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When to go · Thailand

Thailand in September

Avoid month. Wettest month in Bangkok and on the Andaman coast; flooding in low areas. Only for low prices.

Key facts

Verdict
Avoid
Crowds
Low
Thailand
Prices
Low
Thailand

Verdict

AvoidVoykit month rating for Thailand

Wettest month in Bangkok and on the Andaman coast; flooding in low areas. Only for low prices.

Is another month better than September?

September is rated avoid. These months rate higher:

Weather in September

  • Bangkok and centre · Bangkok, Ayutthaya, Kanchanaburirainy

    Cool season Nov–Feb is the easy window; April reaches 38 °C (100 °F); September and October bring street flooding in short bursts.

  • North · Chiang Mai, Chiang Rai, Pairainy

    Cool nights Dec–Jan; the burning season (Feb–Apr) puts air quality among the worst in Asia — check AQI before booking.

  • Andaman coast · Phuket, Krabi, Koh Lanta, Khao Lakrainy

    Southwest monsoon May–Oct: rough seas, red-flag beaches, and the Similan and Surin parks closed.

  • Gulf islands · Koh Samui, Koh Phangan, Koh Taofine

    Opposite rhythm: dry and calm Feb–Sep, wettest Oct–Dec when ferries can cancel.

  • Eastern Thailand: Eastern Gulf Coast · Pattaya, Rayong, Ko Samet, Ko Changrainy

    The Gulf side takes most of its rain from May to October; November to February is the drier, cooler window and the peak for island beds.

  • Isaan: Khorat Plateau · All of Isaanrainy

    Dec–Jan days 25–30 °C (77–86 °F), nights down to about 10 °C (50 °F). Feb–Apr 30–35 °C (86–95 °F) and humid, with smoky air from cane burning. May–Aug very wet.

  • Ko Pha-ngan: Ko Pha-ngan · Gulf of Thailandrainy

    Best months Dec–Mar (dry, clear water). Jul–Aug is a secondary warm season with less rain. May–Oct is monsoon with heavy rain and rough seas.

  • Ko Samui: Ko Samui · Gulf of Thailandbest weather

    Dry season Feb–Sep; rainy season Oct–Dec with heavy downpours. Best months: Jan–Feb (dry and slightly cooler).

  • Northern Thailand: Chiang Mai and the plains · valleys and lowland citiesrainy

    Cool season Nov–Feb brings 15–20 °C (59–68 °F) nights; Mar–May is 35 °C (95 °F)+ and smoky; Jun–Oct is green with afternoon rain.

  • Northern Thailand: Hill country (Mae Hong Son, Doi Inthanon) · above about 1,000 mrainy

    Cold-season nights on the ridges can drop near freezing; bring a layer even in the hot season.

  • Southern Thailand: Andaman coast (Phuket, Krabi, Lanta, Lipe) · west-facing coastrainy

    Dry roughly Nov–Apr; May–Oct brings rain and rougher seas, and some islands and dive sites shut.

  • Southern Thailand: Gulf coast (Samui, Phangan, Tao) · east-facing coast south of Chumphonbest weather

    Driest roughly Feb–Sep; heaviest rain and wind Oct–Dec.

