People in these areas should beware of heavy rain, it warned.
Here’s the weather forecast for the next 24 hours:
Northern region: Partly cloudy with thundershowers in 20 per cent of the area; temperature lows of 24-27 degrees and highs of 34-38 degrees Celsius.
Northeastern region: Partly cloudy with thundershowers in 30 per cent of the area; temperature lows of 24-27 degrees and highs of 36-37 degrees Celsius.
Central region: Partly cloudy with thundershowers in 30 per cent of the area; temperature lows of 25-27 degrees, highs of 36-38 degrees Celsius.
Eastern region: Mostly cloudy with thundershowers in 60 per cent of the area and isolated heavy rains; temperature lows of 25-27 degrees, highs of 31-36 degrees Celsius; waves a metre high and 2 metres during thundershowers.
Southern region (east coast): Mostly cloudy with thundershowers in 60 per cent of the area and isolated heavy rains; temperature lows of 24-26 degrees, highs of 32-36 degrees Celsius; waves a metre high and 1-2 metres during thundershowers.
Southern region (west coast): Mostly cloudy with thundershowers in 60 per cent of the area and isolated heavy rains; temperature lows of 24-25 degrees, highs of 31-33 degrees Celsius; waves a metre high and 2 metres during thundershowers.
Bangkok and surrounding areas: Mostly cloudy with thundershowers in 40 per cent of the area; temperature lows of 25-27 degrees, highs of 34-37 degrees Celsius.