The first breath of winter is being felt in many provinces, with temperatures dropping and cool, breezy days in the northern half of the country, including Bangkok, and the weatherman forecasting a further fall of 1-3°C.
In the Northeast, the mercury fell to 19°C in Nakhon Phanom on Wednesday morning.
In the North, Doi Ang Khang, in the mountainous district of Fang in Chiang Mai, recorded 15°C.
The Meteorological Department said the capital will experience "windy" weather with a continual drop in temperatures of up to 2°C, and a further one-notch down in the North and Northeast.
"People should take care of their health due to the weather change," the statement said.
But the colder weather also means a happy time for traveling.
Nakhon Phanom governor Siam Sirimongkhon invited tourists to visit to his province under sunny skies and enjoy the scenic views along the Mekong River.
The Meteorological Department also said on Wednesday that tropical storm Yutu is moving westward from the Philippines and is expected to disperse in the upper South China Sea, and will not affect Thailand.
More rain is forecast for areas in the South.