Media Center
Climate Bulletin for Sri Lanka (Week of 23 – 30 June 2023)
Highlights
Rainfall Prediction: Fairly heavy rainfall is predicted for the Sabaragamuwa, Southern, Western, Central, and Uva provinces and less rainfall is predicted for the rest of the country during 22 – 28 June.
Monitored Rainfall: During the last week, the average daily rainfall over Sri Lanka was 1.7 mm, and hydro catchment areas received 3.4 mm. The highest average rainfall of 2.5 mm/day was received in the Western region.
Monitored and Predicted Wind: From 13 – 19 June, up to 15 m/s of northwest-westerly winds were at 850mb (1.5 km). During 23 – 29 June, up to 15 m/s of northwesterly winds are expected at 850 mb (1.5km).
Monitored Sea and Land Temperature: The sea surface temperature around Sri Lanka was 0.5 – 1.5°C above normal. •Average maximum land temperature ranged from 29- 33°C and minimum ranged from 24 – 25°C with a drop in the hills.
Interpretation
Monitoring
Rainfall: Rainfall: During the last two weeks, there had been fairly heavy rainfall over Kegalle, Ampara
Daily Average Rainfall in the Met stations for the previous week of (14th June – 21st June) = 1.7 mm
Maximum Daily Rainfall: 30.5 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 Uva, Sabaragamuwa, and Central provinces and some parts of the Northern, Southern, Eastern, and North Western provinces driven by the warm SSTs.
Prediction
Rainfall: During the next week (22nd June – 28th June), fairly heavy rainfall (≥ 55 mm) is predicted for the Sabaragamuwa, Southern, Western, Central, and Uva provinces and less rainfall is predicted for the rest of the country.
Temperatures: The temperature will remain above normal for some parts of the Uva, Eastern, Northern, Southern, and North Central provinces from 23rd June – 29th June.
Teleconnections: El Niño conditions are expected to gradually strengthen into the Northern Hemisphere winter of 2023-24.
MJO shall slightly suppress the rainfall from 22nd – 26th June, near neutral from 27th June – 1st of July, and slightly enhance the rainfall from 2nd – 6th of July 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 |
