Climate
- Tropical monsoonal climate.
The average temperature : around 29 degree Celsius
The highest temperature : 30 to 35 degree Celsius
The lowest temperature : 24 to 27 degree Celsius in Bangkok
14 to 24 degree Celsius in Chiangmai in the North
Usually, you'll hear like the above, but ...
From November to January, it gets cool or cold even in Thailand. Around this season, it's kind of cool in Bangkok but the northern part like Chiang Mai, sometimes under 10 degree Celsius early morning, and if you visit a northern mountain like Doi Inthanon, the temperature can be under zero, (they say from -8 to 22 degrees Celsius) and the average is 12 degrees through the year. Even though Thailand is a hot country, be careful not to catch a cold !
- The humidity : 70 to 80 percent
Dry or rainy season
Mainly 3 seasons.
(My wife from Thailand often says jokingly like, Thailand has three seasons; Hot, Hotter, Hottest. :-D)
Dry season (November to February)
A lot of comfortable and fine days in this season.
But the area close to Gulf of Thailand in the south is exceptional. Around November to December, the amount of rain in this area is highest. If you'd like to visit the Southern area, February to April might be the best season.
Hot season (March to May)
Even at night, the temperature doesn't go down, and it's hot from early morning.
In the latter half of this season, sudden showers in everyday.
Rainy season (June to October)
It rains and stops, rains and stops. Not means rain all day.
Climate in Bangkok
It's hottest in April. The average temperature is 30 degree but around 40 degree when it's the hottest.
The famous festival, Songkran Festival (or Water Festival) is held in this period.
The average temperature in December: around 25 degree.