Date of Issue: January 19th, 2024

 

What are the usual JFM conditions?

 

What is the forecast for this JFM season?

Rainfall

• Uncertainties exist from recent model runs, however, drier than to the usual rainfall amounts are expected into March. A transition to wetter than usual conditions is likely during the April to June 2024 Season (Low confidence).
  
  
• A decrease in the frequency of wet days and 7-day wet spells is likely (medium to high confidence). About 20 to 60 wet days and two 7-day wet spells are forecast.
  
  
• Slight to moderate potential for flash floods.
  
  
• This could lead to fewer outdoor activity disruptions, drier surfaces and vegetation, in turn making environmental conditions less conducive to moisture-related pests.
  
  
• At least three 7-day dry spells and one 15-day dry spell are likely (up to 60% confidence).
  
  
• The possible maximum number of 7-day dry spells is 6.
  
  
• The possible maximum number of 15-day dry spells is 2.
  
  
• At this time, there is a drought watch alert until the end of March 2024.
  
  
• Water conservation techniques should be implemented especially along the western half of the island where rainfall amounts are usually lower. Continue to monitor and keep updated.

 

Temperature

•  Temperatures are expected to be higher than usual as the cool season progresses.
  
  
• No significant episodes of heat stress are expected during the Caribbean Cool Season. However, given persistently higher than usual temperatures, heatwave potential increases as early as March 2024.
  
  
• Higher temperatures combined with dry conditions increase bushfire chances as early as March, especially along the northern and western coasts. 

 

What factors are influencing this forecast?

1.      El Niño Southern Oscillation (ENSO)

Recent observations: Sea Surface Temperatures (SSTs) in the eastern equatorial Pacific have exceeded 1.5°C above average, suggesting a strong El Niño phase. 

 

Model forecast and guidance: Forecast models indicate El Niño during JFM (100% confidence). A possible transition to an ENSO neutral phase is expected by the April-May-June 2024 season (~40% confidence).

 

Expected impacts on rainfall and temperatures: El Niño often results in a warmer cool season with lower than usual rainfall totals across the eastern Caribbean. 

 

 

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

 

Recent observations: Record high temperatures of about 1°C to 2°C above average were observed in much of the Tropical North Atlantic (TNA).  

Expected conditions: Anomalously warm SSTs of 0.5°C to 2°C (or more) above average are forecast across the Caribbean Sea and the TNA.

Expected impacts: Air temperatures and humidities across the Caribbean tend to be higher when SSTs are warm. This then results in above-normal seasonal rainfall totals and an increase in the frequency of extreme rainfall events. 

 

Note: The level of forecast accuracy and certainty decreases as the time increases. This is inherent to all model projections. Therefore, there is less confidence after 48 hours. Model projections may change significantly daily.