Seasonal Forecast: April to June 2021

Date of Issue: March 30th, 2021


Ø Seasonal Forecast: April - May - June 2021 (AMJ)


The usual dry season conditions are expected with a slight increase in the frequency of wet days through April (Wet day: greater than or equal to 1.0mm of rainfall). A reduction in the frequency of rainfall events is expected by the end of the dry season. Less than to the usual rainfall amounts are anticipated for the first half of the wet season (June to August). These conditions may lead to extended dry spells which can result in significant water stresses within the agricultural sector, especially along the western half of the island. A need for irrigation and other water harvesting techniques may be required. Keep updated.


Generally, temperatures are forecast to remain as usual into June. The heat season begins in May and as usual an increase in temperatures is expected by then, but it is expected to remain normal. An increase in temperatures may occur during dry spells. Temperatures are expected to warm significantly thereafter into September. 


Ø Influencing Factors

1.      El Niño Southern Oscillation (ENSO)


Recent observations: Sea Surface Temperatures (SSTs) in the eastern Pacific have warmed slightly. However, temperatures remain colder than usual maintaining a weak La Niña phase.


Model forecast and guidance: A transition to ENSO neutral conditions is forecast during the April-May-June 2021 season. (60% chance).


Expected impacts on rainfall and temperatures: During the dry season (December to May), La Niña tilts the odds to more frequent rainfall events and cooler temperatures. The transition out of La Niña and into ENSO Neutral may result in a reduction of the frequency of rainfall events. This may also lead to a delayed onset of the wet season.


  1. Climate conditions in the Tropical North Atlantic (TNA) and Caribbean Sea


Recent observations: SSTs along the shores of the Caribbean and in parts of the Tropical North Atlantic (TNA) and sub-tropical North Atlantic have cooled slightly, near average to about 0.5°C above average.

Expected conditions: Uncertainties exist in the forecast of the SSTs across the Caribbean Sea and the TNA through June-July-August 2021.

Expected impacts: Continued warm SSTs in and around the Caribbean tends to contribute to above-average humidity, seasonal rainfall totals, reduced dry spell frequency and a potential slightly earlier start of the wet season in the Lesser Antilles.



See table below with Climatological Normal/ Averages




Disclaimer: The Dominica Meteorological Service makes no warranties, either expressed or implied, concerning the accuracy, completeness, reliability or suitability of these products and will not be held liable for any actions taken in reliance thereon. The information is free for use with the understanding that content may not be modified and presented as original material.


Source: Dominica Meteorological Service (DMS) in collaboration with the Caribbean Institute for Meteorology and Hydrology (CIMH) & National Oceanic and Atmospheric Administrative (NOAA)