• What can we usually expect during this period?
  • Climatically, December to February forms the first half of the Dry Season in the Caribbean Islands, Belize, and the far interior of the Guianas. The historical record shows that the first half of the Caribbean Dry Season in the Bahamas, Belize, the Greater and Lesser Antilles is usually characterised by a steady decrease in the frequency of wet days and in the intensity of heavy showers. Conversely, the number of dry days and dry spells is high westwards of Puerto Rico throughout the period while, further east, their frequency increases towards the end of February. The resulting drier surface and foliage increases wildfire potential and the concentration of airborne particulates and local dust levels. Access to more detailed forecast information on dust and air quality in the Caribbean may be found here: http://dafc.cimh.edu.bb/.
  • By contrast, the northeastern two-thirds of the Guianas are in their secondary Wet Season until early February, then moving into their secondary Dry Season. Hence, wet days and wet spells are usually frequent while dry spells are few in December and January.
  • In this period, flood and flash flood potential (i.e., the chance of occurrence of an excessive rainfall event that can trigger floods and cascading impacts – such as land slippage, rock fall, soil erosion, river damming, mud flows – in flood-prone areas) is typically high (i.e., occurs at least once every two years) to extremely high (i.e., occurs in most years) in the Guianas and southern Belize, but slight (i.e., occurs once every five to ten years) to moderate (i.e., occurs at least once every five years) elsewhere.
  • The 2025 Atlantic Hurricane Season officially ended on November 30th, but the historical record shows that storms and hurricanes have occurred after the official end date (e.g., an unnamed sub-tropical storm in January 2023).
  • December to February further marks the return of the entire Caribbean region to the Cool Season. Generally, more comfortable temperatures and decreasing humidity levels are the historical norm for this period.
  • Across the region, swells, surges and rip currents from large, mostly extratropical cyclones in the North Atlantic can be hazardous to life and engender beach erosion. (Seven-day forecasts of swell heights may be found here: WaveWatch III (cimh.edu.bb)
  • Notwithstanding that it is the coolest part of the year, there remains a high risk of skin damage due to intense ultraviolet (UV) light emitted by the sun. The UV index will be high in the northern Bahamas (7-8) and very high (9-10) elsewhere in the Caribbean until January, and then increase to very high and extremely high in those areas, respectively, by February.
  • The frequency of Saharan dust incursions into the Caribbean tends to be low during this period. However, in recent years, an increase in significant episodes as early as February has been observed.

• What is different this year?
  • Ocean temperatures in and around the Caribbean are warmer than average and are forecast to remain so. Due to these unusually warm waters in the Tropical North Atlantic Ocean, air temperatures and humidity during the Cool Season are likely to be higher than usual, but unlikely to the point of significant heat stress.
  • In recent months, cooler than average temperatures have appeared in the tropical Pacific Ocean, with conditions now being borderline La Niña. This La Niña is forecast to subside by March or even before then. Borderline La Niña conditions do not tend to significantly affect the Caribbean. If anything, they are associated with increased heavy shower activity and rainfall totals in the southeastern Caribbean – including the Guianas -, and a more intense early dry season in the northwestern Caribbean.
• In light of the unusually warm North Atlantic, the forecast for December 2025 to February 2026 further suggests:
  • The forecast for seasonal rainfall amounts over the three-month period are uncertain at this point.
  • However, relatively dry air above the Tropical North Atlantic dominated through September, which had led to long-term drought in many areas – particularly in Barbados and the Windward Islands -, exacerbated by (near-)record heat in several locations.
  • Despite the pre-existing long-term drought in multiple areas of the Caribbean, short-term drought is expected to be a significant concern by the end of February 2026 only in northwest Puerto Rico, and the U.S. Virgin Islands (medium to high confidence). However, short-term drought might possibly develop or continue in the ABC Islands, Dominica, Martinique, Saint Lucia, and Tobago (medium confidence). Short-term drought may impact food production, water quality and quantity from small streams, small ponds and other surface sources.
  • Long-term drought is evolving in southwest Belize, Grand Cayman, Grenada, Dominica, Martinique, and Saint Lucia (high confidence) and might possibly develop or continue in the ABC islands, southeast Belize, and St. Vincent (medium confidence). Long-term drought (on a 12 months timescale) affects water availability across a multitude of socio-economic sectors in countries where the main freshwater resource is from very large rivers, large reservoirs or groundwater.
  • Despite the return to the Caribbean Cool Season, seasonal night-time and day-time temperatures in the region are expected to be warmer than usual (high confidence) and accompanied by higher than usual levels of air humidity (medium confidence).
  • Whereas tropical cyclone activity typically decreases after mid-October, severe weather systems related to tropical cyclones, as well as heavy showers can still affect Caribbean territories, particularly during December. The warm Atlantic and possible La Niña conditions increase flood and flash flood potential from high to extremely high in Belize and Guyana, high in the Windward Islands, and moderate to high in the ABC Islands and the small islands or low-lying areas of the Leeward Islands. Persons should keenly monitor weather advisories issued by the National Meteorological Services and other information provided by the Caribbean Disaster Emergency Management Agency (http://cdema.org/) and the US National Hurricane Center (https://www.nhc.noaa.gov/).

This Bulletin provides a broad overview of climate conditions up to 3 months in advance. It is based on insights drawn from CIMH’s suite of technical climate information products and epidemiological insights from CARPHA and PAHO. The information contained herein is provided with the understanding that the CARPHA, the PAHO and the CIMH make no warranties, either expressed or implied, concerning the accuracy, completeness, reliability or suitability of said information. The Bulletin may be freely used and disseminated by the public with appropriate acknowledgement of its source but shall not be modified in content and then presented as original material.