Over the next four days, the weather across T&T is forecast to be generally stable with drier than usual air and a surface to mid-level ridge moving in across the region. However, with sunny skies over the next 4 days, the heat is on.
Note that highly localized showers are still possible, mainly during the afternoon and favoring Western and Northern Trinidad, particularly on Sunday with the odd thunderstorm. Activity forecast to remain brief.
There are no alerts, watches, or warnings from the Trinidad and Tobago Meteorological Service at this time.
The Forecast (Through Wednesday)
Forecast: Mostly hot and sunny days remain in the forecast through Wednesday, becoming partly cloudy by the late morning through the afternoon. Mainly on Sunday, during the late morning through the afternoon, isolated showers and the odd thunderstorm may interrupt sunny partly cloudy skies, favoring western coastal Trinidad. Conditions are forecast to remain hot and sunny elsewhere into the evening. Mostly clear and relatively cool nights are forecast.
Hazards: With mostly settled conditions, maximum high temperatures and heat indices will be the main hazard so particularly between 9:00 AM and 3:00 PM, stay cool and hydrated! With sunny skies, the UV Index will also be very high to extreme so wear sunscreen and eye protection when heading outdoors! In the event of an isolated, heavy downpour or thunderstorm during the afternoon, the main hazards include localized heavy rainfall, which may reduce visibility and gusty winds in downburst-like fashion, up to and in excess of 50 KM/H. Street or flash flooding is possible, along with frequent lightning. As light winds and sufficient moisture will be in place only on Sunday, funnel clouds are also possible, with brief spin up activity into a short-lived tornado, though these chances are very low.
Overview: A deep-layered low-pressure system is north of the Lesser Antilles, with high chances of tropical cyclone formation as of Sunday morning. Regardless of formation, this system will maintain a weak pressure gradient across the region through mid-week, even with a surface to mid-level high-pressure system in place. This will result in light winds to near calm conditions, allowing daytime heating and sea breeze convergence to trigger isolated showers along western coastal Trinidad mainly after midday.
However, the surface to mid-level environment will become notably drier from Sunday night through Wednesday night, limiting the localized afternoon showers and thunderstorms through the first half of the week. By Thursday through Friday, a surge in trade winds in conjunction with an increase in moisture associated with a tropical wave will have a very wet end to the week, particularly Friday through the weekend.
Across both islands, hot conditions are forecast over the next 4 days. The maximum high for Trinidad is forecast to be near 34.0°C, up to 37.0°C in urban and built-up areas, particularly between 9:00 AM and 3:00 PM. In Tobago, the maximum high is forecast to be near 33.0°C.
Temperatures in cities, such as Port of Spain, tend to be much higher than surrounding locations due to a phenomenon called the Urban Heat Island Effect. There are several causes, but the main instigator for this phenomenon tends to be increased dark surfaces such as roads and pavement in cities, which absorb solar radiation more than surrounding areas.
The Heat Index
The heat index will be between levels that require extreme caution to near dangerous levels through Wednesday across Trinidad and Tobago. 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.
Across Trinidad, the maximum heat index is forecast to be between 35°C and 45°C and even higher in urbanized areas. In Tobago, the maximum heat index is forecast to be between 35°C and 42°C.
The heat index is important because of sweating. Your body sweats 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.
Heat index is generally classified into four categories: caution, extreme caution, dangerous, and extremely dangerous.
Sustained surface winds will be light to near calm through Wednesday. In thunderstorm activity, gusts up to and in excess of 50 KM/H are possible.
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.
Across most areas of Trinidad and Tobago, little to no rainfall is anticipated over the next 4 days, with maximum accumulation totals near 5 millimeters. In areas where isolated heavy showers or thunderstorms occur, accumulations up to 25 millimeters are possible.
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: Frequent lightning is possible in thunderstorm activity. Lightning can cause power outages, voltage dips, damage to life and property, particularly during cloud-to-ground lightning strikes.
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.
Highly isolated rainfall is forecast on Sunday, with very hot and sunny conditions persisting through Wednesday.