The Meteorological Department has issued a first category warning on strong winds and rough seas occuring in the waters off Phuket, Reef North, Reef South, Layang-Layang, Palawan, Labuan and Sulu.

According to the department's statement, the strong west-southwesterly winds of 40-50 kmph with waves up to 3.5 metres were expected to occur until Sunday.

This condition of strong winds and rough seas is dangerous to small crafts, recreational sea activities and sea sports, the statement said.

The department also said that thunderstorms occurring over the west coast of Sabah, Pendalaman and Labuan were expected to persist until tomorrow.