Sri Lanka is currently experiencing a complex and dynamic weather pattern, characterized by ongoing high temperatures, widespread thundershowers, and frequent severe lightning advisories. The nation is also preparing for the anticipated impact of El Niño, which is expected to significantly reduce rainfall during the upcoming Southwest Monsoon.
Persistent Heat Advisories and Health Precautions
The Department of Meteorology's Natural Disaster Early Warning Centre has consistently issued warm weather advisories. The Heat Index reached a ‘Caution Level’ across various parts of the island, with warnings issued for up to 21 districts between April 6 and April 17. An 'attention required' level heat warning was also in effect for April 19, covering areas in the Northern, North-Central, North-Western, Western, Sabaragamuwa, Eastern, and Southern provinces, along with the Monaragala district.
Director General of the Department of Meteorology, Athula Karunanayake, has stated that hot weather conditions are expected to persist until the end of May. The public is strongly urged to take action to minimize potential health impacts, with particular caution advised for small children, elderly individuals, and those with existing illnesses. Residents in affected areas are advised to be vigilant, rest in shaded areas, drink sufficient water, wear white or light-colored clothing, and limit strenuous activities to prevent fatigue and heat cramps.
Widespread Rainfall and Thundershower Forecasts
While warm conditions persisted, a significant shift towards wetter weather began on April 2. On April 1, a maximum temperature of 37°C was recorded in Kurunegala, and Kegalle received 39mm of rainfall.
Showers or thundershowers were consistently anticipated from April 6 to April 12, primarily in the evening after 1:00 PM or 2:00 PM, across various provinces and districts. Moderate to heavy rainfall, potentially exceeding 50 mm, was likely in the Western, Central, and Sabaragamuwa provinces, and the Kurunegala and Polonnaruwa districts, with some areas experiencing fairly heavy rainfall exceeding 75 mm. Heavy thundershowers observed on April 12 in the water catchment areas on the western slopes of the Central hills (Castlereagh, Maussakelle, and Upper Kotmale) between 3:00 PM and 4:00 PM, notably ending a nearly three-month dry spell that had impacted reservoir levels and drinking water supplies.
Subsequent forecasts included:
* April 13-17: Showers or thundershowers expected at most places across the island after 1:00 PM, with fairly heavy rainfall, exceeding 75 mm, likely in some areas of the Western, Sabaragamuwa, Central, Southern, and North-Western provinces on April 13. On April 14, Medawachchiya received the highest rainfall at 136.5 mm, with fairly heavy rainfall exceeding 50 mm in Western, Sabaragamuwa, Central, Galle, and Matara. Fairly heavy rainfall exceeding 50mm was also expected in various provinces from April 15-17.
* April 18-19: Showers or thundershowers expected in Western, Sabaragamuwa, Southern provinces, and Nuwara Eliya district after 1:00 PM on April 18, extending to Central, Uva, and North-Western provinces on April 19.
* April 20-21: Favorable atmospheric conditions for evening thundershowers across many parts of the island after 1:00 PM. Fairly heavy rainfall between 75 mm and 100 mm was forecast for Central, Sabaragamuwa, Western, North-Central, and Southern provinces on April 20, with heavy rainfall exceeding 100 mm anticipated on April 21 in Western, Sabaragamuwa, Central, North Western provinces, and Galle, Matara, and Anuradhapura districts.
* April 22-24: Moderately heavy rains exceeding 75 mm were forecast for Western, Sabaragamuwa, Central, Uva, Southern provinces, and Ampara, Kurunegala, Batticaloa districts on April 22, and similar areas including Anuradhapura on April 23. Widespread showers with fairly heavy falls exceeding 75 mm were anticipated on April 24 in Western, Sabaragamuwa, Central, North-Western, and Southern provinces.
* April 25: Rain or thundershowers expected after 1:00 PM in Western, Sabaragamuwa, North-Western provinces, and Galle, Matara, Kandy, and Nuwara Eliya districts. Showers also occurred in sea areas from Puttalam to Pottuvil.
Recent and Upcoming Rainfall Forecasts (April 26 - May 2)
* April 26: Showers or thundershowers forecast after 2:00 PM in Western, Sabaragamuwa, North-Western provinces, and Galle, Matara, Kandy, Nuwara Eliya, and Puttalam districts. Morning rain was anticipated in the Northern and some Southern province areas.
* April 27: Widespread showers or thundershowers expected after 1:00 PM, with morning rain in some Southern province areas. Moderate heavy rain, exceeding 75mm, was highly probable in Western, Sabaragamuwa, Central, Southern, Uva, North Central provinces, and Kurunegala district.
* April 28: Widespread showers or thundershowers forecast for most parts of the island after 1:00 PM. Morning rain was anticipated in some Southern province areas and Ampara district. Fairly heavy rainfall, exceeding 75mm, was highly probable in Western, Sabaragamuwa, Central, Northwestern, North-Central, Southern provinces, and Mannar district.
