Media Center
Climate Bulletin for Sri Lanka (Week of 28 Apr – 05 May 2023)
Highlights
Rainfall Prediction: Heavy rainfall is predicted for the Sabaragamuwa, Western, Southern, Central, Uva, North Western, North Central, and Eastern provinces during 27 th Apr – 3rd May.
Monitored Rainfall: During the last week, the average daily rainfall over Sri Lanka was 6.5mm and hydro catchment areas received 7.6 mm.
Monitored Wind: From 18th – 24th Apr, up to 2 m/s of Southerly winds were experienced at 850mb level over the island.
Monitored Sea and Land Temperature: The sea surface temperature around Sri Lanka was about one degree above the seasonal norm. The maximum land surface across Sri Lanka ranged from 30 – 35°C with a drop in the hills.
Interpretation
Monitoring
Rainfall: During the last two weeks, there had been heavy rainfall over Moneragala.
Daily Average Rainfall in the Met stations for the previous week of (18th April – 25th April) = 6.5 mm
Maximum Daily Rainfall: 142.0 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: Southerly 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, Southern, Western, and Central provinces and near normal for rest of the country driven by the warm SSTs.
Prediction
Rainfall: During the next week (27th April – 3rd May), heavy rainfall (≥ 125 mm) is predicted for the Sabaragamuwa, Western, Southern, and Central provinces and ≥ 105 mm rainfall is predicted for the Uva, North Western, North Central, and Eastern provinces of the country.
Temperatures: The temperature will remain above normal for some parts of the Northern, North Western, North Central, Uva, Eastern, and Southern provinces during 2th April – 4th May.
Teleconnections: ENSO-neutral conditions are expected to continue through the Northern Hemisphere spring, followed by a 62% chance of El Nino developing during May and July 2023.
MJO shall moderately enhance the rainfall from 27th April – 11th 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 |
