The Meteorology Department today said heavy rains exceeding 100 mm would occur in the Western, North-Western, Sabaragamuwa, and Central Provinces and in the Galle district.
Issuing a weather advisory valid for next 12 hours starting from 8.00 pm today, it said rain fall of over 150 mm could be expected at some places.
There may be temporary localized strong winds during thundershowers, it said.
Meanwhile, one spill gate of Kukule Ganga has been opened since this morning due to the heavy rains experienced in the area, the Disaster Management Centre (DMC) said. (Thilanka Kanakarathna)