Farmers in upper Thailand should take measures to prevent damage to crop due to the weather conditions, the Thailand Meteorological Department warned.
Meanwhile, the moderate northeast monsoon prevailing over the Gulf and the South will bring isolated heavy rains to the South, the department said.
Waves in the Gulf of Thailand could rise 2 metres high and over 2 metres during thundershowers, while those in the Andaman Sea would be 1-2 metres high and over 2 metres in thundershowers, the department said.
People in the lower South should beware of heavy to very heavy rains that may cause flash floods and overflows, especially along foothills near waterways and lowlands. All ships should proceed with caution and keep off thundershowers, the department said.