Media Center
Climate Bulletin for Sri Lanka (Week of 17 May – 24 May 2024)
Highlights
Rainfall Prediction: High likelihood of extreme rainfall (100 – 150 mm) is predicted for the all over the country during 15 – 21 May.
Monitored Rainfall: Only 5/6 of expected rainfall (100mm) was received during 15 April – 14 May. Apart from Western region, a big deficit of rainfall was observed during April.
Monitored and Predicted Wind: Winds at 850mb (1.5 km) were north westerly from 6 – 12 May reaching up to 3 m/s. Winds at 850mb (1.5 km) are predicted north westerly from 16 – 22 May reaching up to 15 m/s.
Monitored Sea and Land Temperature: Average land surface temperature was 33.0°C in the last week with warmer anomalies of +1-3°C. Sea surface
temperature around Sri Lanka was 1.0 – 2.0°C above the seasonal normal. The temperature has dropped slightly.
Interpretation
Monitoring
Rainfall: During the last two weeks, there had been very heavy rainfall over the following area:
Ratmalana.
Daily Average Rainfall in the Met stations for previous week of (8th May – 15th May) = 12.0 mm
Maximum Daily Rainfall: 154.7 mm & Minimum Daily Rainfall: 0.0 mm.
Wind: North westerly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were above normal for the country except some parts of the Northern, Eastern, and Western provinces driven by the warm SST’s.
Prediction
Rainfall: During the next week (15th May – 21st May), heavy rainfall (100 – 150mm) is predicted for the Western, Sabaragamuwa, North Western, Southern, Central, and Uva Provinces and fairly heavy rainfall (50 – 100 mm) is predicted for the rest.
Temperatures: The temperature will remain below normal for some parts of the Central, Western, North Western, Southern, and Uva provinces during 16th – 22nd May.
Teleconnections: MJO shall moderately enhance the rainfall during 16th – 20th May and slightly enhance the rainfall during 21th – 30th May for Sri Lanka.
Seasonal Precipitation: The precipitation forecast for the June-July-August, 2024 season shows a 50% tendency toward above normal precipitation for the country.
Terminology for Rainfall Ranges
| Rainfall | |
| 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 |
