Weather Forecast (Next 24 Hours)
As of 7:30 AM Wednesday 21st August 2019, mostly sunny to partly cloudy skies are occurring across Trinidad and Tobago. Isolated showers are possible later this afternoon, across the Western half of Trinidad, with a few, brisk isolated showers forecast to affect the Eastern Coastal areas of T&T through the evening, interrupting sunny skies. A settled and mostly clear night is ahead.
Very hot temperatures are forecast across Trinidad and Tobago, with an elevated concentration in Saharan Dust.
Throughout the morning, mostly settled conditions are forecast across Trinidad and Tobago. Partly cloudy skies are forecast to continue through the afternoon and evening across the Eastern halves of T&T, with the odd isolated shower due to low-level cloud patches traversing both islands.
Across the Western half of Trinidad, partly cloudy skies may give way to a few isolated showers, favoring coastal areas. A heavier shower or thunderstorm may favor southwestern Trinidad. This is due to very weak winds allowing daytime heating and sea breeze convergence to dominate.
Note that in heavier showers or a thunderstorm, locally heavy rain and gusty winds can trigger street flooding and down trees or utility poles.
On a much broader scale, a high-pressure system is dominating the Lesser Antilles, producing sunny skies across the region. However, Tropical Wave 37, which originated as a mid-latitude trough, has weakened the wind regime across the region, allowing increased chances for afternoon showers and thunderstorms due to decreased winds. This tropical wave is fairly weak with much of the showers associated with the wave remaining north of T&T (north of 15N).
Generally gentle to fresh breezes (15-40 KM/H) winds are forecast for Wednesday through the week, mainly from the east. A slight increase in winds is forecast on Friday.
Last night’s minimum temperatures were warm at 23.9°C at Piarco, Trinidad and 25.6°C at Crown Point, Tobago. Minimum low temperatures across Trinidad and Tobago tomorrow are forecast to range between 24°C-26°C, with temperatures at the upper end of the minimum low-temperature range favoring Tobago. Low temperatures are likely to be lower across inland and mountainous areas. Light winds and clear skies will allow for a cool night.
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?
An article from the Pan American Health Organization (PAHO) earlier last month made the rounds on social media, urging Northern Hemisphere countries to prepare for heatwaves.
Today (and tomorrow) are just some hot days in the tropics, as heatwaves are generally prolonged heat with life-threateningly high temperatures.
Seas are forecast to remain slight in open waters throughout the weekend. Waves in open waters are forecast to remain up to 1.0 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 through the next 3 days at 10-15 knots.