Media Center
Climate Bulletin for Sri Lanka (Week of 20 – 27 December 2024)
Highlights
Rainfall Prediction: During the next week (18–24 Dec), Fairly Heavy rainfall is predicted for the Northern province, Moderate rainfall is predicted for the North Central and Eastern provinces, Light to Moderate rainfall is predicted for the Western, North Western, Sabaragamuwa, Uva, and Central provinces, and Light Showers are predicted for the Southern province.
Monitored Rainfall: During the last 8 days, Sri Lanka received an average of 11.5 mm/day of rainfall, while in the hydro catchments, the average rainfall was 11 mm/day. The highest daily rainfall was recorded in Anuradhapura on 12 Dec (113 mm/day).
Monitored Sea and Land Temperature: Average land surface temperature was 31.0ºC in the last week, with warmer anomalies from the seasonal average of 1-3 ºC. The Southern plains were the warmest, followed by the Western and Eastern plains. Sea surface temperature around Sri Lanka was 1℃ above average from 4 Dec – 11 Dec 2024.
Interpretation
Monitoring
Rainfall:During the last two weeks, there has been Very Heavy rainfall over the following area: 182.5 mm/day (Rambaawa-Anuradhapura) Average Rainfall in the Met stations for the previous week of (12 – 18 Dec) = 11.6 mm/day Maximum Daily Rainfall: 113.3 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 warmer for Sri Lanka except for Northern province and some parts of Western, North Central, North Western, Southern and Eastern provinces driven by the warm SSTs anomalies.
Prediction
Rainfall: During the next week (18 – 24 Dec), Fairly Heavy rainfall (50-100 mm) is predicted for the Northern province, and Moderate rainfall (25-50 mm) is predicted for the North Central and Eastern provinces, and Light to Moderate rainfall (12.5mm-25mm) is predicted for the Western, North Western, Sabaragamuwa, Uva and Central provinces, and Light Showers (<12.5mm) are predicted for the Southern province.
Temperatures: The temperature will remain normal for the SL during 21 – 27 Dec.
Teleconnections: MJO shall be moderately enhance for the rainfall during 18 Dec-1 Jan for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the January-February-March, 2025 season shows a 50% or more tendency toward above-normal precipitation for the Northern half of the country, while it shows a 60% or more tendency toward above-normal precipitation for the Southern half of the country.
Terminology for Rainfall Ranges
| Rainfall | |
| 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 |
