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.

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