Highlights

Rainfall Prediction: Heavy rainfall is predicted for Jaffna districts; fairly heavy rainfall (50–100 mm)is expected for Sabaragamuwa, Central, and Uva provinces and Galle and Matara districts during 29 Jul – 2 Aug.

Monitored Rainfalls: During the last week, the average daily rainfall over Sri Lanka was 6.7 mm and hydro catchment areas have received 11.6 mm on average.

Monitored  Wind: From 18th- 24th July, up to 10 m/s of south-westerly and north-westerly winds were experienced over the island.

Monitored  Temperature: Sea surface temperature was above 0.5°C to the North and East of Sri Lanka. Land surface temperature remained near normal.

Interpretation

Monitoring

Rainfall: During the last two weeks, there had been heavy rainfall over the following area: Galle
Daily Average Rainfall in the Met stations for previous week of (19th July – 26th July) = 6.7 mm

Rainfall maximum: 105.3 mm & Rainfall minimum: 0.0 mm.

Wind: South-westerly and North-westerly prevailed in the sea area and around the island last week.

Temperatures: The temperature anomalies were above normal for Sabaragamuwa province and below normal for the north-central and eastern provinces, driven by the warm SST’s.

Prediction

Rainfall: During the next week (29th July – 2nd August) heavy rainfall is predicted for Jaffna districts and fairly heavy rainfall (50 – 100 mm) is expected for Central, Sabaragamuwa and Uva provinces and Galle and Matara districts.

Temperatures: The temperature remains above normal in the Northern province during 28th July –3rd August.

Teleconnections: La Niña – La Niña is favored to continue through 2022 with the odds for La Niña decreasing into the Northern Hemisphere late summer (July-September 2022) before increasing through the Northern Hemisphere fall and early winter 2022.

MJO shall slightly enhance the rainfall during 27th July – 5th August; and near-neutral during 6th August– 10th August.

Seasonal Precipitation:

The precipitation forecast for the August-September-October season shows a higher tendency for below-normal precipitation for the southern half of the country, while the remaining areas are more likely to experience near-normal precipitation.

Terminology for Rainfall Ranges