• Absence of clouds, direct solar radiation, unpredictable winds: Met. Dept.
• 3-4 degrees Celsius above normal temperature in certain areas

While the prevailing heat is a deviation from the average temperature, the warmer conditions are likely to subside after a month following sufficient inter-monsoonal rainfall, the Department of Meteorology reveals.

Speaking to The Sunday Morning, Department of Meteorology Director (Weather Forecasting and Decision Support) A.L.K. Wijemannage said: “This heat is likely to last until about March, after which we expect to receive a considerable amount of rain in April. Even throughout March, the heat won’t be continuous but will fluctuate since it will reduce with the coming rains.”

According to Wijemannage, the prevailing heat has been caused by the lack of cloud formation, which means that solar radiation strikes the ground directly, leading to increased heat. There is also a variable wind which blows with no definite direction and without strength, leading to increased discomfort for people. 

Explaining that the prevailing conditions did not constitute a heatwave but a minor increase in temperature, he however acknowledged that this was somewhat of a departure from the average expected temperature for the period: “Certain areas have an increase of about 3-4 degrees Celsius above the normal temperature.”

“The North Western Province, Gampaha, Colombo, Anuradhapura, Polonnaruwa, and Trincomalee are the areas most affected, but almost all other areas are also experiencing higher than average temperatures of at least 2 degrees Celsius. Compared to previous years, this increase is not typical for February.”

The areas prone to higher temperatures are experiencing a notable impact at present. “In areas such as Kurunegala and Ratnapura, the maximum temperature has gone up to about 37 degrees Celsius, which is a somewhat high value. The average for these areas should be around 33 degrees Celsius. In this respect, this is a considerable increase unlike in previous years. However, this is not to say that there haven’t been years when the temperature hasn’t risen higher to about 39-40 degrees Celsius.”

Wijemannage noted that the department was expecting the prevailing conditions to change with the inter-monsoon commencing around mid-March. However, based on regional forecasts, meteorologists are also expecting reduced rain for the upcoming two months for the region. 

He described the present weather as a local effect due to the reduction in rains. “We are at the tail-end of the northeast monsoon, which will be followed by the inter-monsoon. We are expecting less-than-average rainfall for the inter-monsoon period for the South Asian region,” he said, stressing that while it would not lead to a drought situation, minor crops could be affected. 

Together with the Health Ministry, the department advises the public to take precautions against dehydration, especially those who undertake outdoor activities between 10 a.m. to 4 p.m., when the heat is at its peak.

Moreover, the elderly and those with certain illnesses susceptible to intense heat should avoid being outdoors as much as possible and in general wear lightweight or light-coloured clothing while being adequately protected against the sun while outside. 

Issuing a warning for Friday (23), the department’s Natural Hazards Early Warning Centre noted that the Heat Index – the temperature felt on the human body – was expected to increase up to the ‘Caution’ level in some places in the North Western and North Central Provinces and in the Gampaha, Colombo, Hambantota, and Trincomalee Districts. 

This warning was removed for yesterday (24) given the drop in temperature, although the heat would not entirely dissipate, as Wijemannage noted. 

According to the Meteorology Department, temperature at 39-45 degrees Celsius is considered ‘Caution’ level, leading to possible fatigue with prolonged exposure and activity and the likelihood of heat cramps with continuing activity.