Weather Forecast (Next 48 Hours)
As of 10:00 AM Sunday 11th August 2019, mostly sunny to partly cloudy skies are occurring across Trinidad and Tobago. Isolated showers are ongoing across the Southern half of Trinidad. Heavier showers and possible thunderstorms are possible by the late afternoon, favoring Western Trinidad.
Periods of showers and isolated thunderstorms are forecast on Monday, with the latter half of Tropical Wave 34 affecting the region.
Hot temperatures are ongoing across Trinidad and Tobago on Sunday.
Throughout the morning, mostly settled conditions occurred across Trinidad and Tobago with a few brisk isolated showers favoring the southern half of Trinidad. Partly cloudy skies are forecast to continue through the late morning and afternoon with isolated to scattered showers developing mainly across Trinidad. Heavier showers and thunderstorms may develop across the Western half of the islands, as well as south-facing slopes of the Northern Range.
Showers are forecast to subside by the late evening, giving way to mostly to partly cloudy skies, barring the odd isolated shower. Isolated showers are forecast to persist overnight, interrupting mostly settled conditions. An increase in showers are forecast by the early morning tomorrow, with a few thunderstorms. Again, most of this activity is forecast to favor Trinidad.
Generally gentle to fresh breezes (15-40 KM/H) winds are forecast for Sunday into Monday mainly from the east to southeast.
What We Expect
Winds, at low levels, are becoming more southerly to southeasterly, compared to the predominantly easterly winds.
Favorable upper-level conditions and increased low-level moisture are in place as the ITCZ and this tropical wave moves across the Windwards.
This activity, combined with local climatic features such as daytime heating, an overall light wind regime, and sea breeze convergence is forecast to trigger locally heavy showers and thunderstorms across and near Trinidad and Tobago over the next 24 to 48 hours.
Increasing cloudiness is forecast to lead to periods of showers and thunderstorms across Trinidad and Tobago as the day progresses, interrupting sunny skies. This activity is due to a tropical wave moving across the region.
On Monday, partly cloudy skies are forecast to persist throughout the day, with intermittent showers across the islands. Isolated heavier showers and thunderstorms are forecast to favor the late morning through the late afternoon, mainly across Trinidad. Conditions are forecast to become mostly settled by the night, with a few lingering showers.
Street/flash flooding, gusty winds, and landslides are possible, particularly across Northern and Western Trinidad.
Based on the latest model guidance, isolated to scattered showers and isolated thunderstorms are forecast to move across both islands, with heavier activity favoring much of Trinidad over the next 24-48 hours.
Locally Heavy Rainfall & Flooding: Based on the latest model runs on Sunday morning, from Sunday morning (2:00 AM) through Tuesday (2:00 PM), generally, over the 48hour period, models are in agreement of fewer than 15 millimeters across of Trinidad and Tobago and between 20-40 millimeters across isolated areas of Trinidad and up to 50 millimeters across Eastern Trinidad.
Generally, with heavy showers and thunderstorm activity, street flooding, particularly in flood-prone areas or areas with poor drainage, is possible as well as flash flooding in areas where more prolonged heavy rainfall may occur, based on the above-mentioned forecast rainfall totals associated with the ITCZ as it moves across the area over the next 24-48 hours.
Frequent Lightning: In addition, with thunderstorms, frequent lightning is likely.
Gusty Winds: Gusty winds, generally between 40 and 60 KM/H are possible Gusty winds are most likely prior to, in the vicinity of, or occur during heavy showers or thunderstorms. With wind gusts up to 60 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.
Landslides: Heavy showers across the Northern Range may trigger landslides in landslide-prone areas. Particularly in areas that receive heavy rainfall, landslides and/or mudflows may occur across both islands. These landslides, in addition to gusty winds, may down trees, utility poles and impede traffic on roadways.
Last night’s minimum temperatures were warm at 24.3°C at Piarco, Trinidad and 27.2°C at Crown Point, Tobago. Minimum low temperatures across Trinidad and Tobago tomorrow are forecast to range between 24°C-27°C, with temperatures at the upper end of the minimum low-temperature range favoring Tobago.
Today, maximum high temperatures across T&T are forecast to be near a hot 33°C at Piarco, Trinidad and a heat index of ranging from 35°C to 45°C . Across Tobago, maximum high temperatures are forecast to be a warm 32°C with a heat index of 34-37°C. The heat index is an index that combines air temperature and relative humidity, generating a “feel’s like” temperature.
The Heat Index
Several persons across the country took to social media to complain about the heat, or more so what outside felt like. This is called the heat index and is a combination of air temperature and relative humidity determining what the air feels like to a person i.e. how hot it actually feels.
The heat index is important because of sweating. Your body sweats in order to cool the skin and maintain a constant, healthy body temperature. This cooling process means that the sweat has to evaporate off the skin to remove heat. However, if the sweat is unable to evaporate, the body isn’t able to regulate temperature.
With high volumes of moisture in the air, also known as high relative humidity, which T&T regularly experience due to its tropical climate, the rate of sweat evaporation decreased. This is because the atmosphere is unable, or has limited potential to hold additional moisture in the atmosphere.
This results in you feeling warmer in humid conditions and cooler in less humid conditions i.e. when relative humidity decreases. As temperature increases, the heat index increases. As relative humidity increases, so does the heat index.
The heat index is generally classified into four categories: caution, extreme caution, dangerous and extremely dangerous. Generally across Trinidad and Tobago, we experience heat indices of caution to extreme caution in times of hot days, with isolated areas experiencing dangerous heat indices such as urban areas.
Today, heat index levels are between extreme cautious to dangerous levels. Heat cramps and heat exhaustion are likely. Heatstroke may be probable with continued outdoor activity.
Is this a heatwave?
Seas are forecast to remain slight to moderate in open waters throughout the weekend. Waves in open waters are forecast to remain between 1.0 to 1.5 meters particularly East of Trinidad and Tobago through Sunday. In sheltered areas, seas are forecast to remain near calm. Winds will be from the east to southeast through the next 2 days at 10-15 knots.