and only the 14th to have done so.

Infrared satellite loop of Hurricane Otto making landfall as a Category 3 hurricane in Nicaragua on November 24. Credit Wikipedia.

From 1851 to 2019, November has produced a total of 92 named storms of which 56 were hurricanes and 6 were major hurricanes. For the climate period 1981-2010, there have been 20 named storms, 14 hurricane and 3 major hurricanes.

 November 1-10 Tropical Cyclone Genesis Climatology
Click for large image
 November 11-20 Tropical Cyclone Genesis Climatology
Click for large image
 November 21-30 Tropical Cyclone Genesis Climatology
Click for large image

It must always 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.

November 2005, 1961 and 1931 holds the record for the most named storms for the month – three. Further, 2001, 1994 and 1980 holds the record for the month for hurricanes – two. Meanwhile, no November on record has had more than one major hurricane in a year and only six have had a major hurricane – 2016, 2008, 1999, 1985, 1934 and 1912.

What will this November bring? Given that each month of this hurricane season has produced, 1.5 to 2.5 times its average number of named storms and that up to 32 named storms are forecast to the year, with 28 gone, this November could end up producing up to two storms, with one becoming a hurricane.

It is not over yet, but the end is nigh – November 30. Usually, November is a low stress month for hurricanes; however, this is 2020 – stay prepared!

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.

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.





Updated Hurricane Season Forecast – July Stand By 2020

13 07 2020

Dale C. S. Destin|

My “July stand by” updated forecast for the 2020 Atlantic Hurricane Season is out, and it continues to call for an above normal season, which is likely to be hyperactive – well above normal.

My forecast calls for 23 named storms (up 2), including Arthur, Bertha, Cristobal and Dolly, with 9 becoming hurricanes (unchanged) and 5 becoming major hurricanes (unchanged). The accumulated cyclone energy (ACE) index is forecast to be 200 (down 2). Further, there is a 70% confidence of

  • 17 to 28 named storms;
  • 6 to 13 becoming hurricanes;
  • 3 to 7 becoming major hurricanes and
  • 122 to 283 ACE.

If the forecast materialises, the ACE would be top 10 of all times. And if we use the ACE as an indicator of destructive potential, as some do, it means that the season’s destructive potential would also be top 10 of all times.

To date, the season has produced an ACE of 7.8, twice the usual amount for January through July 13. A normal season produces 106 ACE. Also, there have been six named storms to date, five time the average of 1.2. So, it has been a record busy season. Never before in history have we seen this many Atlantic tropical storms this early in the year.

The main reasons for the above normal forecast are:

  1. the continuation of a warmer than usual tropical North Atlantic (TNA) and
  2. a developing La Niña.

The greater the likelihood of these two things happening at the same time – August to October, the greater the chances for an above normal season.

There is one thing that may mitigate these developing near perfect conditions for tropical cyclone formation – more than usual Saharan Dust, streaming across the area. If this were to continue, the forecast numbers would be lower. Unfortunately, we have no skill in forecasting the dust beyond a week; hence, we do not know if the dust will continue beyond July and into the peak of the season – August to October.

Compared to my forecast, most other forecasts continue to call for an above normal season. However, compared with most other forecasts, my forecast is calling for a much more active season – 32% more, on average.

Accumulated Cyclone Energy (ACE) based on 15 forecasting entities, including 268Weather.

Clearly, we have no control over the numbers for the season. But notwithstanding the forecast, you should always prepare the same each season, as it only takes one hurricane to ruin your year and or life.

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





The Hurricane Season in July Stand By

5 07 2020

Dale C. S. Destin |

Updated July 7, 2022

Unlike June, we have been impacted by tropical cyclones – tropical depressions, tropical storms or hurricanes, in July. Hence, as the 1898 poem by R. Inwards said “stand by” for news of storms that may be coming our way. Notwithstanding, July is still a relatively slow month for tropical cyclone activity.

The last hurricane to impact Antigua and Barbuda, in July, was Hurricane Bertha of 1996. Bertha hit while we were still recovering from one of our busiest hurricane seasons in modern times – 1995, the year of Hurricanes Luis (Category 4) and Marilyn and Tropical Storm Iris.  

134 named storms for July with Hurricane Bertha of 1996 highlighted

The centre of Bertha passed just south of Barbuda, likely causing the island to experience all its 137 km/h (85 mph) winds it was packing, at the time. Passing north of Antigua, the system caused peak sustained winds of only 63 km/h (39 mph). Damage to Antigua was minimal but unclear for Barbuda. Regardless of the damage, the psychological trauma would have been extreme for many, coming 10 months after the horror of Luis.

Bertha also caused damage across the rest of the Leeward Islands, the Virgin Islands, Puerto Rico, the East Coast of the United States and Canada. The system caused a total of 12 fatalities and at least US$330 million in damage.

Category 3 Hurricane Bertha – July 9, 1996

The probability of us (Antigua and Barbuda) being impacted by a named storm – a tropical storm or hurricane, in July is around 3 percent. This means that we are impacted by a named storm every 33 years, on average; hence, we are not due for a named storm, in July, for another seven years.

Surprisingly, we have never been affect by a tropical cyclone in July when there was and La Niña, as there is now. The same is true when there is an El Niño; it is Neutral ENSOs that bring us tropical cyclones in July.

