The Department of Meteorology has issued a warm weather advisory for the Vavuniya, Mullaitivu, Trincomalee, Polonnaruwa, Batticaloa, Ampara and Monaragala districts.
The heat index is likely to rise to “Caution” level at some places in those seven districts during the daytime on Sunday (16), the department said.
What the index measures
The heat index is the temperature felt on the human body, and the department calculates its forecast using relative humidity together with the maximum temperature. It is a measure of perceived heat rather than of air temperature alone, so a moderate reading combined with high humidity can produce a higher index.
At Caution level, the department said, prolonged exposure to the sun and outdoor activity will result in fatigue, and continuing that activity could lead to heat cramps.
Residents in the affected districts have been asked to stay hydrated and to limit strenuous outdoor activities.
A second day of the same warning
The same seven districts were placed under a Caution-level heat index advisory for Friday daytime, in a warning issued during a dry spell that has affected more than 68,000 people across four districts.
The advisory covers the dry-zone districts of the north, east and south-east, and sits alongside a separate forecast of showers in Sabaragamuwa and four other districts in the wetter west and hill country.
National reservoir storage has fallen to 37% of capacity, and a Cabinet sub-committee is due to review the weather situation on Monday. The department has forecast that El Niño conditions will persist until next April.
A consultant paediatrician has separately warned that swings between heat and rain raise health risks for children, urging parents to keep them hydrated.
Update, August 17: conditions persist into a third day
Temperatures in parts of the same seven districts remain at cautionary levels, the Department of Meteorology said on Monday, NewsFirst reported — extending the warning across the weekend and into the new week with no change to the district list or the alert level.
A maximum temperature of 36.9°C was recorded at the Polonnaruwa meteorological station on Sunday. That figure is an air temperature reading taken at the station, and is not the same measure as the heat index the advisory is issued on; the index runs higher because it combines the maximum temperature with relative humidity.
The department repeated its advice that people working outdoors take adequate rest and drink enough water, and added a specific caution that the elderly and the sick should stay indoors.
Update, August 18: advisory extended to Wednesday and widened to the north
The Department of Meteorology issued a fresh warm weather advisory on Tuesday for Wednesday (19) daytime, Ada Derana reported. Daily Mirror said it was issued by the Natural Hazards Early Warning Centre at 4.00 p.m. on Tuesday.
The alert level is unchanged at “Caution”, but the area has widened. The new advisory covers the Eastern Province together with the Jaffna, Kilinochchi, Vavuniya, Mullaitivu, Polonnaruwa and Monaragala districts — adding Jaffna and Kilinochchi in the north to the districts named in the earlier warnings.
Both newsrooms list six named districts alongside the Eastern Province, though Daily Mirror’s headline refers to seven.
Daily Mirror reported that on the heat index scale, readings of 39–45°C constitute the “Caution” level, at which prolonged exposure and continued activity may cause fatigue and then heat cramps.
The department repeated its advice to stay hydrated, limit strenuous outdoor activity and take frequent breaks in shaded areas. It added that people working outdoors should wear lightweight, light-coloured clothing, that the public should check on elderly and sick people, and that motorists should never leave children unattended inside vehicles.
The advisory was issued in consultation with health authorities, and the public was advised to follow any further guidance from the Health Ministry’s Disaster Preparedness and Response Division.
