Seasonal Forecast: March to May 2021

Date of Issue: March 1st, 2021

Drought like conditions possible by the end of May 2021, especially along the western half of the island.


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: The models favour La Niña to continue into March-April-May 2021 season (55% confidence). A transition to ENSO neutral conditions is anticipated by the end of the season (60% confidence).

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.


  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 are around 0.5°C to 1°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.


Ø Seasonal Forecast: March - April - May 2021 (MAM)



We are now entering the second half of the dry season. The usual dry season conditions are expected with a slight increase in the frequency of wet days (Wet day: greater than or equal to 1.0mm of rainfall). A drier pattern is expected towards the end of the season which may result in drought like conditions more so along the western half of the island. The chances of having at least one 3-day extreme wet spell exists (medium confidence). Keep updated.


Generally, temperatures are forecast to remain as usual with slightly cooler than usual daytime highs. The heat season begins in May and as usual an increase in temperatures is expected by that time.


 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)