The probability of us being impacted by a hurricane is the same as indicated above for named storms. In our history, there have been six named storms of which one was a hurricane – Bertha.

July is also a relatively slow month for tropical cyclone activity across the Eastern Caribbean. The region has seen 25 named storms, 7 of which were hurricanes and 1 major hurricane – Category 3 Hurricane Emily of 2005, the strongest to pass through the islands in July.

Satellite image of Category 5 Hurricane Emily south of Jamaica – 16 July, 2005
The track of Category 5 Hurricane Emily – July, 2005
Storms to have pass through the Eastern Caribbean – 1851 to 2021

Elsa of 2021 is the last hurricane to impact the Caribbean in July and the strongest since Emily. It’s centre passed just south of Barbados and then just north of St. Vincent, significantly impacting those islands. It then travelled west-northwest across the Caribbean Sea, impacting Hispaniola, Jamaica and Cuba, as a tropical storm.

Elsa became the first tropical cyclone to cause sustained hurricane-force winds to impact Barbados since Janet of 1955. The system caused a total of 13 deaths and at least US$1.2 billion dollars in damage. One persons was killed in Martinique, two in the Dominican Republic, ten in the United States. In Barbados, more than 1,300 homes were damaged, including 62 homes which were completely destroyed. 

Elsa going from Tropical Storm to a Category 1 Hurricane and impacting Barbados and the Windward Islands on 2 July 2021

The probability of a hurricane impacting the Eastern Caribbean annually, in July, is around 6%. This means that the region gets a hurricane every 16 years, on average. With the last hurricane occurring last year, we are not due for another hurricane in July for another 15 years. The probability of a hurricane in July, across the central and western Caribbean is a little higher – 10%.

Overall, July averages one named storm per year, a hurricane every other year and a major hurricane every 6 to 7 years. The last major hurricane was Bertha of 2008 and the last Category 5 hurricane was Emily of 2005.

Based on record since 1851, July has produced 134 named storms of which 62 became hurricanes and 12 became major hurricanes. We note that there are likely storms that were missed prior to the Satellite era – prior to the mid-1960s. For the current standard climate period – 1981 to 2010, there have been 33 named storms, with 16 becoming hurricanes and 5 becoming major hurricanes.

July has had a maximum of 5 named storms in a given year – 2005. On two occasions, there have been 3 hurricanes – 1966 and 1916. Further, on two occasions there were two major hurricanes – 2005 and 1926.

The strongest hurricane on record – Hurricane Allen of 1980, formed on July 31. It slammed Martinique, St Lucia and St Vincent on August 3 with Category 4 winds. It then reached Category 5 in the Eastern Caribbean Sea before pummelling parts of the Dominica Republic, Haiti, Jamaica and Cuba, on August 6. Allen then reach maximum strength of 306 km/h (190 mph) near the western tip of Cuba, on August 7. Earlier on that day, it severely impacted parts of the Cayman Islands.

Category 5 Hurricane Allen of 1980 – the strongest Atlantic hurricane on record

It goes without saying that Allen left a long trail of death and or damage and destruction from Eastern Caribbean to the United States. Some damage was catastrophic, for example, St Lucia had 6 fatalities and over US$230 million in damage. Deaths from Allen totalled 269 and damage over US$1.5 billion.

Unlike May and June, above normal tropical cyclone activity in July normally signals a busy hurricane season. What will this July bring? We can’t be sure, but the forecast is for an above normal season. Whatever it brings, let’s be prepared! Be hurricane strong!

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





June Too Soon 2020 Hurricane Summary

1 07 2020

Dale C. S. Destin|

June too soon is over, one month down and five more to go for the Atlantic hurricane season. This June had two named storms – Tropical Storms Cristobal and Dolly, the most since 2017. Only four seasons have seen more named storms in June – 1968, 1936, 1909 and 1886.

2020 Tropical Cyclone Tracks Through June 30

Tropical Storm Cristobal became the third named storm for the year – June 1 to 10. It also became the earliest third named storm on record – previous was Tropical Storm Collin of 2016.

Clouds from Tropical Storm Cristobal covering much of Mexico and Central America

Interestingly, Cristobal formed from the remnants of Tropical Storm Amanda. Amanda was the first named storm of the East Pacific hurricane season. It formed on May 30, just south of Guatemala and west El Salvador and moved onshore that area May 31, then rapidly dissipated the same day. That was the end of Amanda but the start of Cristobal.

Together, Tropical Storms Amanda and Cristobal, left a trail of destruction and death caused mainly by torrential rainfall, amounting to up to 1016 mm (40 in), in some areas. The trail runs from Central America to Canada, passing through eastern Mexico, central United States and Canada.

Dolly – June 22 to 24, was a “sheep of a storm”. It formed over the Atlantic, hundreds of miles east of New York and travelled parallel to the east coasts of the United States and Canada, never making landfall.

Upon formation, Dolly became the third earliest fourth named storm in a year, on record. Only Tropical Storm Debby of 2012 and Tropical Storm Danielle of 2016, were earlier. Dolly also became the farthest north forming Atlantic tropical storm, on record, before July 1.

