The best time to visit Thailand is during the cool, dry season from November through February, when temperatures are milder, humidity is lower, and rainfall is at its lowest across most of the country.
Thailand’s Three Seasons
Thailand’s climate breaks into three distinct stretches: a cool, dry season from November to February, a hot season from March to May, and a rainy monsoon season from roughly June through October. The exact timing shifts somewhat between the northern mainland and the southern islands, since Thailand’s two coastlines, the Gulf of Thailand and the Andaman Sea, follow slightly different monsoon patterns.
Phuket Weather by Month
The chart below shows average high and low temperatures, monthly rainfall, and sea temperature for Phuket and the Andaman coast. Gulf coast islands like Koh Samui follow a different pattern, staying driest around December-January.
Jan
(90°/75°F)
3 rainy days
Sea Temp. 29°C
Feb
(91°/77°F)
3 rainy days
Sea Temp. 29°C
Mar
(91°/77°F)
6 rainy days
Sea Temp. 30°C
Apr
(91°/79°F)
10 rainy days
Sea Temp. 30°C
May
(90°/77°F)
18 rainy days
Sea Temp. 29°C
Jun
(88°/77°F)
18 rainy days
Sea Temp. 29°C
Jul
(88°/75°F)
19 rainy days
Sea Temp. 28°C
Aug
(88°/75°F)
20 rainy days
Sea Temp. 28°C
Sep
(86°/75°F)
21 rainy days
Sea Temp. 28°C
Oct
(86°/75°F)
20 rainy days
Sea Temp. 28°C
Nov
(86°/75°F)
12 rainy days
Sea Temp. 28°C
Dec
(88°/75°F)
6 rainy days
Sea Temp. 28°C
| Month | Avg. High | Avg. Low | Rainfall | Rainy Days | Sea Temp. |
|---|---|---|---|---|---|
| Jan | 32°C / 90°F | 24°C / 75°F | 35 mm | 3 | 29°C |
| Feb | 33°C / 91°F | 25°C / 77°F | 40 mm | 3 | 29°C |
| Mar | 33°C / 91°F | 25°C / 77°F | 70 mm | 6 | 30°C |
| Apr | 33°C / 91°F | 26°C / 79°F | 120 mm | 10 | 30°C |
| May | 32°C / 90°F | 25°C / 77°F | 260 mm | 18 | 29°C |
| Jun | 31°C / 88°F | 25°C / 77°F | 250 mm | 18 | 29°C |
| Jul | 31°C / 88°F | 24°C / 75°F | 260 mm | 19 | 28°C |
| Aug | 31°C / 88°F | 24°C / 75°F | 260 mm | 20 | 28°C |
| Sep | 30°C / 86°F | 24°C / 75°F | 350 mm | 21 | 28°C |
| Oct | 30°C / 86°F | 24°C / 75°F | 320 mm | 20 | 28°C |
| Nov | 30°C / 86°F | 24°C / 75°F | 140 mm | 12 | 28°C |
| Dec | 31°C / 88°F | 24°C / 75°F | 60 mm | 6 | 28°C |
Cool Season (November-February): The Best All-Around Window
This is peak tourist season for good reason: lower humidity, comfortable temperatures, and minimal rain make it ideal for both city sightseeing in Bangkok and Chiang Mai and beach time on islands like Phuket and Koh Samui. Expect higher prices and busier attractions during this stretch, especially around the December-January holidays.
Hot Season (March-May): Intense Heat Before the Rains
March through May brings the year’s highest temperatures, often exceeding 35 degrees Celsius (95 Fahrenheit) in central Thailand, with high humidity making it feel even hotter. It is a quieter, cheaper time to visit if you can handle the heat, and coastal areas benefit from sea breezes that make the temperature more bearable than inland cities.
Rainy Season (June-October): Not Always a Dealbreaker
The monsoon typically brings heavy but often short afternoon downpours rather than all-day rain, and destinations on the Gulf coast, like Koh Samui, actually see their driest stretch later in the year, around December-January, due to a different monsoon pattern than the Andaman coast. Traveling during the rainy season means lower prices and fewer crowds, with many days still offering plenty of sunshine between showers.
Tracking Rain Around Your Itinerary
Because Thailand’s rainy-season showers tend to be intense but brief, checking a live rain map before heading out can help you time activities around a passing storm rather than canceling plans altogether, an approach covered in more detail in our guide to using rain radar to plan outdoor events. For a Phuket-specific view, check the live rain radar for Phuket.
Frequently Asked Questions
What is the best month to visit Thailand?
December through February is the most reliable window nationwide: cool, dry, and comfortable, with warm days and none of the peak humidity of the hot season.
What is the rainiest month in Thailand?
On the Andaman coast (Phuket, Krabi), September is wettest with around 350mm of rain across 21 rainy days; the Gulf coast (Koh Samui) instead peaks in October-November due to a different monsoon pattern.
Is Thailand too hot in April?
April is Thailand’s hottest month nationwide, with highs regularly topping 35C (95F) in central and northern regions, though coastal areas are tempered somewhat by sea breezes.
Can you visit Thailand during the rainy season?
Yes. Rain typically falls as heavy but short afternoon downpours rather than all-day rain, and the rainy season brings lower prices, fewer crowds, and lush green scenery.
Is Koh Samui’s weather different from Phuket?
Yes, significantly. Koh Samui sits on the Gulf of Thailand and has its wettest months in October-November, while Phuket sits on the Andaman Sea and is wettest around September, an important distinction when planning a coastal trip.
What is the cheapest time to visit Thailand?
The rainy season, roughly June through October, generally has the lowest hotel and flight prices, since it falls outside the peak cool-season demand.
In Conclusion
For the most comfortable all-around trip, November through February is hard to beat. But Thailand’s rainy season is not necessarily a reason to avoid it, especially if you plan around the daily shower pattern rather than the season’s reputation.
