Media Center
Climate Bulletin for Sri Lanka (Week of 21 – 28 March 2025)
Highlights
Rainfall Prediction: During the next week (March 19th–25th), moderate rainfall (25–50 mm) is predicted for the Central, Uva, Southern, Eastern, Northern, North- Western, Sabaragamuwa, and North-Central provinces while light to moderate rainfall is predicted for the Western province.
Monitored Rainfall: During the last 8 days (13 Mar – 19 Mar), SL received an average of 3.5mm/day of rainfall, while in the hydro catchments, the average rainfall was 121.3 mm/day. Highest daily rainfall was in Katunayake on 19th March (43.2mm).
Monitored Sea and Land Temperature: Average maximum land surface temperature was 31.7°C in the last week with cooler anomalies from seasonal average of 1°C. The Northern plains were the warmest, followed by the Western and Southern plains. Sea surface temperature around Sri Lanka was 1.0°C above average from 11 -17 Mar 2025.
Interpretation
Monitoring
Rainfall: Average Rainfall in the Met Stations for the previous week of (13 Mar – 19 Mar) = 3.5 mm/day. Maximum Daily Rainfall: 43.2 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: Easterly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were below normal ( cooler anomalies) in some parts of Sri Lanka, including the Northern, North-Central, and North-Western Provinces, while remaining normal in other parts of the country from March 9 to 15.
Rainfall: During the next week (March 19th–25th), moderate rainfall (25–50 mm) is predicted for the Central, Uva, Southern, Eastern, Northern, North-Western, Sabaragamuwa, and North-Central provinces while light to moderate rainfall is predicted for the Western province.
Temperatures: The temperature will remain above normal in some parts of the Northern and North-Western Provinces from March 24 to 28 and will remain normal in other parts of Sri Lanka from March 18 to 28.
Teleconnections: The MJO will slightly enhance rainfall from March 18 to 22, moderately suppress rainfall from March 23 to 27, and significantly suppress it from March 28 to April 02.
Seasonal Precipitation: The precipitation forecast for the April-May-June, 2025 season shows a 90% or more tendency toward normal precipitation for the Northern half of the country, while it shows a 90% or more tendency toward normal precipitation for the Southern half of the country.
Terminology for Rainfall Ranges
| Terminology | Rainfall (mm/week) |
| Light Showers | Less than 12.5 mm |
| Light to Moderate | Between 12.5 mm and 25 mm |
| Moderate | Between 25 mm and 50 mm |
| Fairly Heavy | Between 50 mm and 100 mm |
| Heavy | Between 100 mm and 150 mm |
| Very Heavy | More than 150 mm |