Four down, 13 to 22 more are forecast

Recall that there is a storm in June every other year; one hurricane every 8 years and a major hurricane every 50 years, on average. The month has now gone six years without a hurricane and 54 years without a major hurricane. A good “drought” to have, right?

Recall also the we (Antigua and Barbuda) has never had a storm in June, so the happy streak continues. This is also true for most islands of the Caribbean east of Cuba.

The season is certainly off to a busy record tying start. Thus far, there have been four named storms – Tropical Storms Arthur, Bertha, Cristobal and Dolly. This year ties with 2012 and 1954 for the most named storms by July 1.

Although it was an active June, it may have been more active, if not for record levels of Saharan Dust traversing the tropical North Atlantic, the Caribbean and especially the Western Caribbean and the Gulf of Mexico, the main development regions during June. It was certainly a dust event for the ages.  

Saharan Dust as seen by Goes 16 Satellite at mid day June 23, 2020

So, it’s 30 days down and 152 more to go for the 2020 Atlantic hurricane season. Attention now turns to July stand by. Be prepared, be hurricane strong!

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.





Tropical Storms in May Mean Nothing

15 05 2020

Dale C. S. Destin |

The first tropical or subtropical storm for the pre-hurricane season is about to form in the Bahamas. Some think that this is a harbinger (sign) for the upcoming hurricane season – June 1 to November 30, but is it?

Tropical disturbance AL90 across the Bahamas with an 80% chance of becoming Tropical Storm Arthur within 48 hours.

To the “naked eyes”, it is understood why some may take a storm forming in May as a sign of bad news for the upcoming hurricane season; however, the numbers don’t agree.

The numbers say that it usually means nothing in terms of the overall activity of the upcoming season. According to NOAA, there have been 29 named storms in May, spread over 27 seasons from 1842 to 2019. Of the 27 seasons, using NOAA’s definitions, nine were above normal (active or hyperactive), 11 were near normal and 7 were below normal (inactive or quiet).

Overall, most seasons with a storm in May, are near normal – 11 times of 27 – 41%. However, from a statistical standpoint, there are no significant differences between above, near or below normal seasons, when there is a storm in May. Hence, a tropical storm forming in the month has no bearing on the activity of the upcoming hurricane season.

Of the 27 seasons with May storms, 9 or 33% was active or above normal; 11 or 41% was normal and 7 or 26% was quiet or inactive

Notwithstanding the above, this hurricane season is expected to be above normal or likely hyperactive – well above normal, see my latest forecast. Clearly, this has nothing to do with the expected formation of Tropical Storm Arthur over the Bahamas.

Further on the tropical cyclone climatology on May, of the 29 named storms to have formed in the month, 5 became hurricanes with none ever becoming a major hurricane. The strongest tropical cyclone of the month occurred in 1863 – a Category 2 unnamed cyclone.

The only Cat 2 May Hurricane on record – Unnamed Hurricane – 1863

On average, there is one storm forming in May every 7-8 years. However, there have been a storm in May of the last 2 years and 6 in the last 10 years. Twice, two storms formed in May of the same season – 2012 and 1887, the most of any. So much for averages, right!

The Eastern Caribbean has never been impacted by a tropical cyclone in May, “knock wood”, based on available record dating back to 1842.

Storms forming in this part of the region in May are not unusual. Of the 29 May storms, 28% have formed or traverse within 300 miles of Nassau, Bahamas.

Unfortunately for the Bahamas, this year they are still recovering from Super Category 5 Hurricane Dorian of September 2019, which levelled much of Northwest Bahamas. You may say that they can’t “catch a break”, as they are about to deal with potentially strong storm-force winds and flooding rainfall, in addition to dealing with the COVID-19 Pandemic.

Possible tracks of what is expected to become Tropical Storm Arthur in 48 hours

May storms mean nothing in terms of the overall activity of the hurricane season; however, they mean a lot with respect to where they impact. Let us be prepared regardless of omens or forecasts for the season – it only takes one hurricane to ruin your year or life.

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





The 2019 Atlantic Hurricane Season Summary

30 11 2019

Dale C.S. Destin|

The 2019 Atlantic hurricane season will come to an end midnight tonight. It will long be remembered for Super Category 5 Hurricane Dorian’s destruction of the northwest Bahamas. The season was also an above normal (or active) one, consistent with my initial forecast issued in April and the updates issued May, June, July and August.

2019 Atlantic basin tropical cyclone tracks.

The active year produced 18 named storms, 6 hurricanes, 3 major hurricanes and over 130 Accumulated Cyclone Energy (ACE). Overall, this year ranks 35 out of 169 on record, dating back to 1851, based on the ACE – the internationally accepted metric for determining the activity of hurricane seasons.

Quite interestingly and unprecedentedly, seven named storms lasted only 24 hours or less. The previous record was six in 2005. Notwithstanding, if this were 40 years ago, many of these short-lived storms would have gone undetected; they certainly would have during the pre-satellite era i.e. before 1966.

My forecast

My best performing forecast for the hurricane season – June 1 to November 30, was the one issued in July, which called for an ACE of 127, with a range of 71-198; 13 named storms, with a range of 9-16; 6 hurricanes, with a range of 4-9 and 3 major hurricane (at least Category 3), with a range of 2-5.

