Dry Season 2020 2021 Cari COF Caribbean Climate
Dry Season 2020 -2021 Cari. COF Caribbean Climate Outlooks Coordination: Caribbean Institute for Meteorology & Hydrology Dr. Cédric J. Van Meerbeeck - Climatologist Dr. Teddy Allen– Assistant Climatologist Mrs. Shontelle Stoute – Technical Officer Mrs. Lisa Kirton-Reed – Technical Officer Dr. Roché Mahon – Social Scientist Ms. Jodi-Ann Petrie – Technical Officer caricof@cimh. edu. bb Participating countries and territories Antigua & Barbuda, Aruba, Bahamas, Barbados, Belize, Cayman Islands, Cuba, Curaçao, Dominican Republic, French Guiana, Grenada, Guadeloupe, Guyana, Haïti, Jamaica, Martinique, Puerto Rico, St. Barth’s, St. Kitts & Nevis, St. Lucia, St. Maarten/St. Martin, St. Vincent & the Grenadines, Suriname, Trinidad & Tobago and the US Virgin Islands
Key Messages 1. Recently: • Intense and record-breaking heat and flooding rains in many areas as regional drought largely subsided amidst the busiest Atlantic Hurricane Season on record. Fueled by warm ocean temperatures and La Niña. 2. The 2020 -21 Dry Season Outlook: • Until March: From April: Cool Season, steady decrease in rainfall and wet days / increase in dry spells. Heat Season with heatwaves & heat discomfort, increasingly intense showers, but frequent dry spells. • Potential for flooding and related hazards Guianas: high during intense wet season Dec. to Feb. (limited in March & April). Belize / Islands: limited to moderate in Dec. , Apr. & May (very limited from Jan. to Mar. ). 3. Prepare for: Initially: After March: Flood-related hazards. Growing water shortages, increasing wild fire potential & heat discomfort.
What to expect in coming months? What usually happens during the dry season? Will it look any different this year?
La Niña and climate in the Caribbean Since September 2020: moderate (to potentially strong) La Niña • La Niña, the cold counterpart of El Niño is… – – – Cooler than normal sea surface temperatures - and higher air pressure - than usual across the eastern equatorial Pacific. Due to ocean currents and winds shift near equator. Occurs every 2 -7 years. • La Niña facilitates deep cloud formation and tilts the odds toward enhanced Hurricane Season activity, tempered temperatures and wetness in the Caribbean… EXCEPT in the north, where La Niña tends to intensify the dry season. • The current La Niña - the strongest since 2011 -, is likely to subside by May or June, but may be followed by another La Niña later on in 2021. El Niño associated with opposite impacts (drought, intense heat, reduced hurricane activity). • La Niña
Any factors driving different climate conditions this year? Persistent, unusually warm sea surface temperatures in the Caribbean Sea and sub-tropical North Atlantic Moderate La Niña; Niña La Niña conditions due to persist through April 2021 boosts heat, humidity, Hurricane Season activity, and flood potential boosts rainfall, Hurricane Season activity and flood potential, but tempers heat Observations of late November SST anomalies (source: NOAA/NCEP) El Niño/La Niña: Recent Evolution, Current Status and Predictions (Source: NOAA CPC / IRI)
How wet will the next three to six months be? December 2020 to February 2021 March t 0 May 2021 FORECAST: • Dec. to Feb. likely at least the usual rainfall amounts in the Guianas and most of the Antilles; but at best the usual rainfall in the Bahamas and Cuba. • Mar. to May likely at least the usual rainfall in Belize, the Guianas, and the Lesser Antilles south of Guadeloupe, but at best the usual rainfall much of the Greater Antilles.
Flood potential from increasingly frequent spells of heavy rainfall December 2020 to February 2021 Frequency of very wet spells What usually happens from Dec. to Feb. ? • Wet spells: 1 to 3 in most places (ABC Islands: 2 to 6; Guianas: 1 to 5), with up to 1 or 2 ending up very wet (ABC Islands & Guianas: up to 3). • Floods: typically, 2 significant floods in the Guianas; 1 signficant flood in some years in other areas. Forecast and Implications: • High potential for flooding, flash floods, land slides / rock fall and soil erosion from very wet and extreme wet spells in the Guianas. • Potential decreasing from moderate to slight in Belize and the islands after December. • Slower than usual depletion of water reservoirs east- and southwards of Hispaniola for the early dry season in the islands.
