Media Center
Climate Bulletin for Sri Lanka (Week of 6 – 13 September 2024)
Highlights
Rainfall Prediction: During 4 Sep – 10 Sep, high likelihood of Light to Moderate rainfall (12.5 – 15 mm/week) is predicted for the North Western province and Light Showers (≤12.5 mm/week) is predicted for the Northern, Eastern, North Central, Southern, Sabaragamuwa, Western, Central, and Uva provinces of SL.
Monitored Rainfall: On average, 4.8 mm/day was received in SL and rainfall was concentrated in the Western plains
(10.8 mm/day) and hills (8.8 mm/day) for last 8 days.On average, 12.2 mm/day was received in the hydro catchments in SL; Kukule Ganga received the highest daily rainfall (70 mm/day) for last 8 days.Highest daily rainfall was in Galle on 30 Aug (56 mm/day).
Monitored and Predicted Wind: From 27 Aug – 4 Sep, winds at 850mb (1.5km) were north west – westerly, reaching up to 15 m/s. From 5 Sep – 11 Sep, winds are predicted to be north west – westerly, reaching up to 15 m/s.
Monitored Sea and Land Temperature: Average land surface temperature was 31.5ºC in the last week with warmer anomalies from seasonal average of 1-3 ºC. Eastern plains was warmest followed by Northern, Southern and Western plains. Sea surface temperature around SL was 0.5°C above average for the Southern side of the country and 1.5°C above average for the other half of the country from 13 – 19 Aug.
Interpretation
Monitoring
Rainfall: During the last two weeks, there has been heavy rainfall over the following area: Vogan Estate (Kalutara) Average Rainfall in the Met stations for the previous week of (29 Aug – 4 Sep) = 4.8 mm/day Maximum Daily Rainfall: 56.0 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: North West – West winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were above normal for some parts of the Southern, Western and Sabaragamuwa province for Sri Lanka driven by the warm SST anomalies.
Prediction
Rainfall:During the next week (4 Sep – 10 Sep ), Light to Moderate rainfall (12.5 – 15 mm) is predicted for the North Western province and Light Showers (12.5 mm) is predicted for the Northern, Eastern, North Central, Southern, Sabaragamuwa, Western, Central, and Uva provinces.
Temperatures: The temperature will remain above normal for the Northern, Eastern, Southern and Uva provinces during 5 – 11 September.
Teleconnections: MJO shall near neutral the rainfall during 3rd September – 7th September and slightly suppress the rainfall during 8th –17th September for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the September-October-November, 2024 season shows a 45% or more tendency toward above normal precipitation for the Eastern 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 |
