Cold air carried by a strong high-pressure system from China will blanket Thailand and the South China Sea, also bringing strong winds to the whole region, the TMD said on Wednesday.
Temperatures are set to fall by 5-7C in the North and Northeast and by 2-5C in Bangkok and the Central, East and upper South regions.
“The public should guard their health and beware of fire due to strong winds and dry air,” the department cautioned.
The TMD also forecast rain for the South and isolated heavy rain for the lower South, as the monsoon strengthens.
Waves in the Gulf are forecast to rise above four metres in thundershowers, while the Andaman Sea will see waves exceed 2 metres in thundershowers and offshore.
People on the east of the peninsula were advised to beware of inshore surges from the Gulf of Thailand.
“All ships should proceed with caution and keep off thundershowers,” the department said, adding that small boats in the Gulf should keep ashore from January 10-13.
Today’s weather forecast
North: Cool to cold with morning fog and 1-2C increase in temperature: minimum 12-19C, maximum 27-32C. Mountaintops to see very cold weather and isolated frost, with temperatures falling to 3-9C.
Northeast: Cool to cold with light morning fog and 1-2C increase in temperature. Minimum 12-17C, maximum 29-32C. Mountaintops cold to very cold (6-10C).
Central: Cool with light morning fog and 1-2C increase in temperature. Minimum 18-20C maximum 32-34C.
East: Cool with light morning fog and 1-2C increase in temperature. Minimum 18-23C, maximum 32-34C.
South (east coast): Morning cool in the upper part and 1-2C increase in temperature. Isolated thundershowers in Pattani, Yala and Narathiwat. Minimum 20-24C, maximum 31-33C.
South (west coast): Isolated thundershowers in Trang and Satun. Minimum 23-26C, maximum 33-34C.
Bangkok and environs: Morning cool with light fog and 1-2C increase in temperature. Minimum 20-23C, maximum 32-34C.