  • Bangkok32 °C (90 °F) / 25 °C (77 °F), 21 rain days
  • Amnat Charoen31 °C (88 °F) / 26 °C (79 °F), 7 rain days
  • Amphawa33 °C (91 °F) / 26 °C (79 °F), 13 rain days
  • Ang Thong33 °C (91 °F) / 26 °C (79 °F), 12 rain days
  • Ao Luek32 °C (90 °F) / 24 °C (75 °F), 19 rain days
  • Ao Nai Wok31 °C (88 °F) / 26 °C (79 °F), 15 rain days
  • Ao Nang31 °C (88 °F) / 24 °C (75 °F), 21 rain days
  • Aranyaprathet31 °C (88 °F) / 24 °C (75 °F), 19 rain days
  • Ban Kai31 °C (88 °F) / 25 °C (77 °F), 15 rain days
  • Ban Krut33 °C (91 °F) / 26 °C (79 °F), 12 rain days
  • Ban Phe33 °C (91 °F) / 27 °C (81 °F), 11 rain days
  • Ban Rak Thai32 °C (90 °F) / 20 °C (68 °F), 9 rain days
  • Ban Tai31 °C (88 °F) / 26 °C (79 °F), 13 rain days
  • Bang Pa‑In33 °C (91 °F) / 26 °C (79 °F), 11 rain days
  • Bang Rak32 °C (90 °F) / 25 °C (77 °F), 16 rain days
  • Bang Saen33 °C (91 °F) / 27 °C (81 °F), 11 rain days
  • Bang Thao31 °C (88 °F) / 26 °C (79 °F), 12 rain days
  • Betong32 °C (90 °F) / 26 °C (79 °F), 14 rain days
  • Bophut31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Bottle Beach32 °C (90 °F) / 25 °C (77 °F), 17 rain days
  • Buriram33 °C (91 °F) / 24 °C (75 °F), 11 rain days
  • Cape Panwa31 °C (88 °F) / 27 °C (81 °F), 13 rain days
  • Cha-am32 °C (90 °F) / 26 °C (79 °F), 11 rain days
  • Chachoengsao31 °C (88 °F) / 26 °C (79 °F), 9 rain days
  • Chai Nat34 °C (93 °F) / 26 °C (79 °F), 12 rain days
  • Chaiya32 °C (90 °F) / 26 °C (79 °F), 13 rain days
  • Chaiyaphum32 °C (90 °F) / 24 °C (75 °F), 10 rain days
  • Chalok Lam31 °C (88 °F) / 27 °C (81 °F), 9 rain days
  • Chalong Bay32 °C (90 °F) / 26 °C (79 °F), 10 rain days
  • Chaweng31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Chiang Dao31 °C (88 °F) / 22 °C (72 °F), 17 rain days
  • Chiang Khan32 °C (90 °F) / 23 °C (73 °F), 11 rain days
  • Chiang Khong31 °C (88 °F) / 23 °C (73 °F), 17 rain days
  • Chiang Rai31 °C (88 °F) / 23 °C (73 °F), 17 rain days
  • Chiang Saen31 °C (88 °F) / 23 °C (73 °F), 17 rain days
  • Choeng Mon31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Chonburi33 °C (91 °F) / 27 °C (81 °F), 13 rain days
  • Chong Mek33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Chumphon31 °C (88 °F) / 24 °C (75 °F), 18 rain days
  • Damnoen Saduak33 °C (91 °F) / 25 °C (77 °F), 18 rain days
  • Dan Chang33 °C (91 °F) / 24 °C (75 °F), 16 rain days
  • Doi Tung31 °C (88 °F) / 21 °C (70 °F), 15 rain days
  • Fang32 °C (90 °F) / 24 °C (75 °F), 13 rain days
  • Haad Chao Phao31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Haad Rin33 °C (91 °F) / 27 °C (81 °F), 10 rain days
  • Haad Salad32 °C (90 °F) / 25 °C (77 °F), 18 rain days
  • Haad Son31 °C (88 °F) / 25 °C (77 °F), 18 rain days
  • Haad Yao31 °C (88 °F) / 26 °C (79 °F), 11 rain days
  • Had Yao31 °C (88 °F) / 23 °C (73 °F), 20 rain days
  • Hang Chat32 °C (90 °F) / 22 °C (72 °F), 13 rain days
  • Hat Lek31 °C (88 °F) / 26 °C (79 °F), 12 rain days
  • Hat Yai33 °C (91 °F) / 24 °C (75 °F), 16 rain days
  • Hua Hin31 °C (88 °F) / 24 °C (75 °F), 17 rain days
  • Jom Jang32 °C (90 °F) / 24 °C (75 °F), 16 rain days
  • Jomtien31 °C (88 °F) / 25 °C (77 °F), 17 rain days
  • Kalasin34 °C (93 °F) / 24 °C (75 °F), 10 rain days
  • Kamala32 °C (90 °F) / 26 °C (79 °F), 13 rain days
  • Kamphaeng Phet32 °C (90 °F) / 24 °C (75 °F), 18 rain days
  • Kanchanaburi33 °C (91 °F) / 24 °C (75 °F), 19 rain days
  • Karon31 °C (88 °F) / 24 °C (75 °F), 22 rain days