Most powerful and destructive hurricane

Dorian was the most powerful hurricane for this season and many other seasons – past and future. It tied with Hurricanes Wilma of 2005, Gilbert of 1988 and the Labour Day Hurricane of 1935 for second for the most powerful hurricane, based on sustained winds – 295 km/h (185 mph). Only Hurricane Allen of 1990 has had higher winds – 305 km/h (190 mph). However, Dorian became the strongest hurricane, with respect to winds, to make landfall in the Atlantic Basin. In other words, no other land mass in this part of the world, apart from Abaco Bahamas, has ever experienced such high sustained winds.

Dorian about to make landfall on Great Abaco Island , Bahamas – Sep 1, 2019

The season caused over USD 12 billion dollars in damage – the lowest since 2014, with Dorian causing at least 8.28 billion dollars. Of the 8.28 billion, 85% (7 billions) was caused in the Bahamas; this represents around 58% of the total damage for the year.

Hurricane Dorian’s destruction in the Bahamas. Picture courtesy Wikipedia

The death toll is at least 98, with at least 61 dead and at least 400 missing in the Bahamas. The total fatalities for 2019 could be the highest since 2017, when it was over 3300.

Rankings

Looking at the year with respect to the number of named storms – 18. This tied with 1969 for the eighth highest number of named storms for a year. It is the highest number of named storms since 2012.

Ranking of hurricane season by tropical storms (TSs). Graphic courtesy Wikipedia.

The 2019 season is the fourth active season in a row, dating back to 2016; however, 2019 was the least active of the period although it had the highest number of named storms. The main difference is that 2019 had fewer hurricanes.

Relative to the normal season of 12 named storms, 6 hurricanes, 3 major hurricanes and 106 ACE, this season had 50% more named storms than normal but the same number of hurricanes and major hurricanes. The ACE was 23% higher than usual. All metrics indicate that the 2019 season was near or above normal.

Other notable records are:

  • Dorian became the strongest hurricane ever recorded outside of the Caribbean and the Gulf of Mexico – the previous record was held by Hurricane Irma of 2017
  • Dorian impacted the Bahamas for 27 hours as a Category 5 hurricane – the longest ever on record for a Category 5 hurricane to impact one location.

Relative to Antigua and Barbuda

Antigua was brushed by Dorian on August 27, with the system passing about 110 miles southwest of the island. During the passage, it caused wind gusts of 44 to 63 km/h (28 to 39 mph).

The impact on the island was minor, as the system was quite disorganised due to it ingesting dry and dusty air from the Sahara Desert and being battered by hostile wind shear.

On average, Antigua and Barbuda gets one named storm passing within 105 nm every other year, one hurricane every three years and a major hurricane every seven years.

Why was the season active?

The season was active because of warmer than normal sea surface temperatures across the Atlantic and below normal wind shear, particularly during the peak of the seas – August to September.

The absence of an El Nino also allowed for a more active season than normal.

Keep following for more on the just ended hurricane season, tropical cyclones and climate change and all things weather and climate. The next hurricane season starts June 1, 2020 – six months from now, let us all be prepared. Our first forecast for the next season will be issued around April 10.

Please share this blog, if you found it useful and follow me at TwitterFacebook and Instagram.





Hurricane Season History: June

29 06 2019

Dale C. S. Destin|

The first month of the Atlantic hurricane season is coming to a close and the month is yet to see a named storm (tropical storm or hurricane). And as it stands, we are unlikely to see any this June but this is not uncommon.

All 98 Atlantic Named Storms to Have Formed In June – 1851 to 2018

In total, the month has produced 98 named storms on record dating back to 1851; 38 were hurricanes and only 3 were major hurricanes – Category 3 or higher.  

On average, there is a 44% chance of a named Atlantic storm in June, 20% chance of a hurricane and 2% chance of a major hurricane.

In other words, there is a named storm every other June, and hurricane every 5 Junes and a major hurricane every 50 Junes, on average.

From 1851 to present, there have been 75 years with June storms and 93 years without. The June with the most named storms are 2012, 1968, 1936, 1909 and 1886 with three each.

The June with the most hurricanes is 1886. The strongest June hurricane is Alma of 1966 with 205 km/h (127 mph) winds; it did a “number” on Cuba and southeast United States.

The Eastern Caribbean Have Only Had Two Named Storms In June – 1851 to 2018

As the graphic above shows, only three times have we every experienced a named storm across the Eastern Caribbean in June – Tropical Storm Bret in 2017, Tropical Storm Ana in 1979 and an unnamed hurricane in 1933. Bret and the unnamed hurricane impacted Trinidad and Tobago and Ana impacted St. Lucia and Martinique.

Climatological Areas of Origin and Typical Hurricane Tracks for June

Clearly, when storms do form in June, they are likely to develop across the western Caribbean Seas and the Gulf of Mexico – there is very little to no action elsewhere across the basin.

No June Storm has Every Passed Within 120 Miles of Antigua on Record – 1851 to 2018

Quite evident also is that Antigua and Barbuda has never being impacted by a storm or hurricane in June. This may be surprising to many, but it is very much the case and this record is not about to come to an end this year.

This is the second consecutive year no named storm formed in June. The longest streak of no June storm is 7 years – 1947 to 1953. On the other hand, the longest streak of June storms is 8, 2010 to 2017.

