Media Center
Climate Bulletin for Sri Lanka (Week of 11 – 18 October 2024)
Highlights
Rainfall Prediction: During 9 – 15 Oct, high likelihood of Extremely heavy rainfall is predicted for the SL. The districts of Galle, Matara, Kegalle, Ratnapura, Kalutara, Gampaha, and Colombo are forecast to experience very high and unusual rainfall on 12, 13 and 14 October 2024.
Monitored Rainfall: On average, 10.2 mm/day was received in SL and rainfall was concentrated in the Western plains (21.6 mm/day)) for last 8 days. On average, 4.8 mm/day was received in the hydro catchments in SL; Randenigala received the highest daily rainfall (84 mm/day) for last 8 days. Highest daily rainfall was in Colombo on 6 Oct (168 mm/day).
Monitored and Predicted Wind: From 30 Sep – 6 Oct, winds at 850mb (1.5km) were south westerly, reaching up to 10 m/s. From 10 – 16 Oct, winds are predicted to be westerly, reaching up to 15 m/s
Monitored Sea and Land Temperature: Average land surface temperature was 31.0ºC in the last week with warmer anomalies from seasonal average of 1-3 ºC. Eastern plains was warmest followed by Southern and Northern plains. Sea surface temperature around Sri Lanka was 1.0℃ above average from 12 – 18 Sep 2024.
Interpretation
Monitoring
Rainfall: During the last two weeks, there has been Very Heavy rainfall over the following area: Dummalasooriya (Kurunegala). Average Rainfall in the Met stations for the previous week of (3 Oct- 8 Oct) = 10.2 mm/day Maximum Daily Rainfall: 168 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: South Westerly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were above normal for Sri lanka except some parts of North Central, Southern, Sabaragamuwa, Uva and Eastern provinces driven by the warm SSTs anomalies.
Prediction
Rainfall: During the next week (9 – 15 October), Heavy rainfall (≥135 mm) is predicted for the North Central, Eastern, Western, Central, Southern, North Western, Sabaragamuwa, Northern and Uva provinces.
Temperatures: The temperature will remain normal for the SL during 10 Oct – 16 Oct.
Teleconnections: MJO shall be slightly enhance for the rainfall during 9-13 October and near neutral the rainfall during 14-23 October for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the October-November-December, 2024 season shows a 40% or more tendency toward above-normal precipitation for the Northern part 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 |
