“A moderately strong El Niño may develop in November 2023 and continue into April 2024 with possible weakening afterward…” —T&T Met Service
Trinidad and Tobago can expect El Niño conditions to continue throughout November and into April next year, according to the latest ENSO Monitor Update from the T&T Meteorological Service.
Met Service meteorologists forecast that the country may experience less rainfall over the next six months.
“Climate models have indicated with a high probability (75%-85%) that a moderately strong El Niño event may develop in November and continue into April 2024 with possible weakening afterward,” the Met Service update explains.
The Met Service also notes:
“A moderately strong El Niño event increases the likelihood of El Niño related climate anomalies to occur but does not necessarily equate to stronger impacts locally. However, historically El Niño conditions tend to produce below-normal rainfall within Trinidad and Tobago, but not always.”
“There is a moderate probability (68%) that the El Niño conditions will likely have a negative influence on local rainfall during the months of November 2023 to January 2024,” the update says.
EL NIÑO FAQs
A La Niña (El Niño) is declared when the average SSTs in the central and eastern equatorial Pacific Ocean become at least -0.5oC cooler than average (0.5oC warmer than average) in the preceding month and the cooling (warming) is expected to persist for five consecutive overlapping three-month periods. This must occur together with a corresponding change in the overlying atmospheric circulation.
The TTMS La Niña/El Niño Watch is activated when the ENSO Outlook indicates a probability of approximately 50% chance or greater for the development of La Niña or El Niño.
Image courtesy T&T Meteorological Service.
What is El Niño?
A naturally occurring phenomenon involving unusual warming of sea-surface across the central and eastern equatorial Pacific. It has a major influence on weather and climate patterns in various parts of the world. The El Niño, meaning “boy child” in Spanish, was first used in the nineteenth century by fishermen in Peru and Ecuador to refer to the unusually warm waters that reduced their catch just before Christmas.
How often does El Niño typically occur?
El Niño episodes typically occur every two to seven years.
How long does El Nino typically last?
El Niño events often begin in the middle of the year with large-scale warming of surface water in the central and eastern equatorial Pacific Ocean and changes in the tropical atmospheric circulation (i.e. winds, pressure, and rainfall). In general, El Niño reaches a peak during November–January and then decays over the first half of the following year. El Niño episodes typically last nine to 12 months but can sometimes last for years.
El Niño Intensities
An El Niño event requires Oceanic Nino Index (ONI) values to be greater than the 0.5 threshold for at least five consecutive months. El Niño events are categorized as Weak (with a 0.5 to 0.9 sea surface temperature (SST) anomaly), Moderate (1.0 to 1.4), Strong (1.5 to 1.9) or Very Strong (≥ 2.0) events.
Past strong El Niño Events
The previous years where strong events occurred are 1982/1983, 1987/1988, 1991/1992, 1997/1998 and 2015/2016.
What impact does El Niño have on Trinidad and Tobago?
El Niño’s impact on Trinidad and Tobago’s rainfall and temperature is not uniform but varies not only from location to location and from season to season, but also from one El Niño event to another. The outcomes of each El Niño event depend on the intensity of the event, the time of year when it develops, and the interaction with other climate influencers.
The phenomenon is usually associated with drier and warmer local dry seasons. This often means less rainfall, increased odds for dry spells and drought-like conditions, as well as an increase in the number of bushfires in Trinidad and Tobago.
In general, Trinidad and Tobago tends to experience a drier wet season in the year when an El Niño starts and an exceptionally dry, dry season in the year of the decline of the El Niño. Also, in the year of El Niño decline, the start of the local wet season tends to be earlier and more intense.
