Trinidad and Tobago woke up to unusually cool temperatures on Monday morning as an area of dry, cool air settled in across the region. At the Piarco International Airport, where climate records have been recorded since the mid-1900s in Trinidad, temperatures bottomed out at 18.3°C, the lowest since 2012, according to the Trinidad and Tobago Meteorological Service.
Across many interior, southern and eastern areas of Trinidad, where official automated weather stations are not located, many used free-standing, mercury or alcohol thermometers to record the unusually chilly air outdoors. Several submitted pictures of temperatures between 12.0°C and 16.0°C on thermometers, but these measurements are not necessarily reliable.
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.
January 30th 2023, Temperatures
The coolest temperatures were recorded across interior areas of central and southern Trinidad, where light winds, clear skies, and dry air allowed for favorable cooling near the surface.
Automated weather stations recorded temperatures as low as 17.90°C in Bonne Aventure, South Trinidad, 17.30°C at Chickland, Central Trinidad, 18.30°C at Piarco, North Trinidad, and 21.00°C at Crown Point, Tobago.
Less reliable and accurate thermometer recordings from interior areas of central, southern, and eastern Trinidad measured temperatures as low as 12.5°C in Valencia, East Trinidad. However, cooler temperatures than those recorded by automated weather stations, particularly in interior areas of Trinidad and valleys, are plausible given the optimal conditions on January 30th, 2023.
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.
Forecast Into This Week
For tonight, generally, dry conditions are expected to persist, with some cloud cover expected. This would result in temperatures in the upper teens (18°C to 20°C) across interior areas of Trinidad, slightly warmer than last night, 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.
