There are three main seasons in most of Thailand: hot, cool, and rainy. The southern coasts, however, generally only have two seasons: wet and dry. These two seasons are during different months, too, depending on whether it’s the Andaman or Gulf coast.
Central, Northern, and Northeastern Thailand have similar seasons. November to May is the cool season. Despite the name, temperatures and humidity levels are still often fairly high, though conditions are generally comfortable. There is little rainfall. Temperatures are typically cooler the farther north one goes. The cool season is the prime tourist season. Prices are often higher and pre-booking may be required for accommodation and tours in popular areas.
March to May is the hot season, with temperatures that can soar to uncomfortable levels. Fewer tourist numbers mean that more bargains can be found when it comes to accommodation and activities.
May to November is the rainy season, with the wettest months usually being July and August. Travel during the rainy season can still be pleasant, as heavy rains and thunderstorms often last for just a couple of hours each day. Humidity levels are high, though. Travellers should be aware that flooding often occurs in many provinces; it is advisable to always check flood warnings before embarking on a trip. Flash floods can be especially problematic.
Gulf Coast seasons
Along the Gulf coast, the rainy season is from September to December. The rainy season along the Andaman coast is between April and October. The other months are mainly dry, hot, and sunny. Prices can be lower in the rainy season. It may not be possible to swim at times though; visitors should always check swimming advisories to avoid potentially getting into difficulties in the ocean. In some areas, fewer bars and restaurants may be open during the off-peak period, though travellers can usually always find plenty of places to choose between.