The severe weather warning was triggered by a monsoon trough lying across upper Laos and upper Vietnam and also strengthening of the southwest monsoon over the Andaman Sea, Thailand and the Gulf. The conditions will bring more rain to upper Thailand this week, with isolated heavy rain in the North, Northeast, Bangkok and Central region, the East and the southwest coast.
The department warned vehicles and trains to proceed with caution, while farmers should protect their crops. Ships in the Andaman Sea and the Gulf should also proceed with caution and avoid sailing during thunderstorms.
The weather forecast for June 7-11 is as follows:
North: Rain across 60-70 per cent of region with isolated heavy rain. Temperature lows of 23-27C and highs of 31-37C.
Northeast: Rain in 60-70 per cent of region with isolated heavy rain. Lows of 23-26C and highs of 31-36C.
Central: Rain in 60-70 per cent of region with isolated heavy rain. Lows of 23-28C, highs of 32-37C.
East: Rain in 60-70 per cent of region with isolated heavy rain. Lows of 23-28C, highs of 30-36C; waves 1-2 metres high and over 2 metres during thundershowers.
South (east coast): Rain in 30-40 per cent of area. Lows of 23-28C, highs of 30-36C; waves 1-2 metres and about 2 metres offshore.
South (west coast): Rain in 30-40 per cent of area with isolated heavy rains. Lows of 23-28C, highs of 29-34C; waves 1 metre but rising higher during thundershowers.
Bangkok and vicinity: Rain in 40-60 per cent of area with isolated heavy rains. Lows of 25-28C and highs of 31-36C.