Highlights

Rainfall Prediction: During 9th- 15th Nov heavy rainfall (≥115mm) is expected for Eastern, North Central, North Western, and Uva provinces.

Monitored Rainfall: During the last week, the average daily rainfall in Sri Lanka was 10.8mm & hydro catchment areas received 11.37 mm on average.

Monitored Wind: From 31st Oct -6th Nov, up to 5m/s of north-westerly and north-easterly winds were experienced at 850 mb level over the island. During 10th-16th Nov, westerly winds are expected to the country.

Monitored Sea and Land Temperature: Sea surface temperature around Sri Lanka was above normal for the whole country in late – October. The land surface temperature remained near normal.

Interpretation

Monitoring

Rainfall: During the last two weeks, there had been heavy rainfall over the following areas: Kegalle, Mullaitivu, Galle, and Rathnapura
Daily Average Rainfall in the Met stations for the previous week of (1st November – 8th November) =16.8 mm
Rainfall max: 116.0 mm & Rainfall min: 0.0 mm.

Wind: North-westerly and North-easterly winds prevailed in the sea area and around the island last week.

Temperatures:  The temperature anomalies were below normal for some parts of the Northern province, and above normal for some parts of the Southern province, driven by the warm SSTs.

Prediction

Rainfall: During the next week (9th – 15th November), above 135 mm rainfall is predicted for the Western, Northern, Southern, and Sabaragamuwa provinces; and heavy (≥ 125 mm) rainfall is expected for the rest of the country.

Temperatures: The temperature will remain below normal for some parts of the Central and Uva provinces from the 10th – 16th November.

Teleconnections: La Niña is favored to continue through during the Northern Hemisphere winter (December-February) 2022-23, with a 54% chance for ENSO-neutral in February-April 2023.
MJO shall near neutral the rainfall during 9th– 23rd November for Sri Lanka.

Seasonal Precipitation: The precipitation forecast for the November-December-January 2023 season shows a higher tendency for above-normal precipitation in the north half of the country.

Terminology for Rainfall Ranges