Highlights

Rainfall Prediction: During the following week (5th- 11th October) moderate rainfall is predicted for the Western, Sabaragamuwa, and Central provinces, and less rain is expected for the rest of the country.

Monitored Rainfalls: During the last week, the average daily rainfall in Sri Lanka was 3.5mm, and hydro catchment areas received 22.1 mm on average.

Monitored Wind: From 26th Sep-2nd Oct, up to 15m/s of north-westerly winds were experienced at 850mb level over the island. North-westerly winds are expected next week.

Monitored Sea and Land Temperature: Sea surface temperature around Sri Lanka was above 0.5 °C to the north and west of the country. The land surface temperature remained near normal.

Interpretation

Monitoring

Rainfall: During the last two weeks, there had been heavy rainfall over Kegalle.

Daily Average Rainfall in the Met stations for previous week of (27th Sep – 4th Oct) = 3.5 mm

Rmax: 61.1 mm & Rmin: 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 the southern, Sabaragamuwa and western provinces, driven by the warm SST’s.

Prediction

Rainfall: During the next week (30th September – 4th October) fairly heavy rainfall is predicted for the Sabaragamuwa, Southern and Western provinces, and less rainfall is expected for the rest of the country.

Temperatures: The temperature will remain above normal for the Uva and Eastern provinces from 1st October – 9th October.

Teleconnections: La Niña is favored to continue through Northern Hemisphere winter 2022-23, with a 91% chance in September-November, decreasing to a 54% chance in January-March 2023.
MJO shall be near neutral from 28th September – 12th October for Sri Lanka.

Seasonal Precipitation: The precipitation forecast for the October-November-December 2022 season shows a higher tendency for below-normal precipitation to the southern half of the country.

Terminology for Rainfall Ranges