The department advises people in the upper part of the country to keep healthy due to the changing weather conditions.
Down in the South, the strong northeast monsoon across the Gulf and the South of Thailand is likely to cause isolated heavy to very heavy rain. The strong wind waves are expected to be 2-3 metres high, so people should be cautious about inshore waves.
All ships should proceed with caution and small ships are advised to stay ashore during the period.
The tropical depression over lower Vietnam has downgraded to active low and is moving west into Cambodia. Thundershowers are likely over the lower Northeast and the Central, the East and the upper South, said the department.