  • Kata31 °C (88 °F) / 24 °C (75 °F), 21 rain days
  • Khanom33 °C (91 °F) / 26 °C (79 °F), 8 rain days
  • Khok Kloi32 °C (90 °F) / 26 °C (79 °F), 12 rain days
  • Khon Kaen32 °C (90 °F) / 24 °C (75 °F), 18 rain days
  • Khun Yuam31 °C (88 °F) / 22 °C (72 °F), 19 rain days
  • Ko Bulon Leh31 °C (88 °F) / 26 °C (79 °F), 13 rain days
  • Ko Kret32 °C (90 °F) / 25 °C (77 °F), 17 rain days
  • Ko Kut31 °C (88 °F) / 26 °C (79 °F), 12 rain days
  • Ko Lipe30 °C (86 °F) / 24 °C (75 °F), 19 rain days
  • Ko Mak32 °C (90 °F) / 27 °C (81 °F), 8 rain days
  • Ko Muk31 °C (88 °F) / 25 °C (77 °F), 13 rain days
  • Ko Nang Yuan31 °C (88 °F) / 25 °C (77 °F), 11 rain days
  • Ko Samet31 °C (88 °F) / 25 °C (77 °F), 15 rain days
  • Ko Sichang31 °C (88 °F) / 26 °C (79 °F), 11 rain days
  • Ko Sire31 °C (88 °F) / 24 °C (75 °F), 21 rain days
  • Ko Tao31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Krabi Town31 °C (88 °F) / 23 °C (73 °F), 21 rain days
  • Laem Chabang31 °C (88 °F) / 25 °C (77 °F), 17 rain days
  • Laem Sing33 °C (91 °F) / 27 °C (81 °F), 9 rain days
  • Laem Yai32 °C (90 °F) / 25 °C (77 °F), 16 rain days
  • Lamai31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Lampang32 °C (90 °F) / 23 °C (73 °F), 16 rain days
  • Lamphun31 °C (88 °F) / 22 °C (72 °F), 12 rain days
  • Lang Suan32 °C (90 °F) / 24 °C (75 °F), 16 rain days
  • Loei31 °C (88 °F) / 23 °C (73 °F), 19 rain days
  • Lom Sak33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Lopburi32 °C (90 °F) / 25 °C (77 °F), 17 rain days
  • Mae Hong Son32 °C (90 °F) / 22 °C (72 °F), 19 rain days
  • Mae La Noi32 °C (90 °F) / 22 °C (72 °F), 17 rain days
  • Mae Nam31 °C (88 °F) / 27 °C (81 °F), 7 rain days
  • Mae Rim31 °C (88 °F) / 22 °C (72 °F), 13 rain days
  • Mae Sai31 °C (88 °F) / 23 °C (73 °F), 16 rain days
  • Mae Salong27 °C (81 °F) / 19 °C (66 °F), 18 rain days
  • Mae Sariang31 °C (88 °F) / 23 °C (73 °F), 11 rain days
  • Mae Sot32 °C (90 °F) / 23 °C (73 °F), 20 rain days
  • Maha Sarakham34 °C (93 °F) / 25 °C (77 °F), 10 rain days
  • Mai Khao32 °C (90 °F) / 27 °C (81 °F), 12 rain days
  • Mukdahan33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Nai Han33 °C (91 °F) / 27 °C (81 °F), 10 rain days
  • Nai Thon and Nai Yang32 °C (90 °F) / 26 °C (79 °F), 12 rain days
  • Nakhon Nayok31 °C (88 °F) / 25 °C (77 °F), 12 rain days
  • Nakhon Pathom33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Nakhon Phanom33 °C (91 °F) / 25 °C (77 °F), 9 rain days
  • Nakhon Ratchasima32 °C (90 °F) / 24 °C (75 °F), 19 rain days
  • Nakhon Sawan32 °C (90 °F) / 24 °C (75 °F), 13 rain days
  • Nakhon Si Thammarat32 °C (90 °F) / 23 °C (73 °F), 17 rain days
  • Nan31 °C (88 °F) / 23 °C (73 °F), 18 rain days
  • Nang Rong34 °C (93 °F) / 25 °C (77 °F), 9 rain days
  • Narathiwat32 °C (90 °F) / 24 °C (75 °F), 13 rain days
  • Nathon31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Nong Bua Lamphu33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Nong Khai32 °C (90 °F) / 24 °C (75 °F), 16 rain days
  • Nonthaburi33 °C (91 °F) / 27 °C (81 °F), 13 rain days
  • Padang Besar33 °C (91 °F) / 26 °C (79 °F), 13 rain days
  • Pai30 °C (86 °F) / 21 °C (70 °F), 19 rain days
  • Pak Bara33 °C (91 °F) / 27 °C (81 °F), 12 rain days
  • Pak Chong33 °C (91 °F) / 25 °C (77 °F), 11 rain days
  • Pangmapha31 °C (88 °F) / 21 °C (70 °F), 18 rain days
  • Pathum Thani34 °C (93 °F) / 26 °C (79 °F), 11 rain days
  • Patong31 °C (88 °F) / 24 °C (75 °F), 19 rain days