Don’t be fouled by a quiet June – it says nothing about the rest of the hurricane season. The probability of an above normal season is similar with or without a named storm in June. Keep your guard up and get or stay prepared. It only takes one storm to ruin your year, if not life.





Tropical Storm in May? Uncommon but not Unheard Of

5 05 2019

Dale C. S. Destin |

The first tropical disturbance for the year has formed and is currently over the Western Atlantic, near the southeast United States. Although this system is unlikely to form, it is not unheard of for tropical storms to develop in May, but it is relatively uncommon.

Looking back at the history, there have been 26 tropical storms in May, 4 of which became hurricanes – all category ones. This means, on average, one tropical storm forms every 6 to 7 years, based on data for the period 1981-2010, upon which the current climate is based.

All Tropical Storms in May on Record, 1851 to 2018

All May Tropical Storms, on Record – 1851 to 2018

The probability of a tropical storm forming in May is 15% (a slight chance), which means storms seldom form in May. The last time this happened was back in 2016 – Tropical Storm Bonnie.

Hurricanes in May are even more uncommon, if not rare. The probability of one forming in May is less than 3%, based on the full history – 1851 to 2018. This means there is a hurricane in May, on average, once every 42 years – once in a generation plus. The last one was Hurricane Alma of 1970.

One may be tempted to think that a tropical storm in May is an omen for an active (above normal) hurricane season. In a (small) poll done by me on twitter, 61% of persons said that a storm in May means an active or hyperactive season; however, this is false. The record shows the following w.r.t. seasons whenever there has been a storm in May:

  • 3 hyperactive;
  • 4 active (above Normal);
  • 11 normal and
  • 5 quiet (below normal).

In other words, whenever there was a storm in May:

  • 4% of the time the seasons were hyperactive;
  • 17% were active;
  • 48% were normal and
  • 22% were quiet.

Hence, a storm in May seems to portend a normal hurricane season, as opposed to an active or hyperactive season. So, we may, perhaps, want to wish for a storm in May.

With all the talk about climate change and tropical cyclones, one may be tempted to think that we are having more storms in May than before. However, the record does not bear that out. In the 38 years from 1981 to 2018, there have been nine tropical storms, no hurricane. By comparison, during the previous 38 years, there were eight tropical storms, two of which became hurricanes.

While tropical storms are not unheard of for the Atlantic Basin, they are unheard of for our neck of the woods – Antigua and Barbuda. We have never been impacted by a tropical cyclone (tropical depression, tropical storm or hurricane) in May.

The fortune of never having a tropical cyclone in May extends to the rest of the Eastern Caribbean. As a matter of fact, none has ever formed east of Hispaniola. Further, no hurricane has ever impacted/affected any Caribbean island in May. Clearly May is not a month to be worried about tropical storms.

Follow me for the latest on the hurricane season and all things weather and climate.





Potential Hurricane Scare Early Next Week

30 08 2016

Dale C.S. Destin |

A weather disturbance coming off West Africa will likely cause a scare to residents of the northeast Caribbean early next week. Two of the more reliable weather models are forecasting this disturbance to become tropical storm or hurricane later this week and track in the direction of the islands.

Tropical Disturbance Moving Off the West Coast of Africa - Aug 29, 2016

Tropical Disturbance Moving Off the West Coast of Africa – Aug 29, 2016

The preliminary forecast track has it moving on a westerly path, in line with the Leeward Islands, which includes Antigua and Barbuda. However, just before reaching the islands, it’s forecast to turn right or north away from the islands, which should spare us its wrath.

ECMWF IFS

ECMWF Integrated Forecast System Showing at least an 80% Chance of a Tropical Cyclone Near the Northeast Caribbean Between Sep 4 and 6

Twenty-one years ago from September 5, 2016, Antigua and Barbuda experienced one of the most powerful hurricanes in its history – Category 4 Hurricane Luis. It brought death and major destruction to the islands. It left in its wake three dead and around US$350 million dollars in damage. It is easily our costliest hurricane in history.

The system that could cause us some stress is not being forecast to be a Luis, God forbid! However, its potential path and timing are reminiscent of Luis. It could be nearest us around September 5, just that this time, it should turn away sooner than Luis did and spare us this time.

The hurricane season runs until November 30. The forecast calls for 15 named storms, 7 hurricanes and 3 major hurricanes. Thus far, there have been seven named storms and three hurricanes, the last one being Gaston. The peak of the hurricane season is around September 10; however, for us, it’s around August 20 and September 3. Become hurricane strong by being prepared!

Follow us via our social media platform and stay updated on the 2016 Atlantic hurricane season. We are available on twitter, facebook, wordpress, instagram, tumblr, and google+. Follow us also for all things weather and climate.





The 2016 Atlantic Hurricane Season Early Forecast

15 04 2016

Dale C. S. Destin |

Early forecasts just issued for the upcoming 2016 Atlantic hurricane season (AHS) indicate a near normal season is most likely. However, relative to the past three years, this season could be much more active.

Ensemble forecast

The ensemble (mean) forecast, based on predictions from Klotzbach of Colorado State University, Saunders and Lea of Tropical Storm Risk.com (TSR) and AccuWeather.com, is for 13 named storms, 6 becoming hurricanes and 3 becoming major hurricanes.