* April 29: Widespread showers or thundershowers anticipated after 1:00 p.m., with morning rain in parts of the Southern Province. Fairly heavy rainfall exceeding 50mm was expected in Sabaragamuwa, Northern, North-Central, Central provinces, and Trincomalee and Kurunegala districts.
* April 30: Widespread showers or thundershowers anticipated after 1:00 p.m., with morning rain possible in some areas of the Southern Province and Kalutara district. Fairly heavy rainfall exceeding 50mm was likely in isolated areas within the Sabaragamuwa, Central, North-Central provinces, and Trincomalee district.
* May 1: Widespread showers or thundershowers expected in most parts of the island after 1:00 p.m. Fairly heavy rainfall exceeding 50mm was likely in Sabaragamuwa, Central, North-Central provinces, and Trincomalee district. Showers also occurred in some parts of the Southern Province and Kalutara district during the morning.
* May 2: Widespread showers or thundershowers are anticipated in many parts of the island after 1:00 p.m. in the Western, Sabaragamuwa, Central, Uva, Eastern, and North-Central provinces, including the Polonnaruwa, Galle, and Matara districts. Morning rain is possible in the Southern Province, Kalutara and Colombo districts, and coastal areas.
Severe Lightning Advisories
The Department of Meteorology has issued multiple severe lightning advisories, urging the public to take precautions against temporary strong winds and lightning during thundershowers.
* From April 2 to April 12, 'Amber' and 'Red' alerts for severe lightning were in effect across numerous districts.
* From April 13-17, 'Amber' advisories were consistently issued, with Red alerts for 14 districts on April 15 and 13 districts on April 16, and 7 districts on April 17.
* From April 19-25, 'Amber' advisories were frequently issued, with a Red alert for severe lightning issued for all provinces of Sri Lanka on April 20.
* April 26: A specific warning for severe lightning was issued for the Western and Sabaragamuwa provinces, and the Galle, Matara, Kandy, Nuwara-Eliya, and Kurunegala districts.
* April 27: A detailed advisory for severe lightning included Red alerts for 16 districts and Amber alerts for 9 districts, covering Western, Sabaragamuwa, Central, North-Central, Northwestern provinces, and Galle, Matara, Kandy, Mannar, and Vavuniya districts.
* April 28: An 'Amber' advisory for severe lightning was issued, covering the Western, Sabaragamuwa, Central, Uva, Northern, North-Central, Southern, and North-Western provinces, as well as the Trincomalee district.
* April 29: A warning/advisory for severe lightning was re-issued, covering the Western, Sabaragamuwa, Central, Northern, North-Central, Southern, North-Western, and Uva provinces, and the Trincomalee district.
* May 1: An 'Amber' advisory for severe lightning was issued, covering the Sabaragamuwa, Central, Uva, and North-Central provinces, along with the Vavuniya, Mullaittivu, Kilinochchi, Mannar, Kurunegala, and Trincomalee districts.
* May 2: The Department of Meteorology has issued an 'Amber' advisory for severe lightning, valid until 11:30 p.m. This advisory covers the Northern, North-Central, Central, Sabaragamuwa, Eastern, Uva, Western, North-Western, and Southern provinces, along with the Anuradhapura district. Thundershowers with severe lightning and temporary localized strong winds are highly likely in these areas after 1:00 p.m.
During lightning and thunder, the public is strongly urged to avoid staying outdoors or under trees, and instead seek shelter in a safe building or a closed vehicle. Open areas such as paddy fields, tea estates, sports grounds, and reservoirs should also be avoided, as temporary strong winds may occur during thundershowers. The public is advised to take necessary precautions to minimize lightning-related accidents and to seek assistance from regional disaster management officers in case of an emergency.
Misty Conditions
Early morning mist or fog has been anticipated in various parts of the island throughout April and into May. For April 26, misty conditions were anticipated in the Central, Sabaragamuwa, Uva, Northcentral, Galle, Matara, Kalutara, and Kurunegala districts. On April 27-28, misty conditions were expected in parts of the Central, Sabaragamuwa, and Uva provinces, along with the Anuradhapura and Kurunegala districts. For April 29-30, misty conditions were expected in parts of the Central, Sabaragamuwa, North-Central, and Uva provinces, along with the Kurunegala district. On May 1-2, misty conditions were anticipated in parts of the Central, Sabaragamuwa, North-Central, and Uva provinces, along with the Ampara and Polonnaruwa districts.
Sun Directly Overhead Phenomenon
The sun's apparent northward relative motion meant it was directly overhead Sri Lankan latitudes from April 5 to April 15. This phenomenon concluded on April 15, around 12:10 noon, when the sun was directly overhead Pandatharippu, Thellippalai, Varuthaleivilan, Vasavilan, and Manatkaadu.
Meteorological Outlook and Recent Observations
The Director General of the Department of Meteorology predicts that Sri Lanka will receive its usual rainfall by May or June. However, a decrease in rainfall of more 30% is anticipated during the upcoming Southwest Monsoon, a period noted as the beginning of El Niño in May.