  • Pattani31 °C (88 °F) / 24 °C (75 °F), 15 rain days
  • Phatthalung30 °C (86 °F) / 26 °C (79 °F), 13 rain days
  • Phayao31 °C (88 °F) / 23 °C (73 °F), 17 rain days
  • Phetchabun33 °C (91 °F) / 25 °C (77 °F), 9 rain days
  • Phetchaburi32 °C (90 °F) / 26 °C (79 °F), 12 rain days
  • Phichit33 °C (91 °F) / 26 °C (79 °F), 12 rain days
  • Phimai33 °C (91 °F) / 25 °C (77 °F), 12 rain days
  • Phitsanulok32 °C (90 °F) / 25 °C (77 °F), 19 rain days
  • Phon Phisai32 °C (90 °F) / 24 °C (75 °F), 15 rain days
  • Phrae30 °C (86 °F) / 24 °C (75 °F), 7 rain days
  • Phuket Town32 °C (90 °F) / 25 °C (77 °F), 22 rain days
  • Prachinburi32 °C (90 °F) / 26 °C (79 °F), 8 rain days
  • Prachuap Khiri Khan31 °C (88 °F) / 24 °C (75 °F), 18 rain days
  • Rai Leh31 °C (88 °F) / 23 °C (73 °F), 21 rain days
  • Rangsit33 °C (91 °F) / 26 °C (79 °F), 13 rain days
  • Ranong31 °C (88 °F) / 23 °C (73 °F), 23 rain days
  • Ratchaburi33 °C (91 °F) / 26 °C (79 °F), 11 rain days
  • Rawai33 °C (91 °F) / 27 °C (81 °F), 11 rain days
  • Roi Et31 °C (88 °F) / 24 °C (75 °F), 18 rain days
  • Sadao33 °C (91 °F) / 25 °C (77 °F), 13 rain days
  • Sakon Nakhon31 °C (88 °F) / 23 °C (73 °F), 17 rain days
  • Samoeng31 °C (88 °F) / 24 °C (75 °F), 11 rain days
  • Samut Prakan33 °C (91 °F) / 27 °C (81 °F), 12 rain days
  • Samut Sakhon32 °C (90 °F) / 26 °C (79 °F), 9 rain days
  • Samut Songkhram34 °C (93 °F) / 26 °C (79 °F), 16 rain days
  • Sangkhla Buri31 °C (88 °F) / 23 °C (73 °F), 20 rain days
  • Saraburi32 °C (90 °F) / 25 °C (77 °F), 19 rain days
  • Sathing Phra33 °C (91 °F) / 25 °C (77 °F), 10 rain days
  • Satun31 °C (88 °F) / 24 °C (75 °F), 18 rain days
  • Si Racha32 °C (90 °F) / 24 °C (75 °F), 16 rain days
  • Si Satchanalai33 °C (91 °F) / 26 °C (79 °F), 10 rain days
  • Sing Buri33 °C (91 °F) / 26 °C (79 °F), 11 rain days
  • Sisaket31 °C (88 °F) / 25 °C (77 °F), 7 rain days
  • Songkhla31 °C (88 °F) / 27 °C (81 °F), 11 rain days
  • Sri Thanu31 °C (88 °F) / 25 °C (77 °F), 16 rain days
  • Sukhothai32 °C (90 °F) / 24 °C (75 °F), 18 rain days
  • Sungai Kolok33 °C (91 °F) / 25 °C (77 °F), 11 rain days
  • Suphanburi33 °C (91 °F) / 25 °C (77 °F), 18 rain days
  • Surat Thani31 °C (88 °F) / 24 °C (75 °F), 18 rain days
  • Surin, Southern Thailand31 °C (88 °F) / 24 °C (75 °F), 22 rain days
  • Surin32 °C (90 °F) / 24 °C (75 °F), 19 rain days
  • Tak Bai32 °C (90 °F) / 25 °C (77 °F), 12 rain days
  • Tak31 °C (88 °F) / 24 °C (75 °F), 13 rain days
  • Takua Pa31 °C (88 °F) / 24 °C (75 °F), 19 rain days
  • Thaton31 °C (88 °F) / 22 °C (72 °F), 17 rain days
  • Thong Nai Pan32 °C (90 °F) / 26 °C (79 °F), 7 rain days
  • Thong Sala31 °C (88 °F) / 26 °C (79 °F), 8 rain days
  • Thonglang Bay32 °C (90 °F) / 25 °C (77 °F), 15 rain days
  • Ton Sai31 °C (88 °F) / 27 °C (81 °F), 13 rain days
  • Trat32 °C (90 °F) / 26 °C (79 °F), 12 rain days
  • Ubon Ratchathani31 °C (88 °F) / 24 °C (75 °F), 19 rain days
  • Udon Thani32 °C (90 °F) / 24 °C (75 °F), 17 rain days
  • Umphang32 °C (90 °F) / 23 °C (73 °F), 18 rain days
  • Uthai Thani33 °C (91 °F) / 27 °C (81 °F), 9 rain days
  • Uttaradit33 °C (91 °F) / 25 °C (77 °F), 10 rain days
  • Yala31 °C (88 °F) / 25 °C (77 °F), 18 rain days
  • Yasothon33 °C (91 °F) / 25 °C (77 °F), 9 rain days
  • Chiang Mai31 °C (88 °F) / 24 °C (75 °F), 19 rain days
  • Phuket30 °C (86 °F) / 24 °C (75 °F), 21 rain days
  • Pattaya31 °C (88 °F) / 25 °C (77 °F), 18 rain days

