The South-West monsoon is gradually establishing over Sri Lanka, the Department of Meteorology said on Tuesday, with showers and thundershowers expected across several provinces and seas turning rough off long stretches of the coast.
Showers or thundershowers will occur at times in the Western, Sabaragamuwa, Central and North-western provinces and in the Galle and Matara districts on May 19, the department said. Several spells of showers are forecast for the Northern province and the Anuradhapura and Hambantota districts. Uva and Eastern provinces and the Polonnaruwa district may see showers after 2pm.
Fairly strong winds of 30 to 40 kmph are likely over the western slopes of the central hills, the Northern, North-central and North-western provinces and the Hambantota district. The public has been asked to take precautions against temporary localised strong winds and lightning during thunderstorms.
The sea will be rough at times off coasts extending from Trincomalee to Pottuvil via Kankasanthurai, Puttalam, Colombo, Galle and Hambantota. Winds will be south-westerly at 30 to 40 kmph, potentially strengthening to 50 to 60 kmph off the stretch from Kankasanthurai to Puttalam via Mannar and Trincomalee.
A separate marine warning issued by the department in the evening flagged rough seas and strong winds over the Bay of Bengal and Arabian Sea regions for the next three days, with wind speeds expected to reach 40 to 50 km/h and gust temporarily to 60 km/h. Heavy rainfall above 50 mm is possible in some inland areas, the department added, with showers or thundershowers extending into the evening or night in much of the island.
The onset confirms forecasts of a near-normal monsoon for June to September issued earlier this month, and follows several days of pre-monsoonal weather that left 204 houses damaged across 13 districts. Hydropower reservoirs and Yala season planting both depend on a strong South-West monsoon.
