Media Center
Climate Bulletin for Sri Lanka (Week of 16 – 23 June 2023)
Highlights
Rainfall Prediction: Heavy rainfall is predicted for the Sabaragamuwa, Southern, Western, and Central provinces and fairly heavy rainfall is predicted for the rest of the country during 15 – 21 June.
Monitored Rainfall: During the last week, the average daily rainfall over Sri Lanka was 3.1 mm and hydro catchment areas received 9.9 mm. Highest average rainfall of 8.7 mm/day received in Western
plains.
Monitored and Predicted Wind: From 30 May – 5 June, up to 8 m/s of westerly winds were at 850 mb (1.5 km). During 9 – 15 June, up to 15 m/s of northwesterly winds are expected at 850 mb (1.5 km).
Monitored Sea and Land Temperature: The sea surface temperature around Sri Lanka was 0.5 – 1.5°C above normal. The average maximum land temperature ranged from 32- 33°C and the minimum ranged from 24 – 25°C with a drop in the hills.
Interpretation
Monitoring
Rainfall: During the last two weeks, there had been heavy rainfall over Ratnapura and Avissawella.
Daily Average Rainfall in the Met stations for the previous week of (7th June – 14th June) = 3.1 mm
Maximum Daily Rainfall: 67.1 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: Northwesterly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were above normal for some parts of the Western, Sabaragamuwa, Central, and North Western provinces and near normal for the rest of the country driven by the warm SSTs.
Prediction
Rainfall: During the next week (15th June – 21st June), heavy rainfall (≥ 105 mm) is predicted for the Sabaragamuwa, Southern, Western, and Central provinces, and fairly heavy rainfall (≥ 65 mm) is predicted for the rest of the country.
Temperatures: The temperature will remain above normal for some parts of the Eastern, Northern, Uva, Southern, and North Central provinces from 16th June – 22nd June.
Teleconnections: A large majority of the models indicate El Niño conditions are expected to gradually strengthen into the Northern Hemisphere winter of 2023-24.
MJO shall slightly enhance the rainfall from 15th – 19th June and near neutral from 20th – 29th June for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the July-August-September, 2023 season shows above 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 |