2016_Hurricane_Season_Forecast

A better indicator of the activity for the season is the accumulated cyclone energy (ACE) index which is a measurement of the strength and duration of each tropical cyclone. Summing together the ACE of each cyclone, provides a more complete picture of how active the season is likely to be outside of just the number of storms.

This year, the ensemble forecast calls for an ACE index of 85. If this forecast pans out, the 2016 season would be around 136%, 27% and 35% more active than 2013, 2014 and 2015 respectively.

It must be noted though that there is very low skill in forecasting the AHS (June to November) in April. However, this is the best available forecast for the season, at this time, and can be used as a guide for what is possible. A more skillful forecast will be available around June 1.

End of Atlantic active phase?

Around 1995, the AHS went from a quiet to an active phase. The average annual number of named storms increased from 9 to 15. There is now increasing evidence that we have seen the end of that active phase.

If the active phase has in fact ended, it would mean a reduction in the mean number of tropical cyclones (depressions, tropical storms, hurricanes) across the Atlantic over the next 20 to 30 years. This would translate to an annually reduced probability (chance) of us being impacted by a tropical cyclone between now and around the year 2041.

The x factors

There are at least two climate factors that could cause the hurricane season to be quieter than is currently being predicted. El Nino is ongoing and is virtually synonymous with inactive AHSs. The forecast is for a transition from El Nino to neutral conditions around the middle of the year and possible La Nina around October. However, if El Nino were to persist beyond summer, we would see another quiet hurricane season. On the other hand, La Nina could lead to an active season.

The second potential inhibitor of the 2016 AHS is the transport of cooler-than-normal sea-surface-temperatures (SSTs) into the tropical North Atlantic by ocean currents originating south of Greenland. Reduced SSTs hinder tropical cyclone formation and growth.

Probability of Antigua being hit by a hurricane

According to Klotzbach, the likely best similar years to the upcoming 2016 AHS are 1941, 1973, 1983, 1992, 1998 and 2014. Of these years, we were hit by Hurricane Georges and Tropical Storm Bonnie in 1998 and Tropical Storm Christine in 1973. Thus, based ONLY on similar years, the probability of Antigua being hit this year by one or more named storms is around 39%, while the probability of one or more hurricanes is around 15%.

In general, the probability of Antigua being hit by one or more named storms annually appears to vary according to the phase of the Atlantic. During the quiet phase of 1962 to 1994, the probability of one or more named storms was around 26%, while the probability of one or more hurricanes was around 14%. Meanwhile, for the active phase of 1995 to present, the probability of one or more named storms increased to around 55%, while the probability of one or more hurricanes is around 35%.

Based on the climatological period of 1981-2010, the probability of being hit by one or more named storms is around 41%, while the probability of one or more hurricanes is around 28%.

2015 hurricane season and lessons learnt

The 2015 AHS was quiet; it produced 11 named storms, 4 hurricanes and 2 major hurricanes. The ACE index total was 63, the fourth lowest since 1995. Notwithstanding it being a quiet year, Antigua was affected by Tropical Storms Danny and Erika. Damage was minor; however, closure of the country for around 24-hours, due to threat from Erika, caused an unknown loss of revenue.

Erika serves as a perfect reminder of the fact that flooding is a hazard associated with tropical cyclones. The system caused catastrophic flash floods across parts of Dominica, killing dozens of people. I our part of the world, we tend to focus a bit too much on the wind hazard associated with these systems.

Another lesson learnt was that it only takes one named storm to make it an active or miserable hurricane season for us. Thus, quiet season or not, the same hurricane season preparations are required each year.

Follow us and stay updated on the 2016 AHS via our social media platform, which includes twitter, facebook, wordpress, instagram, tumblr, and google+. Follow us also for all things weather and climate.





Struggling TS Danny

19 08 2015

Dale C. S. Destin |

Recent image of TS Danny

Recent image of TS Danny

Recent images of Tropical Storm (TS) Danny were rather unimpressive in terms of organization (good news for the Caribbean). The system appears to be struggling as dry Saharan air is getting sucked into it. However, strengthening is forecast by the official U.S. National Hurricane Center forecast.

At 11 a.m. this morning, Danny was assessed to have sustained winds of 50 mph about 1400 east of Grenada, in the Windward Islands, and 1435 east-northeast of Antigua, in the Leeward Islands. It was moving west at 12 mph.

Official forecast track

Official forecast track

Danny's track

The models appear to be showing a high degree of certainty with respect to the eventual path of Danny. Almost all the models, I have surveyed, have the system passing over or north of the northeast Caribbean.  This means that Antigua and the rest of the northeast Caribbean could be in the direct line of fire from Danny come Monday.

Danny's intensity guidanceContrastingly, the models are showing considerable uncertainty with the forecast strength of Danny. The official forecast is for it to become a hurricane on Friday. However, the models are split down the middle on the eventual strength of the cyclone with an even chance of it remaining a storm or becoming a hurricane. Becoming a hurricane may become the news worst case scenario.

The models are, however, unanimous on Danny not becoming a Category 2 hurricane, unlike previous forecasts (good news). It could still be of similar strength to Gonzalo, of last year, when it reaches us. There is enough uncertainty to suggest that it may even be a weaker cyclone upon arrival.

