The Intertropical Convergence Zone (ITCZ), two low-level troughs, and tropical waves are forecast to move across Trinidad and Tobago this week, keeping scattered showers and thunderstorms on tap for the country. However, with moderate concentrations of Saharan Dust lingering across the country, significant rainfall is not forecast.
What you need to know
— Rainfall: Through Sunday morning, forecast models indicate across the western areas of Trinidad and across Tobago, rainfall totals between 15 and 35 millimeters are likely, while across the eastern and southern halves of Trinidad, rainfall totals between 25 and 50 millimeters are forecast. In isolated areas across Trinidad, five-day rainfall totals may exceed 75 millimeters.
— Saharan Dust: Mild to moderate Saharan Dust is forecast across T&T through Tuesday afternoon and again from Wednesday afternoon through the end of the week.
— Hazards: Over the next five days, localized street/flash flooding and brief gusty winds are forecast to be the main hazards in isolated heavy showers and thunderstorms. In and ahead of heavy showers or thunderstorms, sustained winds can reach 35 KM/H, particularly from Thursday. Wind gusts are likely to reach 45 KM/H in heavy showers/thunderstorms, and from Thursday, higher gusts are possible.
— Marine: Seas are forecast to be moderate, with waves in open waters ranging between 1.5 and 2.0 meters, while in sheltered areas, up to 1.0 meter and occasionally choppy.
Latest Alerts
Hazardous Seas Alert Discontinued For T&T
Trinidad and Tobago is NOT under any tropical storm or hurricane threat, watch, or warning at this time.
The Forecast
Monday (PM)
Monday (PM)Tuesday
TuesdayWednesday
WednesdayThursday
ThursdayFriday
FridaySaturday
SaturdayMarine Forecast
Seas Forecast: Moderate Seas, Reduced Visibility
Temperatures
While temperatures are forecast to be warm through the week, rainfall chances remain elevated which may prevent maximum high temperatures from exceeding 32°C, though it will feel warmer.
Wednesday through Sunday
Low: 24-27°C
High: 31-34°C
Maximum high temperatures are forecast to range between 30°C to 33°C, with higher temperatures across urbanized areas of Trinidad, where in built-up areas, maximum high temperatures could exceed 33°C, particularly on Thursday. Minimum lows are forecast to remain mild, ranging between 24°C and 27°C in Trinidad and Tobago, trending cooler in interior areas. The heat index will generally be near or above 34°C through the forecast period.
Forecast Impacts
Flooding
FloodingForecast Rainfall Totals
- Monday: Between 5 and 10 millimeters across both islands and totals between 10 and 20 millimeters across eastern, southern, and isolated northwestern areas of Trinidad, as well as eastern Tobago.
- Tuesday: Between 0 and 5 millimeters of rain across Trinidad and Tobago, with less rainfall across the western half of Trinidad. Across southern and eastern areas, totals between 5 and 10 millimeters are forecast.
- Wednesday: Between 5 and 15 millimeters of rainfall is forecast across the country, with isolated areas of Trinidad receiving between 20 and 35 millimeters of rain.
- Thursday: Less than 5 millimeters of rainfall forecast across the country. A mostly dry and rain-free day.
- Friday into Saturday: Between 5 and 20 millimeters across the country, with totals between 10 and 25 millimeters favoring eastern and southern areas of Trinidad and eastern areas of Tobago. In isolated areas, rainfall totals may exceed 25 millimeters.
Understanding Rainfall Rates
Understanding Rainfall Accumulations
Putting the rainfall forecast into context, rainfall rates in excess of 50 millimeters per hour or areas that receive in excess of 25 millimeters within an hour tend to trigger street flooding across the country or flash flooding in northern Trinidad. For riverine flooding to occur, a large area of the country (not just in highly localized areas of western coastal Trinidad) would have to record upwards of 75 millimeters within 24 hours, and rainfall would have to fall across major rivers’ catchment areas.
Strong Thunderstorms
Strong ThunderstormsWhat is a strong or severe thunderstorm?
Given how rare these types of thunderstorms are in our region – we classify a severe or strong thunderstorm as one that produces any of the following:
- Damaging wind gusts exceeding 55 KM/H;
- Frequent lightning (more than 30 cloud-to-ground strikes within a 10-minute period);
- Hail (of any size);
- Rainfall of more than 50 millimeters or more within an hour or exceeding 75 millimeters or more within three hours;
- The sighting of a funnel cloud or touchdown of a waterspout/tornado associated with the thunderstorm.
Gusty Winds
Gusty WindsPossible impacts include localized wind damage to trees, power lines, and small structures. Small potted plants may blow over with light outdoor objects becoming airborne in stronger gusts. Tents may jump.
Other Hazards
Saharan Dust Forecast
Major Saharan Dust Surge Now Moving Across T&T
Why I May Not/Will Not See Rainfall?
A frequent complaint is the forecast is wrong because I didn’t experience any rainfall. Scattered showers mean that you, individually, may experience some showers intermittently throughout the day, and there is a higher chance for this activity than isolated activity. Widespread showers mean that nearly all persons and areas may experience rainfall.
Throughout the week, isolated to scattered rainfall is forecast, outside of Thursday, where highly isolated rainfall is forecast, interrupting a mostly dry day.
Forecast Discussion
On Monday into Tuesday, a low-level trough interacting with the Intertropical Convergence Zone (ITCZ) is forecast to produce cloudiness, showers, and isolated to scattered thunderstorms across the Windwards.
While conditions are forecast to briefly settle into Tuesday night, high levels of moisture and moderate instability will support showers and thunderstorms as Tropical Wave 22 moves across the Lesser Antilles late Tuesday into early Wednesday, with trailing convergence and the ITCZ fueling another round of rainfall across the country.
By late Wednesday, although the ITCZ will linger, a surge of Saharan Dust is forecast to move in as a high-pressure system rebuilds across the region. Still, isolated showers/thunderstorms are possible due to the diurnal peaks of the ITCZ.
A mostly settled, breezy, and hazy Thursday is forecast as that high pressure remains dominant, but with a nearby ITCZ, there is still the chance for isolated showers or the odd thunderstorm with pockets of low-level convergence.
On Friday, the low-latitude Tropical Wave 23 is forecast to move across Trinidad and Tobago into Saturday while interacting with the ITCZ and under generally favorable upper-level conditions. As a result, scattered showers and thunderstorms are forecast to move across the country through the first half of Saturday. During this 48-hour period, wind shear is forecast to be moderate to strong, preventing persisting shower/thunderstorm activity while keeping overall higher rainfall totals across southern and eastern offshore areas.
A high-pressure ridge will regain dominance by late Saturday, leading to a mostly settled night.
