The Barbados-based Caribbean Climate Outlook Forum (CariCOF).says the early wet season is forecast to bring an increase in wet days and wet spells and that there is no major concern for shorter-term drought by the end of August in the Caribbean
In its latest Caribbean Climate Outlooks bulletin released here on Tuesday, CariCOF said that the increase in wet days and wet spells over the next three months will result in a decrease in dryness, wildfire potential and dust levels, as well as an increase in water levels in soils, rivers and reservoirs.
“However, the potential for flash floods, long-term flooding and cascading impacts will increase from moderate to high by August in the islands, while it will decrease from high to moderate in the Guianas. “Heat discomfort, brought about by high temperatures peaking during recurrent heatwaves and increasing humidity in the air, will likewise increase towards August. A similar increasing trend in tropical cyclone activity is expected, with a busy Atlantic Hurricane Season on the forecast,” CariCOF added.
.It said that as of May 1, moderate (or worse) shorter-term drought has developed in most parts of Antigua, most parts of The Bahamas, southwest Belize, Cuba, Hispaniola, St. Kitts, Sint Maarten/St-Martin. It noted that moderate (or worse) long term drought has developed in southwest Belize, along the southern coast of Hispaniola, St. Croix, St. Kitts and the west coasts of the Windward Islands.
“There is no major concern for shorter-term drought by the end of August in the Caribbean,” CariCOF said, noting however that long term drought by the end of November may possibly develop in west-central Belize and in St. Vincent and the Grenadines by the end of November this year.
In its climate outlook for the period, September to November, CariCOF said that during the late wet season, the number of very wet and extreme wet spells reaches its annual peak across Belize and the Islands, with a high potential for flooding and flash floods, as well as, cascading hazards.
“This is with the exception of the Guianas, which will be in their long dry season until mid-November. If the La Niña event re-emerges, the region can expect to be at least as wet or even wetter than usual, with the potential for a busy second half of the Atlantic Hurricane Season. Heat stress is expected to be high until October due to high temperatures and humidity, particularly during recurrent heatwaves,” it added.
Meanwhile, the Barbados-based Caribbean Institute for Meteorology and Hydrology (CIMH) said that there will be strong tropical cyclone activity through October.
CIMH climatologist, Cédric Van Meerbeeck, said that the institute, which began issuing its own hurricane forecast last year, has a high level of confidence that of the 18 storms forecast for this year’s Atlantic Hurricane season, eight will become hurricanes and four major hurricanes.
CIMH has divided the hurricane season into three parts: the first and second halves and the peak season, which spans sections of the halves.
Speaking at the regional climate outlook forum for the wet season, Van Meerbeeck said that CIMH has medium statistical confidence in its forecast that seven named storms will develop in the first part of the season.
There is high confidence that there will be 13 named storms during the peak season, and medium confidence of 10 named storms during the second half of the season.
“The strong consensus is that it will be an active season. To tell you the truth, when I look at these forecasts, I don’t expect anybody to remember all those numbers but those numbers reflect very strongly the forecast we had in May last year for last hurricane season,” Van Meerbeeck said, noting that the forecast was coming just ahead of the beginning of the hurricane.
“So there is still some uncertainty which is why we also update these outlooks over the month,” he said, noting that CIMH will update its forecast in August.
“But you can already see that in the new climatological period, which is 1991 to 2020, there are, annually, about 14 storms of which seven are hurricanes and three ends up being major hurricanes. “
Van Meerbeeck noted that Colorado State University (CSU) on April 8, forecast 17 named storms, including eight hurricanes and four major hurricanes.
CSU suggested a 58 per cent probability that at least one major hurricane will track into the Caribbean this year. This is compared to the long term average confidence of 42 per cent.
Tropical Storm Risk (TSU), another forecast agency, in its April 13 outlook, forecast 17 named storms, six hurricanes and three major hurricanes tracking through the region. The Weather Company, in its April 16 outlook, predicted 19 named storms, eight hurricanes and four major hurricanes.
The U.S. National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center, in its May 20 forecast, has 70% statistical confidence in its outlook that there will be 13 to 20 named storms.
NOAA is forecasting that there will be six to 10 hurricanes and three to five major hurricanes this season.
“But what you can see is that all of the centres that are represented here, there are many more but all of them converge to the idea that there might be somewhere around about 18 storms in this season, of which eight will be hurricanes and about three to four being major hurricanes,” Van Meerbeeck said, adding “you can see that all of the forecasting centres suggest a more active season.”
CSU forecast a 58 per cent probability of at least one major hurricane (Cat 3, 4 or 5) tracking into the Caribbean. This compares to the average probability of 42 per cent between 1901 and 2000.
Van Meerbeeck said that the region is entering the wet season in a very different way than last year.
“Last year, we entered into it with a lot of heat, a lot of droughts, and, later in the season, a lot of tropical storms,” Van Meerbeeck said.
“Now, what we are seeing is that drought is definitely not as expansive but it does exist in pockets of the Caribbean and there are places in the Caribbean that were really particularly wet going into the wet season. So the situation is quite different this year.”
As it relates to heat in the regions, Van Meerbeeck said that with a warming climate, the Caribbean heat season is rapidly expanding.
This is the period of the year when the temperature tends to be warmer and there are heatwaves
“And even though before 1995 it only lasted for about three months a year, nowadays it is already seven months – from April or May to October,” he added.