Highlights

Rainfall Prediction: Up to 75 mm of fairly heavy rainfall is expected to receive for the Central province from 18th -23rd March while other provinces are expected to receive less.

Monitored Rainfalls: Heavy rainfall was experienced in the Western & Southern provinces, with a maximum of 126.5 mm in the Gampaha district on 12th March.

Monitored  Wind: From 8th- 14th March, up to 6m/s North-easterlies were experienced over the island.

Monitored  Temperature: Sea surface temperatures were neutral around the entire island.

Climate Bulletin for Sri Lanka (Week of 18 Mar – 25 Mar 2022)
Climate Bulletin for Sri Lanka (Week of 18 Mar – 25 Mar 2022)

Interpretation

Monitoring

Rainfall: During the last two weeks, there had been heavy rainfall over the following provinces:
Western and Southern.

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

Temperatures: The temperature anomalies were below normal for the Norther province and near-neutral for the rest of the country, driven by the warm SST’s.

Prediction

Rainfall: During the next week (17th – 23rd March) fairly heavy rainfall is predicted for Central province.

Temperature : The temperature remains slightly above normal in the Northern and Eastern provinces during 19th – 27th March.

Teleconnections:

La Nina – The SST forecast indicates that La Niña isfavored to continue into the Northern Hemisphere summer (June-August 2022).

MJO shall significantly enhance the rainfall from 17th – 21st March; and slightly enhance during 22nd– 31st March.

Seasonal Precipitation:

The precipitation forecast for the April-May-June season shows above-normal precipitation for the island, while some parts of the southern province remain neutral.

Cyclone Alert

The low pressure zone over Southeast Bay of Bengal moved east-northeastwards and was centered over the Southeast Bay of Bengal and adjoining south Andaman Sea around 08.30 a.m. on March 18th. By the 20th of March, it is expected to continue moving east-northeastwards and deepen into a depression. Over the aforementioned sea areas, there may be extremely heavy rains or thundershowers, strong winds (40-50) kmph gusting up to 60 kmph, and very choppy seas.

Terminology for Rainfall Ranges

Rainfall (During 24 hours of 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