Media Center
Climate Bulletin for Sri Lanka (Week of 21 Apr – 28 Apr 2023)
Highlights
Rainfall Prediction: Fairly heavy rainfall is predicted for the Sabaragamuwa, Southern, Western, Central and North Western provinces and less rainfall is expected for rest of the country during 20th Apr – 26th Apr.
Monitored Rainfall: During the last week, average daily rainfall over Sri Lanka was 2.0 mm and hydro catchment areas received 4.3 mm.
Monitored Wind: From 11th – 17th Apr, up to 5 m/s of Easterly winds were experienced at 850 mb level over the island.
Monitored Sea and Land Temperature: Sea surface temperature was about one degree above the seasonal norm. The maximum land surface across Sri Lanka ranged from 30 – 35ºC with a drop in the hills.
Interpretation
Monitoring
Rainfall: During the last two weeks, there had been heavy rainfall over Bandarawela.
Daily Average Rainfall in the Met stations for previous week of (12th April – 19th April) = 2.0 mm
Maximum Daily Rainfall: 64.0 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: 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 Sabaragamuwa
province and near normal for rest of the country driven by the warm SST’s
Prediction
Rainfall: During the next week (20th April – 26th April), fairly heavy rainfall (≥ 55 mm) is predicted for the Southern, Sabaragamuwa, Western, Central, and North Western provinces, and less rainfall is expected for rest of the country.
Temperatures: The temperature will remain above normal for some parts of the Northern, Northwestern, North Central, Uva, Eastern, and Southern provinces during 21st April – 27th April.
Teleconnections: ENSO-neutral conditions are expected to continue through the Northern Hemisphere spring, followed by a 62% chance of El Nino developing during May-July 2023.
MJO shall slightly suppress the rainfall during 20th – 24th April, and slightly enhance the rainfall during 25th April – 4th May for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the May-June-July, 2023 season shows near normal precipitation for the country.
Terminology for Rainfall Ranges
| Rainfall (During 24 hours of the period) | |
| Light Showers | Less than 12.5 mm |
| Light to Moderate | Between 12.5 mm and 25 mm |
| Moderate | Between 25 mm and 50 mm |
| Fairly Heavy | Between 50 mm and 100 mm |
| Heavy | Between 100 mm and 150 mm |
| Very Heavy | More than 150 mm |
