Sri Lanka Weather Forecast: Southwest Monsoon Strengthens Bringing Heavy Rain and Rough Seas on 25 May 2026
The Southwest Monsoon is gradually establishing across Sri Lanka, with an increase in rainfall expected over the southwestern parts of the island during the next few days, according to the latest weather forecast issued at 5.30 a.m. on 25 May 2026 by the Department of Meteorology.
Showers or thundershowers are expected at times in the Western, Sabaragamuwa and North-western provinces as well as in Galle, Matara, Kandy and Nuwara-Eliya districts. Fairly heavy rainfall exceeding 75 mm is likely at some locations in these areas, raising concerns over localized flooding and water accumulation in low-lying regions.
Meanwhile, a few showers or thundershowers may develop after 1.00 p.m. in the Uva and Eastern provinces. Residents in affected areas are advised to remain vigilant, especially during periods of intense rainfall and lightning activity.
In addition to the rainy conditions, fairly strong winds of around 30-40 kmph are expected at times over the western slopes of the central hills and in the Northern, North-central, North-western and Southern provinces, including the Trincomalee district. The public has been requested to take adequate precautions to minimize possible damage caused by temporary strong winds and lightning during thundershowers.
Sea conditions around the island are also expected to remain unsettled over the next 24 hours. Showers or thundershowers are forecast in sea areas extending from Puttalam to Hambantota via Colombo and Galle, while isolated showers may occur in other surrounding sea regions during the evening or night.
Southwesterly winds over the sea will range between 30-40 kmph and may strengthen up to 50-60 kmph at times in the sea areas from Kankasanthurai to Chilaw via Mannar and from Galle to Pottuvil via Hambantota. Other sea areas around the island may also experience winds up to 50 kmph.
As a result, the sea areas off the coasts from Kankasanthurai to Chilaw via Mannar and from Galle to Pottuvil via Hambantota will be rough at times, while other sea areas will remain fairly rough. Wave heights may increase between 2.0 and 2.5 meters in coastal waters from Puttalam to Pottuvil via Colombo, Galle and Hambantota.
Naval and fishing communities are strongly advised to exercise caution due to temporarily strong gusty winds and very rough seas during thundershowers.