Highlights

Rainfall Prediction: High likelihood of very heavy rainfall (> 100 mm) is predicted for Eastern province, fairly heavy rainfall (50 – 100 mm) is predicted for Uva, Central provinces and less rainfall (≤ 35 mm) is predicted for the rest during 31 Jan – 6 Feb.

Monitored Rainfall: Rainfall on 28 reached peak (86.5 mm) at Kurundu Oya (CP). During the last week, average daily rainfall was 2.8 mm and hydro catchment was 6.1 mm.

Monitored and Predicted Wind:  Winds at 850mb (1.5 km) were north easterly from 22 – 28 Jan reaching up to 10 m/s. Winds at 850mb (1.5 km) are predicted north easterly from 1 – 7 Feb reaching up to 6 m/s.

Monitored Sea and Land Temperature: Sea surface temperature around Sri Lanka was 0.5 – 1.0ºC above normal. Strong EL Nino and positive indian ocean dipole patterns sustained. Maximum daily temperature was in Ratnapura (35.1ºC), and Ratmalana (34.1ºC).

Climate Bulletin for Sri Lanka (Week of 02 February  – 09 February 2024)

Interpretation

Monitoring

Rainfall: During the last two weeks, there had been fairly heavy rainfall over the following areas:
Kurundu Oya, Poddiwela.
Daily Average Rainfall in the Met stationsfor previous week of (24th January – 31st January) = 2.8 mm
Maximum Daily Rainfall: 41.4 mm & Minimum Daily Rainfall: 0.0 mm.

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

Temperatures: The temperature anomalies were above normal for some parts of the Central, Western, Southern, Northern, Sabaragamuwa, and North Western provinces of the country driven by the warm SST’s.

Prediction

Rainfall: During the next week (31th January – 6th February), heavy rainfall is predicted for the Eastern province, fairly heavy rainfall is predicted for the Uva and Central provinces, and less rainfall is predicted for rest of the country.

Temperatures: The temperature will remain above normal for some parts of the North Western, North Central provinces during 1st- 7th February.

Teleconnections: A positive Dipole Mode has set in across the Indian Ocean since 8th of June. MJO shall moderately suppress the rainfall during 31st January – 4th February, near normal the rainfall during 5th – 9th February, and moderately enhance the rainfall during 10th – 14th February for Sri Lanka.

Seasonal Precipitation: The precipitation forecast for the February-March-April, 2024 season shows near normal precipitation.

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