Heavy rainfall in the next 2 weeks? Forecasts provided by: The WMO Regional Climate Centre – Washington Probability for at least 100 mm rain during week 1: 25 Nov – 1 Dec 2020 • • Moderate flood potential in: highlands of the interior in Guyana, Trinidad Slight flood potential in: the ABC Islands, Guyana, Tobago during week 2: 2 Dec – 8 Dec. 2020 • • Moderate flood potential in: coastal Guianas, northern interior of Guyana Slight flood potential in: Cayman Is. , southern Guyana, Jamaica)
Drought concerns in the Caribbean? Short term drought concerns (end of Feb. 2021) Suggested alert levels for short term drought at the end of February 2021 (covering September 2020 to February 2021) IMPLICATIONS: Long term drought concerns (end of May 2021) Suggested alert levels for long term drought at the end of May 2021 (covering June 2020 to May 2021) • Agricultural impacts of drought should be limited, except in western Belize and northwest Puerto Rico. • Depletion of groundwater and other large reservoirs can potentially pose a concern in Belize and Cuba. Suggested drought alert & action levels
How hot will the next three to six months be? Mar-Apr-May 2020 Dec-Jan-Feb 2020 -21 Night time Milder Usual Day time Hotter Milder Usual FORECAST: 1. Comfortably cool conditions from December to March. 2. Temperatures becoming uncomfortably high during heatwaves from April or May. 3. April and May potentially very hot in Belize and Cuba. Hotter IMPLICATIONS: • Little to no heat discomfort until mid-March. • Heat stress in the vulnerable population & small livestock from April (Belize, Cuba & Trinidad) or May (elsewhere). • Cooling need may be increased from April onwards, particularly in the northwestern Caribbean.
How trustworthy are the forecasts? How good are they?
HOW GOOD ARE THE FORECASTS? 1. Long term drought situation by the end of May 2020 Forecasted drought alert levels as first issued in Nov. 2019 Observed drought in orange and red Forecasted drought alert levels as updated in Feb. 2020 1/8/2022 12
HOW GOOD ARE THE FORECASTS? 2. Temperatures during Dec. -Jan. -Feb. 2019 -20 Observed temperature category Forecasted temperature probabilities by category
The Climate Outlooks in summary
The 2020 -21 Dry Season Outlook Dec. to Feb. : Caribbean Islands - less intense early dry season (except Bahamas & Cuba); Guianas - intense wet season. Mar. to May: Increased dryness; rising temperatures and shower intensity from April. 1. Cool season (December to March) with comfortable temperatures, Heat season (from April / May) with heatwaves and increasing heat discomfort. 2. Steady decrease in rainfall and wet days / increase in dry spells towards March, limiting crop productivity and increasing potential for wild fires, particularly in The Bahamas and Cuba, but posing a reduced risk in the eastern Caribbean compared to most other years. 3. Increasingly intense showers from April onwards, despite high dry spell frequency. 4. Potential for flooding / flash floods, landslide / rockfall & soil erosion high in Guianas (limited in March & April); moderate in Belize and the Islands in Dec. , Apr. and May (very limited from Jan. to Mar). 5. Fewer concerns for drought and water availability than in 2019 -2020 dry season.
Keep yourself updated • Make your national Meteorological Services your go-to partner for local climate information • The Caribbean Regional Climate Centre provides additional regional information
Keep yourself updated Our bulletins aim to offer more digestible overviews: Cari. COF Climate Outlook Newsletter Click here Caribbean Coral Reef Watch Click here Caribbean Drought Bulletin Click here
Keep yourself updated Our bulletins aim to offer more digestible overviews: Caribbean Tourism-Climatic Bulletin (since 2017) Caribbean Health-Climatic Bulletin (since 2017) Caribbean Agro-Climatic Bulletin of the Cari. SAM
Keep yourself updated National Hydro-Meteorological Services offer local climate information:
Regional climate data, information, tools, experimental and operational products are available at Thank you rcc. cimh. edu. bb
- Slides: 20