Climate
Most of Thailand has a "tropical wet and dry or savanna climate" type (Köppen's Tropical savanna climate).[83] The south and the eastern tip of the east have a tropical monsoon climate.
Countrywide, temperatures normally range from an average annual high of 38 °C (100.4 °F) to a low of 19 °C (66.2 °F). During the dry season, the temperature rises dramatically in the second half of March, spiking to well over 40 °C (104 °F) in some areas by mid-April when the sun passes its zenith.
Southwest monsoons that arrive between May and July (except in the south) signal the advent of the rainy season (ruedu fon). This lasts into October and the cloud covering reduces the temperature again, with the high humidity experienced as 'hot and sticky'. November and December mark the onset of the dry season and night temperatures on high ground can occasionally drop to a light frost. Temperatures begin to climb again in January.