Highlights

• Rainfall Prediction : Fairly heavy rainfall is predicted for Central, Eastern, Western, Southern and Sabaragamuwa provinces during 8th – 12th Oct. Greater likelihood of dry tendency is predicted for southern Sri Lanka from Oct to Dec.
• Monitored Rainfalls : Heavy rainfall was experienced in Central, North- Central, Uva and Western provinces with max of 142.0 mm in Polonnaruwa district on 2nd Oct according to ground observations.
• Monitored Wind : From 28th Sept – 4 th Oct, up to 35 km/h Westerlies and Southwesterlies were experienced across the island.
• Monitored Sea Surface : Sea surface temperature was observed above 0.5℃ all around Sri Lanka.

Interpretation

Monitoring

Rainfall  : During the last two weeks, there had been heavy rainfall over the following Provinces: Central, North-Central, Uva and Western.uring the next week (8th – 12th October) fairly heavy rainfall is predicted for Central, Eastern, Sabaragamuwa, Southern, and Western provinces.

Wind : Westerly to South westerly winds prevailed in the sea area and around the island during last week.

Temperatures:  The temperature anomalies were below normal by 10C – 30C in Eastern and North Central provinces while near-neutral for the rest of the country last week, driven by the warm SST’s.

Prediction

Rainfall : During the next week (8th- 12thOctober) fairly heavy rainfall is predicted for Central, Eastern, Sabaragamuwa, Southern, and Western provinces.

Temperatures : The temperature remains slightly normal for September. During 8th – 16th October, the temperature remains high especially in the Eastern and Uva provinces.

Teleconnections:
La Nina -The SST forecast indicates that ENSO-neutral are present and a transition from ENSO-neutral to La Niña is favored in the next couple of months. MJO shall be active, thus giving slightly suppressed rainfall during 6th – 20th October.

Seasonal Precipitation :  October to December is the main rainfall season in Sri Lanka. The consensus predictions has switched from neutral to favoring a dry tendency. A dry tendency can hurt agricultural production and it adds to farmer difficulties due to the fertilizer bans. However, since this is the wet season the impact will not be as severe.
However, the bigger impact shall be that it shall reduce the generated hydropower in the coming
months. This can hurt the economy due to the scarcity in Foreign Exchange within the country due to the Central Bank regulations.

Understanding the Forecast :