As of 12:30 PM Sunday 8th September 2019, sunny to partly cloudy skies are ongoing across Trinidad and Tobago with very hot conditions persisting.
Brief, isolated showers and the odd thunderstorm are forecast across Western Coastal Trinidad and the western half of Northern Trinidad, which may become heavy or thundery across southwestern and northwestern Trinidad. Street flooding and gusty winds may accompany these heavier or thundery showers.
Mostly settled conditions are forecast by the evening into Monday.
An approaching Tropical Wave is forecast to move across the Islands on Monday, bringing isolated showers and thunderstorms.
There are NO alerts, watches or warnings in effect for Trinidad and Tobago from the Trinidad and Tobago Meteorological Service at this time.
Last night’s minimum temperatures were warm at 24°C at Piarco, Trinidad, and 26°C at Crown Point, Tobago. Minimum low temperatures across Trinidad and Tobago tomorrow are forecast to range between 25°C-27°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.
Today, maximum high temperatures across T&T are forecast to be near a hot 34°C at Piarco, Trinidad and a heat index ranging from 38°C to dangerous 50°C. Across Tobago, maximum high temperatures are forecast to be a warm 32°C with a heat index of 34-38°C. The heat index is an index that combines air temperature and relative humidity, generating a “feel’s like” temperature.
The Heat Index
The heat index 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 likely to remain at extreme cautious to dangerous levels. Heat cramps and heat exhaustion are likely with heatstroke probable with continued activity.
Seas are forecast to be slight to moderate with waves up to 1.5 meters in open waters and near calm in sheltered areas.
Over the Next 24-36 Hours
Weather: Though hot and sunny conditions will prevail across Trinidad and Tobago on Sunday. The approaching Tropical Wave 45 is forecast to move across the islands on Monday into Tuesday.
Showers are forecast to remain isolated to scattered with a few thunderstorms favoring Trinidad. These showers will interrupt partly cloudy to cloudy periods, so don’t expect constant rain throughout the day, but keep the umbrella close by if you’re heading out.
Based on present model guidance, and satellite appearance, this tropical wave is fairly weak. Some scattered showers are likely with model guidance indicating that a dry and stable mid to upper level will negate any significant deep convective activity. Activity will mostly subside by the late evening, but a few isolated showers may occur throughout the night, favoring the eastern halves of T&T.
Winds: Sustained surface winds between 15 KM/H and 30 KM/H with gusts in excess of 50 KM/H are possible in heavy showers or thunderstorms across Trinidad and Tobago.
With wind gusts in excess of 50 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.
Rainfall: No significant accumulation is forecast across T&T. In isolated downpours across West Trinidad, up to 20 mm possible with thunderstorms and downpours, totals up to 50 millimeters are possible in highly localized areas.
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.
Frequent Lightning: In addition, with forecast thunderstorms, frequent lightning is likely.
Why I May Not/Will Not See Constant 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.
Today, very isolated activity is forecast. On Monday, isolated to scattered showers and isolated thunderstorms are forecast.
There will be an update on Invest 94L later this evening, after the 2PM National Hurricane Center’s update and the 12Z model runs. Note that this system has a medium chance of development, and there is some likelihood of T&T being affected, though as of present, only as a strong tropical wave. This system is 5-6 days away, as it slowly moves toward the Lesser Antilles.