The Department of Meteorology says that thundershowers accompanied by severe lightning are likely to occur in Eastern and North-Central provinces.
Issuing an advisory on lightning and heavy rain, it said that temporarily strong gusty winds up to 70-80kmph are also possible during thundershowers while fairly heavy rainfall above 75 mm is likely at some places.
The department also issued an advisory for heavy rain and strong winds in the sea areas off the coast extending from Mullaitivu to Pottuvil via Trincomalee.
Due to the active cloudiness in the Eastern sea areas, the possibility for heavy showers/thundershowers and sudden roughness, associated with sudden increase of wind speed (up to 70-80 kmph) in the above given sea areas is high, it said.
Naval and fishing communities are also requested to be vigilant in this regards.
The department said that the active cloud formed in the Eastern sea areas to the island is likely to persist further.