The Trinidad and Tobago Meteorological Service (TTMS) is forecasting an above-average 2024 Atlantic Hurricane Season. While systems may form within the TTMS area of interest, it only takes one storm to directly impact the country for it to be an active hurricane season.
What you need to know
— The Forecast: Between the eastern Caribbean and the west coast of Africa, south of 15°N, the TTMS is forecasting between three and eight named storms, with six named storms most likely forming and one to four of those becoming hurricanes, with three hurricanes most likely.
— How confident are they? The TTMS has a 58% chance of above-normal, a 10% chance of below-normal, and a 32% chance of near-normal activity.
— What should you do? Any tropical cyclone that forms in the area of interest has the potential to threaten Trinidad and Tobago and the remainder of the Eastern Caribbean. A season only needs one tropical cyclone to cause devastation in T&T and the remainder of the region. Citizens are advised to increase preparation ahead of the 2024 Atlantic Hurricane Season’s peak.
The Forecast Background
Since 2013, the Trinidad and Tobago Meteorological Service has been issuing seasonal forecasts for Trinidad and Tobago’s area of interest (AOI) for tropical cyclone activity.
The Met Office has defined T&T’s AOI as south of 15°N latitude, between the eastern Caribbean and the west coast of Africa, within the north Atlantic Ocean. According to the Met Office, only tropical cyclones forming in this area have been known to directly threaten Trinidad and Tobago.
The North Atlantic Hurricane Season officially runs between June 1st through November 30th, but out-of-season systems have formed in the past, like January last year.
Based on the 1991-2020 climatological average, four named storms formed in this area, one of which generally become a hurricane.
In 2023, the TTMS forecast called for two to six named storms, with four named storms most likely forming and one to three of those becoming hurricanes, with two hurricanes most likely within the AOI. However, 12 named storms formed in the AOI, two of which became hurricanes.
The 2024 Hurricane Season Forecast For T&T
According to the Trinidad and Tobago Meteorological Service, there is a 58% chance of above-normal, a 10% chance of below-normal, and a 32% chance of near-normal tropical cyclone activity in the area of interest for T&T.
The TTMS is predicting that the most likely number of named tropical storms (tropical cyclones with winds of at least 34 knots, 39 MPH, or 63 KM/H) to occur within the AOI from June through November is six.
The most likely number of hurricanes (tropical cyclones with winds of at least 64 knots, 74 MPH, or 119 KM/H) predicted to occur within the AOI from June through November is three.
How does the forecast work?
According to the TTMS, the seasonal tropical cyclone predictions for T&T’s AOI are based on:
- Canonical Correlation Analysis and Principal Component Analysis to predict the number of storms based on sea-surface temperatures (SSTs) in oceanic regions, which are known to have strong correlations with tropical cyclone activity in the AOI;
- Analog years based on sea-surface temperature gradients.
The Met Office says its methodology considered three primary climate drivers, SST gradients, which are known to be responsible for annual tropical cyclone variability in the North Atlantic Ocean.
They explained that the three SST drivers of tropical cyclones are the El Niño-Southern Oscillation (ENSO), which is the known primary cause of variability in tropical cyclone activity in T&T’s AOI, the SSTs during March and April in the waters surrounding Trinidad and Tobago, which is that portion of the extension of the North Atlantic Warm Pool to the east and southeast of Trinidad and Tobago, and the SST gradients within the Atlantic Meridional Mode (AMM), which is north/south gradient in SSTs near the location of the mean Intertropical Convergence Zone.
Current Conditions
Currently, SSTs east of Trinidad and Tobago to the west coast of Africa are well above average, nearing record heat. This heat will lead to stronger tropical waves and the eventual northward movement and strength of the Intertropical Convergence Zone (ITCZ) into the eastern Caribbean.
In the Pacific Ocean, sea surface temperatures are above normal, but a La Niña Watch is in place for the eastern-central Pacific Ocean, with signs that the El Niño is weakening. The TTMS says ENSO neutral conditions are possible by June, and there is a high potential for a La Niña between June and August 2024 and an even higher potential between July and September 2024.
The TTMS explained that La Niña will likely affect local conditions in the coming months, with wetter-than-normal conditions in the late Wet Season and early Dry Season.
Furthermore, the north-south SST gradients, known as the Atlantic Meridional Mode (AMM), are currently positive and likely to continue through September 2024. A positive AMM is associated with enhanced ITCZ activity shifting further north and reducing upper-level westerly winds across the Atlantic Main Development Region
What does this mean for you?
Those who reside in Trinidad and Tobago know that a tropical storm or hurricane can devastate the country. In 2022, the Caroni River overtopped five times within a month without a single direct hit from a tropical cyclone. Tobago experienced its wettest August on record, while Trinidad experienced its wettest November on record.
Though above-average tropical cyclone activity is forecast for T&T’s AOI, tropical waves, troughs, and the Intertropical Convergence Zone have been known to bring flooding rainfall to a highly flood-vulnerable country.
Use this dry transitionary month into the upcoming 2024 Wet Season to prepare your emergency kits and emergency plans and clean your surroundings. Know your emergency numbers in the event of a disaster, and for those living in a flood-prone area, know where you can readily access sandbags in the event of prolonged, heavy rainfall. The Office of Disaster Preparedness and Management also has a guide available to help prepare you for the upcoming Wet and Hurricane Season.