The more reliable European Centre for Medium-Range Weather Forecasts (ECMWF) continues to only give Danny a less than 5 percent chance of becoming a hurricane. Further, it gives it a low chance of impacting the islands as a TS. The ECMWF continues to be a source of relatively good news for us.

ECMWF forecast

ECMWF forecast

A hurricane watch will likely come into effect for portions of the northern Eastern Caribbean on Friday followed by a warning Saturday/Sunday. Start or get ready to execute your hurricane plan!

Follow us also on @anumetservice, facebook and tumblr for the latest on the current drought and other weather & climate news.





Early Start to the Atlantic Hurricane Season?

4 05 2015

Dale C. S. Destin |

Notwithstanding the forecast for a quiet Atlantic hurricane season this year, it looks like we will see an early start to the season.

IHG13-22152015124

ECMWF Tropical Cyclone Strike Probability Forecast

ECMWF Tropical Cyclone Strike Probability Forecast

The U.S. National Hurricane Centre is presently indicating a low chance of tropical cyclone (depression, tropical storm or hurricane) formation in the next five days. However, one of the most reliable weather models, ECMWF, is indicating a high chance, up to 70% probability, of a tropical cyclone forming later this week, just north of the Bahamas.

If it forms, it looks likely that it will have an impact of the Carolinas and nearby southeast coastal areas of the United States. At most, they may have to deal with the effects of a strong tropical storm.

Antigua and Barbuda, has not been affected by a preseason storm in over 60 years and that streak is not expected to end this year. Our last preseason system was Hurricane Alice2 in January 1954, which actually formed in December 1953. Most of the rest of the Eastern Caribbean has never had a preseason storm and that is not about to change this year.

The initial disturbance is likely to develop from a cold front currently causing extremely wet weather across portions of the Cayman Islands, Cuba, the Bahamas and south Florida. Already, there has been massive flooding in Cuba causing three deaths and forcing tens of thousands from their homes.

TRMM_Rainfall

TRMM satellite has estimated up to a staggering 300 mm (12 inches) of rain has fallen across parts of Cuba and the rest of the affected area within the past seven days. Another 100 mm (4 inches) is possible over the next three days; hence, more flooding is expected.

It’s relatively rare but not unheard of for tropical storms to form in May. According to AOML, there have been 20 tropical storms in May over the period 1851-2014. This translates to one in every nine-ten years, on average. The last May storms were Alberto and Beryl in 2012.

Preseason tropical cyclones have no known omens for the Atlantic hurricane season. So, whether or not there is an early start, a quiet season is most likely this year, given the existing and expected prevailing atmospheric conditions.

Officially, the Atlantic hurricane season runs from June 1 to November 30.

We will continue to monitor this developing story.





THE ATLANTIC HURRICANE SEASON FORECAST – 2013

3 06 2013

| By Dale C. S. Destin

The Forecast

The general consensus among tropical cyclone experts is for an above normal Atlantic Hurricane Season for 2013. The consensus forecast calls for 16 named storms, 9 hurricanes and 4 major hurricanes. A normal season averages of 12.1 named storms, 6.4 hurricanes and 2.7 major hurricanes (See table 1). The science behind the outlook is rooted in the analysis and prediction of current and future global climate patterns as compared to previous seasons with similar conditions. For this season, the experts are citing a warmer than normal Tropical North Atlantic as the main reason for an above normal season prediction.

AtlanticHurricaneSeasonForecasts2013What does this mean for Antigua and Barbuda?

Although there have been great advancements in the science of tropical cyclone (depression, tropical storm and hurricane), the science has not yet reached the stage where accurate predictions can be made of how many cyclones will form in a given year. Also, the science cannot accurately predict when and where these systems will move or make landfall months in advance. The details of the large-scale weather patterns that direct the path of these cyclones cannot be predicted more than a few days into the future. However, for the current active era (1995 – present), there is around a 39% chance or 4 in 10 chances of one or more hurricanes affecting Antigua (directly or indirectly) this season; this is around 10% above the long term chance.

The 2012 Hurricane Season

The 2012 Atlantic Hurricane Season produced nineteen (19) named storms. Of the nineteen (19) storms, ten (10) became hurricanes and one (1) strengthened to achieve major hurricane status – category three (3) or higher on the Saffir-Simpson Hurricane Wind Scale. The strongest tropical cyclone for the season, in terms of pressure was Hurricane Sandy with peak winds of 110 mph and minimum pressure of 940 mb; however, category 3, Major Hurricane Michael had the highest sustained winds of 115 mph and minimum pressure of 964 mb. Relative to Antigua and Barbuda, Isaac and Rafael brushed Antigua and Barbuda as tropical storms.

A number of records were or nearly broken during the 2012 hurricane season. The season had a hectic start and by June 23 Debby formed and become the earliest 4th named storm on record. Prior to the official start of the hurricane season, June 1, there were two preseason storms – Alberto and Chris – the second time on record two storms form in May in a given year, May 1887 was the only other time. It was also the first time since 1908 two named storms preceded the hurricane season and the third time on record. The most intense hurricane, in terms of lowest central pressure, was Hurricane Sandy; it is also considered the largest known Atlantic hurricane by gale diameter on record. Hurricane Nadine was the fifth longest-lived tropical cyclone on record. In addition, August 2012 was tied with August 2004, September 2002, and September 2010 for most number of named storms in a particular month, at eight.

