Thailand
Hot Season: March-May (Avg. High 90sF)
Cool Season: Nov-Feb (Avg. 78F)
Rainy Season: April-November
Thailand has two distinct climate zones: tropical in the south and tropical savanna in the north.
The northern, and central areas of the country (Bangkok, Chiang Mai, Chiang Rai) experience three distinct seasons.
The hot season from March to May, brings temperatures averaging in the upper 90sF and sporadic rain.
The cool season, from November to February, has temperatures around 80F with infrequent showers. Daily temperatures can drop as low as 60F in Chiang Mai and 41F in the hills.
The rainy season, from April to November, brings average temperatures of around 84F and 90% humidity. While heavy downpours are common, all-day rain is quite rare. Trekking in the north is not recommended in June, when floods are more likely. 
The Southern Thai Peninsula (Phuket or Koh Samui) has intermittent showers year-round, but daily downpours during the rainy season. Temperatures average in the low 80sF. Optimal weather on Phuket occurs between November and April, when the island welcomes the highest numbers of travelers. Koh Samui's high season is from Feb. to Oct.

* Sample prices displayed include international and domestic airline tickets as per itinerary and ALL airline-related taxes and fuel surcharges and are per person, based on double occupancy, and are dynamic in nature. Prices do not include insurance or delivery charges which are optional and customizable by the traveler. The airfare portion of the itinerary price is based on economy class, midweek departure. Prices do not include fees for carry on or checked baggage which can add additional fees per ticket on a roundtrip flight based on carrier charges. It also does not include any entrance fees or visa fees that may be charged at international airports. Some cities may charge local taxes that can only be collected by hotel at destination.
Prices were accurate at the time we posted them. Sample prices were for a specific travel date and specific departure airport, as indicated. Your prices will vary according to departure cities and travel dates. We do not control prices (airlines and hotel reservation systems do). Prices may change dynamically and at times significantly numerous times during any given day.
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