The Thai Meteorological Department (TMD) announced that Thailand has entered the hot season on Sunday, February 22, 2026.
The hot season generally runs from late February to mid-May, before the gradual onset of the southwest monsoon.
The TMD forecasts an alternation between intense heat and violent storms, with peaks that can exceed 42 °C in certain provinces.
The highest temperatures are expected between April and May 2026, traditionally the hottest period of the year.
The average maximum temperature in northern Thailand is expected to reach 36-37 °C, slightly higher than the usual average of 35.4 °C and a slight increase compared to the previous year (the average maximum temperature in 2025 was 35.8 °C).
Overall, rainfall is expected to be 30-40% lower than normal levels.
The provinces expected to experience temperatures above 42 °C are as follows:
- Mae Hong Son
- Lampang
- Tak
What to expect for summer 2026 in Thailand
Intense sun in an orange sky
From March to mid-April
Hot temperatures will gradually rise, with heatwave conditions in many regions during the day.
Fog will appear in several regions, while the north and northeast will still experience cool mornings due to the influence of high-pressure systems from China.
However, between the end of March and mid-April, these pressures will weaken and low-pressure systems caused by heat will dominate, leading to periods of hot and humid weather, with temperatures reaching 42 to 43 °C in some regions.
Summer storms are also expected in these regions, with thunder, gusty winds, and even hail in some areas, bringing temporary relief from the heat.
Late April to mid-May
As the season changes, hot conditions will continue, with occasional relief in the form of showers.
At this time, southeast winds bringing moisture from the Gulf of Thailand will change direction, marking the beginning of the southwest monsoon.
This change will bring more rainfall, especially in the southern provinces, which will experience heavy rain and stronger winds.
From March to the end of April, easterly and southeasterly winds will cover the Gulf of Thailand and the southern regions, leading to a 20 to 30% chance of thunderstorms.
The waters of the Gulf of Thailand and the Andaman Sea will experience waves reaching up to 1 meter high.
South Thailand
From mid-April to mid-May, rainfall will increase significantly, with some areas experiencing intense showers, particularly along the southwestern coast, where rainfall could cover 60 to 80% of the area.
The Andaman Sea will experience stronger winds and waves reaching 2 to 3 meters, while the Gulf of Thailand will see waves reaching 1 to 2 meters as the southwest monsoon sets in.
Source: The Nation Thailand
