More rain, with isolated heavy to very heavy falls, is forecast for the North, Central, East and South regions on Monday and Tuesday, brought by a tropical depression over the centre of the Bay of Bengal.
The Meteorological Department said on Monday morning that as of 4am the storm was moving in a north-northwesterly direction at 12 kilometres per hour with maximum sustained winds about 55kph.
It was expected to make a landfall over Myanmar on Tuesday.
This, in conjunction with the strong southerly and southeasterly winds prevailing across the North, Central, East and South regions of Thailand, meant more rain, with isolated heavy to very heavy falls, was expected in most areas on March 21-22.
Strong winds and waves 2-3 metres high were likely in the upper Andaman Sea, about 3m high during thundershowers and 1-2m high in the lower Andaman Sea and the Gulf of Thailand, about 2m high in thundershowers. All vessels were advised to proceed with caution and keep away fom thundershowers.
Small boats in the upper Andaman Sea should keep ashore until March 22.