It Only Takes One

Regardless of the numbers, we should always approach the hurricane season in the same manner each year: be aware and be prepared. The prevention of the loss of life and property from tropical cyclones is a responsibility that should be shared by all. As a reminder, recall our lesson from Hurricane George of 1998: it only takes one hurricane to make it a bad season. Accordingly, the Meteorological Service will play its usual role in alerting the public of any tropical cyclone that may form and threaten Antigua and Barbuda, the Leeward Islands and the British Virgin Islands. We endeavour to provide weather and climate information for the protect life, property, livelihood and the enhancement of the economy. Although the hurricane season officially runs from June 1 through November 30 each year, tropical cyclones can and have occurred outside the season – be prepared!

AnuStorms

PDF Format

References

Accuweather.com, State College, Atlantic Hurricane Season: Three US Landfalls Predicted [online].
Available from: <http://www.accuweather.com/en/weather-news/atlantic-hurricane-forecast-2013/12116274>
[Accessed 3 June, 2013]

Colorado State University, Fort Collins, Extended Range of Atlantic Seasonal Hurricane Activity and Landfall Strike Probability for 2013 [online]. Available from: <http://typhoon.atmos.colostate.edu/Forecasts/2013/june2013/jun2013.pdf> [Accessed 3 June, 2013]

Florida State University, Raleigh, FSU COAP Atlantic Hurricane Season Forecast [online]. Available from:
<http://coaps.fsu.edu/hurricanes> [Accessed 3 June, 2013]

National Oceanic and Atmospheric Administration, Silver Spring, NOAA Predicts Active 2013 Atlantic Hurricane Season [online]. Available from: <http://www.noaanews.noaa.gov/stories2013/20130523_hurricaneoutlook_atlantic.html> [Accessed 28 May, 2013]

North Carolina State University, Raleigh, 2013 Atlantic Tropical Cyclone Outlook [online]. Available from: <http://cfdl.meas.ncsu.edu/research/TCoutlook_2013.html>%5BAccessed 28 May, 2013]

Tropical Storm Risk, London, Pre-Season Forecast for Atlantic Hurricane Activity in 2013 [online]. Available from: <http://www.tropicalstormrisk.com/docs/TSRATLPreSeason2013.pdf>[Accessed 28 May, 2013]

United Kingdom Met Office, Exeter, Seasonal Forecasting of Storms [online]. Available from:
< http://www.metoffice.gov.uk/weather/tropicalcyclone/seasonal/forecasting-method > [Accessed 3 June, 2013]





The Heart of the Hurricane Season

28 08 2012

By Dale C. S. Destin

Every year, persons across the Caribbean, Central America and the US Gulf and Atlantic Coasts pray for this period to pass quickly with out a hit – the heart of the hurricane season, which covers the period August to October (ASO). For the period 1851 to 2011, Antigua has had 93 named storms and 44 hurricane giving and average per year of 0.6 named storm and 0.2 hurricane for ASO. For Antigua, the heart of the hurricane season is August to September, which accounts for 79% (Aug 34%, Sep 45%) of all storms to affect the island. (http://www.antiguamet.com/Climate/climate_anu_cyclonesbyday.html ). This period has had 83 named storms and 41 hurricane for an average per year of 0.5 hurricane and 0.2 hurricane i.e. one storm every other year and one hurricane every five years.

August 21 and September 3 are very peculiar days for Antigua. These are the two peak days for Antigua for the hurricane season with a record of 7 named storms each to have affected the island on those days from 1851 to 2011. September 3 has produced three hurricanes and August 21 has produced four. (http://www.antiguamet.com/Climate/climate_anu_cyclonesbyday.html ) Two notorious tropical cyclones that have struck on August 21 were Category 3 Unnamed Hurricane of 1871 and Category 3 Hurricane Baker of 1950.

On average, ASO has 8 named storms and 5 hurricanes per year. Historically the period has had 1237 named storms of which 806 became hurricanes – 1851 to 2011 – with August contributing 362 named storms and 230 hurricanes; 80% of all storms (Aug  23%, Sep 37%, Oct 20%) form during the period ASO. This year has been no ordinary year contrary to initial forecasts; so far for August, there have been six named storms and three hurricanes, when the month averages two named storms and one hurricane. The record for named storms for August is eight, observed in 2004. The forecast for the overall season has moved from near – below normal to above normal/active season with a consensus of 14 named storms, 6 hurricanes and 3 becoming major hurricanes; already there has been 10 named storms  and 4 hurricanes. (http://www.antiguamet.com/Climate/HURRICANE_SEASON_FORECAST/2012AtlanticHurricaneSeasonForecastAug28.pdf) looks like we will actually see more than 14 when the season ends November 30. Currently, ENSO Positive conditions (El Nino) is trying to squelch of shut down the hurricane season as is the norm; however, the tropical North Atlantic is warming and other factors such as negative North Atlantic Oscillation (NOA) and Arctic Oscillation are in favour of further warming. Of course, there are other factors to consider but these are some of the main drivers of the hurricane season. What do you think will happen? How many more named storms will we see before the season ends?








%d bloggers like this: