Highlights

Rainfall Prediction: Moderately heavy rainfall is predicted for the Eastern province and less rainfall is predicted for the rest of the country from 29th December- 4th of January.
The seasonal forecast shows a higher tendency for above-normal precipitation in the country for January – March 2023.

Monitored Rainfall: During the last week, hydro catchment areas received 77.5mm of maximum rainfall. Due to depression over the island, floods and landslides were experienced in the Kandy district.

Monitored Wind: During the last week, strong winds and rough seas were experienced due to a depression over the southwest Bay of Bengal.

Monitored Sea and Land Temperature: Sea surface temperature around Sri Lanka was near neutral to the whole country. The land surface temperature remained near normal.

Climate Bulletin for Sri Lanka (Week of 30 Dec 2022 – 06 Jan 2023)

Interpretation

Monitoring

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

Daily Average Rainfall in the Met stations for the previous week of (21st December – 28th December) =10.1 mm

Rainfall max: 106.5 mm & Rainfall min: 0.0 mm.

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

Wind: Northeasterly winds prevailed in the sea area and around the island last week.

Prediction

Rainfall: During the next week (29th Dec – 4th Jan), moderately heavy rainfall is predicted for the Eastern province; and less 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 30th December – 5th January.

Teleconnections: La Niña is favored to continue into the winter, with equal chances of La Niña and ENSO-neutral during January-March 2023.

MJO shall moderately suppress the rainfall from 29th December – 2nd January, slightly suppress the rainfall from 3rd – 7th January, and near neutral the rainfall from 8th– 12th January for Sri Lanka.

Seasonal Precipitation: The precipitation forecast for the January-February-March 2023 season shows a higher tendency for above-normal precipitation to the country.

Terminology for Rainfall Ranges

Rainfall (During 24 hours of the period)
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