Forecast: Cooler Nighttime Temperatures & Sunny Skies Until Sunday

Dry air will remain across T&T through the next 24 hours, with a shearline forecast to affect the country by Sunday. Here is what you need to know:

— Through Friday night, a relatively dry and stable atmosphere is forecast to prevail across Trinidad. Nighttime lows are forecast to be near 19°C to 23°C across the country with daytime highs near 31°C to 32°C. Increasingly cloudy skies likely by the evening.
— On Saturday, a brief surge of moisture accompanied by a surge in winds is forecast to bring low-level cloud patches and a few brisk showers, but no significant rainfall is expected.
— From Sunday through next week, a shearline is forecast to linger and gradually dissipate across the Windwards, including T&T bringing periodic cloudy skies and brisk showers.
— Generally, no major hazards or Saharan Dust surges are expected.
— Sustained winds up to 35 KM/H with wind gusts up to 45 KM/H accompanying showers are likely, with gusts in excess of 50 KM/H possible.
— Seas are forecast to be moderate, with waves between 1.5 to 2.5 meters and less than 1.0 meter in sheltered areas.
— There are no alerts, watches, or warnings in effect for Trinidad and Tobago from the Trinidad and Tobago Meteorological Service at this time.

The Forecast

High atmospheric moisture moving away from Trinidad and Tobago. (SSEC/CIMSS/UW-Madison)

Generally, any heavier showers will favor eastern areas of Trinidad and Tobago through the forecast period.

Thursday night: Mostly clear and cool conditions.

Friday (New Year’s Eve): Mostly sunny, breezy/windy, with increasing cloudiness by the evening and brisk showers possible overnight.

Saturday (Near Year’s Day): Mostly sunny and breezy with brisk showers favoring eastern Trinidad. Increasingly cloudy conditions are forecast by nightfall.

Sunday: Variably cloudy skies with brisk showers and an overall breezy day. Gusty winds may accompany showers, with heavier rainfall favoring eastern and northern areas of both islands. Conditions to persist overnight.

Monday: Variably cloudy and breezy conditions continue with brisk showers. Overall heavier rainfall to favor eastern areas.

Tuesday: Mostly sunny, warm, and breezy. Brisk showers are possible, favoring southern Trinidad.

Mostly clear skies east of Trinidad and Tobago on Thursday evening. (Weathernerds.org)

Marine: Seas are forecast to be agitated through the next five days due to a combination of increased low-level winds, King Tides, and long-period swells. In open waters, waves are forecast to be between 1.5 meters to 2.5 meters. Seas are forecast to be near and below 1.0 meter in sheltered areas.

Temperatures

On clear nights, radiative cooling can cause temperatures across Trinidad to dip below 20°C, which happens less than three to five days annually.
On clear nights, radiative cooling can cause temperatures across Trinidad to dip below 20°C, which happens less than three to five days annually.

On Friday morning, temperatures are forecast to be very cool across Trinidad and Tobago. Minimum lows across Trinidad are forecast to be generally between 19°C to 23°C while across Tobago, between 22°C to 24°C. Lower temperatures are possible across interior areas and valleys of Trinidad.

Temperatures are forecast to be cooler due to drier air moving into the region, allowing for mostly clear skies overnight into the morning period. Clear skies with light wind allow for heat at the surface to rise and cool in a process called radiative cooling.

However, by Saturday through the remainder of the forecast period, minimum lows across the country will be between 22°C to 25°C as fluctuating levels of cloudiness, and increased atmospheric moisture remain present.

On the other hand, maximum highs are forecast to be warmer, up to 32°C, on Friday across the country. Over the weekend and into next week, maximum temperatures are forecast to be between 30°C and 31°C due to increased cloud cover.

In urbanized areas like Port of Spain, Scarborough, San Fernando, and Chaguanas, the maximum temperatures could exceed 32.0°C.

Forecast Impacts

No significant rainfall or inclement weather impacts are anticipated through the next five days. Maximum daily rainfall accumulations are forecast to be less than 5 millimeters across the country and up to 10 millimeters possible, favoring eastern Trinidad in heavier showers. Higher rainfall totals are forecast on Sunday and Monday.

Gusty Winds

Low-level winds are forecast to remain elevated. Peak sustained surface winds are forecast on Sunday and Monday between 25 to 35 KM/H. Wind gusts up to 45 KM/H accompanying showers are likely, with gusts in excess of 50 KM/H possible, particularly across northern and eastern areas of the country.

With wind gusts in excess of 45 KM/H, whole trees are expected to be in motion, and there may be some inconvenience when walking against the wind gusts. Light outdoor objects may topple or become airborne such as garbage cans, potted plants, loose galvanize or construction material, and other outdoor furniture. Tents may jump. Older/weaker trees may fall, bringing down utility poles and lines.

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.

Isolated rainfall is forecast through the next five days.

Forecast - Isolated, Scattered, Widespread - What do they mean?

Forecast Discussion

A view of the Atlantic on Thursday 30th December 2021 at 7:30 PM.
A view of the Atlantic on Thursday 30th December 2021 at 7:30 PM.

Tropical Waves: There are no tropical waves in the Atlantic Basin.

A surface to low-level ridge is forecast to remain dominant through Friday, with a surge of dry air moving across the country. This dry and stable atmosphere will allow for cool overnight temperatures early Friday morning and on Friday night, with hot and sunny conditions during the day.

By Saturday morning, a surge of moisture accompanied by a surge of winds is forecast to begin moving across T&T associated with the high-pressure ridge flow. This moisture surge may fuel a few brisk showers, but increasing moisture and instability are forecast overnight due to a shearline approaching.

What is a shearline?
A narrow area along where there is an abrupt change in the horizontal direction of the wind. In the Northern Hemisphere, it is a line of maximum horizontal wind shear that occurs when easterly trades interact with winds with an enhanced northerly component that develops ahead of a cold front. It is common from late November through early May as cold fronts from North America descend into the Caribbean.

Shearlines tend to have strong low-level moisture convergence, which fuels shallow convection (showers). This setup is forecast to take shape across Trinidad and Tobago on Sunday through early Tuesday. Additionally, strong westerly wind shear will remain with overall higher rainfall limited to southern and eastern coastal areas.

A mostly dry and stable atmosphere is forecast to move in by early Tuesday, limiting cloudiness and shower chances across T&T, ushering the return of cooler than usual overnight temperatures.

Facebook Comments