Media Center
Climate Bulletin for Sri Lanka (Week of 02 Sep – 09 Sep 2022)
Highlights
Rainfall Prediction: Up to 80 mm of rainfall is predicted for Central and Sabaragamuwa provinces, below 75mm of rainfall is expected for the rest of the country during 2nd -7th September.
Monitored Rainfalls: During the last week,the average daily rainfall over Sri Lanka was 5.6 mm and hydro catchment areas have received 10.13 mm on average.
Monitored and Predicted Wind: From 22nd – 28th August, southwesterly of 10m/s winds were experienced at 850mb level over the island. Upto 10m/s of westerlies to south-westerly winds expected for the next week.
Monitored Sea and Land Temperature: Sea surface temperature around Sri Lanka was above 0.5℃ to the north of Sri Lanka. Land surface temperature remained near normal
Interpretation
Monitoring
Rainfall:
During the last two weeks, there had been fairly heavy rainfall over the following area: Polonnaruwa
Daily Average Rainfall in the Met stations for previous week of (22nd Aug – 29th Aug) = 5.6 mm
Rainfall maximum: 102.5 mm & Rainfall minimum: 0.0 mm.
Wind: South-westerly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were below normal for the northern half of the island, driven by the warm SST’s
Prediction
Rainfall:During the next week (2nd – 6th September) up to 80 mm of rainfall is predicted for Central and Sabaragamuwa provinces, and < 75mm rainfall is expected for the rest of the country.
Temperatures: The temperature will remain slightly above normal for the Uva province during 2nd September – 7st September
Teleconnections: La Niña – La Niña is expected to continue, with chances for La Niña gradually decreasing from 86% in the coming season to 60% during December-February 2022-23.
MJO shallslightly enhance the rainfall during 31st August – 4th September and shall near neutral during 5th September – 14th September
Seasonal Precipitation: The precipitation forecast for the September-October-November season shows a higher tendency for below-normal precipitation for the country.
Terminology for Rainfall Ranges
| Rainfall (During 24 hours of 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 |
