Media Center
Climate Bulletin for Sri Lanka (Week of 11- 18 April 2025)
Highlights
Rainfall Prediction: During the next week (April 9–15), “fairly heavy” rainfall (50–100 mm) is predicted for the Western Province, while “moderate” rainfall (25–50 mm) is expected in the Sabaragamuwa, Uva, Central, Eastern, North-Central, Southern, and North-Western Provinces. “Light showers” are expected in the Northern Province.
Monitored Rainfall: During the last 8 days (02 – 09 April), Sri Lanka received an average rainfall of 9.6 mm per day, while the hydro catchment areas recorded an average of 15.4 mm per day. Highest daily rainfall was in Galle on 04th April (79.8 mm).
Monitored and Predicted Wind: From 01- 07 April, winds at 850 mb (1.5 km) from the Northeast reached to 2 m/s. From April 10 to April 16, winds are predicted to come from the south-west, with wind speeds ranging between 4 – 6m/s.
Monitored Sea and Land Temperature: Average maximum land surface temperature was 32.0°C in the last week. The Northern plains were the warmest, followed by the Eastern and Southern plains. The sea surface temperature around Sri Lanka ranged between 0.5°C and 1.5°C above average from 01 April to 07th April 2025.
Interpretation
Monitoring
Rainfall: Average Rainfall in the Met Stations for the previous week of (02 Apr – 09 Apr) = 9.6 mm/day. Maximum Daily Rainfall: 79.8 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: Northeasterly winds prevailed over the sea area and around the island last week, with wind speeds ranging between 2–3 m/s.
Temperatures: Cooler temperature anomalies were identified in some parts of the Northern Province, while near-neutral temperature anomalies were identified in other provinces of Sri Lanka from March 30 to April 5.
Prediction
Rainfall: During the next week (April 9–15), “fairly heavy” rainfall (50–100 mm) is predicted for the Western Province, while “moderate” rainfall (25–50 mm) is expected in the Sabaragamuwa, Uva, Central, Eastern, North-Central, Southern, and North-Western Provinces. “Light showers” are expected in the Northern Province.
Temperatures: The temperature will remain above normal in some parts of the Northern and Eastern Provinces from April 10 to April 18, while it will remain normal in other parts of Sri Lanka during this period.
Teleconnections: The MJO will be near neutral, which means it will weaken from April 8 to April 22, resulting in minimal direct influence on rainfall.
Seasonal Precipitation: The precipitation forecast for the April-May-June 2025 season shows more tendency toward normal precipitation across the entire 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 |
