Continuous rains are forecast all over Thailand with isolated heavy rains in some areas.
People in the North, the East and the South have been urged to beware of the severe conditions that may cause flash floods. All ships in the Andaman Sea should proceed with caution and keep away from thundershowers, the department said.
The weather forecast for the next 24 hours is as follows:
Northern region: Mostly cloudy with thundershowers in 60 per cent of the areas and isolated heavy rains; temperature lows of 24-26 degrees and highs of 36-38 degrees Celsius.
Northeastern region: Mostly cloudy with thundershowers in 40 per cent of the areas and isolated heavy rains; temperature lows of 23-25 degrees and highs of 33-36 degrees Celsius.
Central region: Mostly cloudy with thundershowers in 60 per cent of the areas and isolated heavy rains; temperature lows of 23-25 degrees, highs of 35-37 degrees Celsius.
Eastern region: Mostly cloudy with thundershowers in 70 per cent of the areas and isolated heavy rains; temperature lows of 24-27 degrees, highs of 31-35 degrees Celsius; waves 1-2 metres high and two metres during thundershowers.
Southern region (east coast): Mostly cloudy with thundershowers in 60 per cent of the areas and isolated heavy rains; temperature lows of 24-25 degrees, highs of 32-36 degrees Celsius; waves a metre high and two metres during thundershowers.
Southern region (west coast): Mostly cloudy with thundershowers in 70 per cent of the areas and isolated heavy rains; temperature lows of 22-25 degrees, highs of 30-33 degree Celsius; waves 1-2 metres high and two metres during thundershowers.
Bangkok and surrounding areas: Mostly cloudy with thundershowers in 60 per cent of the areas and isolated heavy rains; temperature lows of 24-26 degrees, highs of 32-37 degrees Celsius.