Over the course of the week, the heat has been building across Trinidad and Tobago. Thursday’s maximum high temperatures across Trinidad were generally between 33.0°C and 34.0°C, and 31.0°C and 32.0°C across Tobago. In urban areas and areas where development is prevalent, temperatures soared above 34.0°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
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.
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.
Forecast Temperatures & Heat Indices
Last night’s minimum temperatures were 25°C at Piarco, Trinidad, and 26°C at Crown Point, Tobago. Tonight’s minimum temperatures are forecast to be near 25°C at Piarco, Trinidad, and 27°C at Crown Point, Tobago.
Today’s maximum high temperatures across T&T are forecast to be near 34°C at Piarco, Trinidad and 32°C at Crown Point, Tobago. Similar temperatures are likely through the next three days, with maximum high temperatures forecast to be near 34°C at Piarco, Trinidad, and 32°C at Crown Point, Tobago.
High heat indices are forecast across Trinidad and Tobago. Across most of Trinidad, maximum heat indices are forecast to range between 38.0°C and 42.0°C, with indices at the upper end of the range, particularly in urban areas. In Tobago, slightly lower heat indices are forecast, between 34.0°C and 36.0°C.
Note that heat indices above 41.0°C are considered dangerous. At this heat index level, heat cramp and heat exhaustion are likely. Heat stroke becomes probably with strenuous outdoor activity.
With Saharan Dust remaining across the area, sensitive groups such as children, the elderly and persons with respiratory ailments are advised to take the necessary precautions.
As stated in an interview with Trinidad and Tobago Newsday, climatologist Kaidar Kissoon with the Trinidad and Tobago Meteorological Service stated that for the remainder of April and into May the sun will be at this country’s latitude of 10.5 degrees north.
“We are going into a hotter period with the atmosphere warmer, hotter temperatures and more intense sunlight with no cloud cover as compared to a December or January. It will be warm and the sun stinging on a clear day. You will it find extremely hot.”Kaidar Kissoon, Climatologist, Trinidad and Tobago Meteorological Service
Trinidad and Tobago Newsday
At Atlantic high-pressure system, fairly weaker low-level wind speeds across the region and a subsident pattern is forecast to limit shower activity and maintain hot, sunny and dry conditions across the islands.