Highlights

Rainfall Prediction: During 2 – 8 Oct, high likelihood of Fairly Heavy rainfall (50-100 mm) is predicted for the North Central, Eastern, Western and Northern provinces and Moderate rainfall (25-  50 mm) is predicted for the Central, Southern, North Western, Sabaragamuwa and Uva provinces.

Monitored Rainfall: On average, 4.5 mm/day was received in SL and rainfall was concentrated in the Western plains (6.0 mm/day) and hills (8.6 mm/day) for last 8 days. On average, 7.2 mm/day was received in the hydro catchments in SL; Kukule Ganga received the highest daily rainfall (107mm/day) for last 8 days. Highest daily rainfall was in Ratnapura on 24 Sep (73.8 mm/day).

Monitored and Predicted Wind: From 17 Sep – 23 Sep, From 24 Sep – 30 Sep, winds at 850mb (1.5km) were north westerly, reaching up to 5 m/s. From 4 – 10 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. Northern plains was warmest followed by Eastern, Southern and Western plains. Sea surface temperature around Sri Lanka was 1.0℃ above average from 3 – 9 Sep 2024.

 

Climate Bulletin for Sri Lanka (Week of  4 –  11 October  2024)

 

Interpretation

Monitoring

Rainfall: During the last two weeks, there has been Very Heavy rainfall over the following area: Dellawa (Matara District). Average Rainfall in the Met stations for the previous week of (26 Sep- 2 Oct) = 4.5 mm/day Maximum Daily Rainfall: 73.8 mm & Minimum Daily Rainfall: 0.0 mm.

Wind: North 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 Northern, North Central, Eastern and North Western provinces driven by the warm SSTs anomalies.

Prediction

Rainfall: During the next week (2 – 8 October), Fairly Heavy rainfall (50-100 mm) is predicted for the North Central, Eastern, Western and Northern provinces and Moderate rainfall (25-50 mm) is predicted for the Central, Southern, North Western, Sabaragamuwa and Uva provinces.

Temperatures: The temperature will remain above normal for the Northern, Eastern, North Central and Uva provinces during 4 Oct – 10 Oct

Teleconnections: MJO shall be slightly enhance for the rainfall during 3-7 October and near neutral the rainfall during 8-17 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 ShowersLess than 12.5 mm
Light to ModerateBetween 12.5 mm and 25 mm
ModerateBetween 25 mm and 50 mm
Fairly HeavyBetween 50 mm and 100 mm
HeavyBetween 100 mm and 150 mm
Very HeavyMore than 150 mm