Minimum temperatures across many areas of Trinidad and Tobago continue to remain below 20.0°C on Tuesday morning for the second consecutive day as an area of dry, cool air settled in across the region.
Though Tuesday morning’s temperatures were not as low as Monday, at the Piarco International Airport, Trinidad’s climate reference site, the minimum low bottomed out at 18.6°C.
How cold did it get?
Monday morning was the coolest morning at the Piarco International Airport since 2012, according to the Trinidad and Tobago Meteorological Service.
Automated weather stations recorded temperatures as low as 17.9°C in Bonne Aventure, South Trinidad, 17.3°C at Chickland, Central Trinidad, 18.3°C at Piarco, North Trinidad, and 21.0°C at Crown Point, Tobago.
Tuesday morning’s minimum temperatures were marginally warmer than Monday, with the minimum low at the Piarco International Airport just 0.3°C warmer than 24 hours prior, coming in at 18.6°C. In Tobago, Tuesday’s temperatures were cooler than Monday’s, coming in at 20.6°C at the A.N.R. Robinson International Airport, Crown Point, Tobago.
Notable minimum low temperatures on Tuesday also came in at Penal from a Trinidad and Tobago Meteorological Service-owned automated weather station at 17.42°C, as well as in Bonne Aventure and Chickland, Freeport from personal automated weather stations at 17.6°C and 17.7°C respectively.
For another day, unofficial and lesser reliable temperature reports from interior areas of Trinidad that lack automated weather stations recorded much lower than usual temperatures, far from the official numbers at Piarco. These handheld or wall thermometers measured temperatures as low as 12.5°C in Valencia on Monday and 13°C in Valencia and Sangre Grande on Tuesday, gaining social media prominence.
While cooler temperatures below 18°C are plausible, particularly in interior areas of Trinidad and in valleys, these measurements will not stand up to the scrutiny required for reliable ambient temperature measurements used for official records.
How to reliably measure outdoor temperatures?
To measure outdoor air temperature on land, a thermometer is placed inside an enclosure such as the common wooden box-shaped Cotton Region Shelter. There’s also the more modern Maximum-Minimum Temperature System (MMTS), which is often used for U.S. official air temperature measurements and looks more like a beehive. Regardless of the shape, the enclosure is white in color to reflect solar radiation, which heats the thermometer and keeps it from getting an accurate air temperature reading. The enclosure also typically has slatted sides to allow airflow and a double roof (a roof and a raised roof over that) to protect the thermometer from rain and further resist the influence of the Sun.
The bottom of the enclosure is situated between 1.2 and 2 meters (4.1 to 6.5 feet) above the ground, which should be grass or dirt (if it’s grass, it should be kept short). The area around the enclosure should be free of trees, and preferably there should be a good view of the horizon. The enclosure should be kept away from buildings and pavement, which capture heat from the Sun throughout the day and can make the thermometer artificially warm. All this is meant to ensure that the thermometer gets the true temperature with unobstructed airflow and without interference from radiating heat.
Why has it been so cold?
Cool Temperatures Across T&T Due To North American Air Mass
Is this record-breaking?
According to the Trinidad and Tobago Meteorological Service, the 18.3°C minimum low temperature on January 30th, 2023, was the coolest minimum low recorded at Piarco since 2012. However, the TTMS has recorded even lower temperatures in the past. The lowest minimum temperature on record at Piarco is 16.1°C, which occurred on the nights of January 21st and 30th, 1964, followed by 16.4°C on the night of January 28th, 1976.
Temperature records elsewhere, like Penal, Brasso, Caroni, and El Reposo in Sangre Grande, where both automated weather stations exist, and cooler temperatures than Piarco are usually recorded, have not been recorded as long as Piarco.
For T&T, the climate reference site for Trinidad is Piarco, where records have been kept since 1946, and Crown Point for Tobago, where records have been kept since 1969.
The 1991-2020 average minimum low temperature for January is 22°C at Piarco and 23°C at Crown Point, meaning the last two days have been well below average for this time of year. According to the Trinidad and Tobago Meteorological Service, “There is a high probability that cool nights will continue into the first week of February and possibly drop lower than
18.3°C. Therefore, individuals who are susceptible to low temperatures and who experience respiratory ailments must be proactive at this time and wear warm and/or extra clothing, especially during this coming week.”
Forecast Into This Week
For tonight, generally, dry conditions are expected to persist, though an increase in moisture and cloud cover is expected. This would result in temperatures still remaining in the upper teens (18°C to 20°C) across interior areas of Trinidad, continuing to trend slightly warmer than the last two nights, and lows near or at 21°C across Tobago.
By Wednesday afternoon (February 1st), a low-level trough is forecast to move across the southern Windwards and Trinidad and Tobago, marginally increasing moisture levels and resulting in slightly warmer nighttime temperatures through the end of the week. Warmer daytime temperatures are also forecast as this trough brings near calm to light winds during the day on Wednesday, with wind speeds picking up again from Thursday.
