Media Center
Climate Bulletin for Sri Lanka (Week of 19 July – 26 July 2024)
Highlights
Rainfall Prediction: During 24 – 30 July, high likelihood of fairly heavy rainfall (50 – 100 mm) is predicted for the Sabaragamuwa, Western and Southern provinces ; moderate rainfall (25 – 50 mm) is predicted for the Uva, Central and North Western provinces and below 15 mm rainfall is predicted for the rest.
Monitored Rainfall: On average, 1 mm was received in SL and rainfall was concentrated in the Western plains (2.6 mm) and hills (2 mm) for last 8 days. On average, 7.5 mm was received in the hydro catchments in SL; Laxapana (Nuwara Eliya District) received the highest rainfall (43.4 mm) for last 8 days. Highest daily rainfall was in Deraniyagala (Kegalle District) on 23 July (54.5 mm).
Monitored and Predicted Wind: From 17 Jul – 23 Jul, winds at 850mb (1.5km) were westerly and northwesterly, reaching up to 20 m/s. From 26 Jul – 1 Aug, winds are predicted to be north-westerly, reaching up to 10 m/s.
Monitored Sea and Land Temperature: Average land surface temperature was 31ºC in the last week with near neutral anomalies from seasonal average of – 1- +1 ºC. Eastern plains was warmest followed by Southern and Northern plains. Sea surface temperature around Sri Lanka was 0.5 – 1.5ºC above average.
Interpretation
Monitoring
Rainfall: During the last two weeks, there has been fairly heavy rainfall over the following area: Laxapana (Nuwara Eliya District) Daily Average Rainfall in the Met stations for the previous week of (19 July – 24 July) = 1 mm Maximum Daily Rainfall: 21.5 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: Westerly and North Westerly winds prevailed in the sea area and around the island last week
Temperatures: The temperature anomalies were near neutral for Sri Lanka driven by the warm SSTs.
Prediction
Rainfall: : During the next week (24 July – 30 July), fairly heavy rainfall (50 – 100 mm) is predicted for the Sabaragamuwa, Western and Southern provinces and moderate rainfall (25 – 50 mm) is predicted for the Uva, Central and North Western provinces and light showers are predicted for the rest.
Temperatures: The temperature will remain above normal for the Northern, Eastern, North Central, and Uva provinces during 26 July – 2 August.
Teleconnections: MJO shall be near neutral for the rainfall during 24 July-7 August for Sri Lanka
Seasonal Precipitation: The precipitation forecast for the July-August-September, 2024 season shows a 40% or more tendency toward normal precipitation for 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 |
