Showers or thundershowers will occur at several places in most parts of the island after 1 p.m., the Department of Meteorology said.
Fairly heavy rainfall of over 75 mm is likely at some locations in the Central, Sabaragamuwa, Uva, North Central and Eastern provinces.
The public has been requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
Showers or thundershowers may occur at a few places in sea areas off the coast extending from Hambantota to Trincomalee via Pottuvil and Batticaloa during the evening or night.
Winds will be southwesterly or variable at 20-30 kmph, while the sea will be slight to moderate.