Mountaintops are cold to very cold with frost in some areas. People should watch their health due to the variable weather, the department said.
Meanwhile, the moderate northeast monsoon prevails across the Gulf of Thailand and the South with isolated thundershowers. The moderate winds in the Gulf force waves up 1-2 metres high. All ships should proceed with caution, the department said.
Forecast for 24 hours:
Bangkok and surrounding areas: Cool morning; minimum temperature 21-23 degrees Celsius, maximum 31-34°C; northeasterly winds 10-25kph.
North: Cool to cold and 1-2°C drop in temperature; minimum temperature 12-17°C, maximum 29-33°C; cold to very cold on mountaintops with frost in some places; minimum temperature 3-13°C; northeasterly winds 10-25kph.
Northeast: Cool to cold with strong winds and 1-2°C drop in temperature; minimum temperature 12-17°, maximum 29-32 °C; Cold on the mountaintop: minimum temperature 7-13°C; northeasterly winds 15-30kph.
Central: Cool morning with slight drop in temperature; minimum temperature 17-20°C, maximum 31-33°C; northeasterly winds 15-25kph.
East: Cool morning with strong winds; minimum temperature 18-23°C, maximum 31-33°C; northeasterly winds 15-30kph; waves about a metre high and 1-2 metres offshore.
South (east coast): Partly cloudy with isolated thundershowers; minimum temperature 21-24°C, maximum 31-32°C; northeasterly winds 15-35kph; waves 1-2 metres high.
South (west coast): Partly cloudy with isolated thundershowers; minimum temperature 22-24°C, maximum 32-33°C; northeasterly winds 15-35kph; waves about a metre high and 1-2 metres high offshore.