Festivals and holidays

Dates as our data lists them. Moving holidays (lunar and Islamic calendars, Easter) shift every year: check the date for your year before you build a trip on it.

  • Phuket Vegetarian Festival

    Sep–Oct (9 days, lunar)

    Street processions with piercings in Phuket Town; road closures and firecrackers.

  • Vegetarian (Jay) Festival check

    First nine days of the 9th Chinese lunar month · Bangkok

    Yellow flags mark meat-free stalls; Chinatown classics in vegan versions.

Crowds and prices

Crowds · Thailand
Low
Prices · Thailand
Low

Compare two months

Weather, crowds and prices for any two months in Thailand, side by side.

  • Verdict

    Sep: Avoid

    Jan: Great (better)

  • Crowds

    Sep: Low

    Jan: High

  • Prices

    Sep: Low

    Jan: High

  • Festivals listed

    Sep: 2

    Jan: 3

September: Wettest month in Bangkok and on the Andaman coast; flooding in low areas. Only for low prices.

January: Cool and dry nearly everywhere: the easiest month; book islands and Chiang Mai early.

Thailand: figures are long-term averages from this guide, not a forecast.

What to pack

  • A rain jacket or umbrella and shoes that dry fast

Build the full packing list for your trip →

Where to go in September

Rated best or good this month

  • Ao Nai Wok

    Best months: Feb–Sep

  • Ban Kai

    Best months: Feb–Sep (dry season on the Gulf coast)

  • Ban Tai

    Best months: Feb–Sep

  • Bang Rak

    Best months: Feb–Sep

  • Bang Saen

    Best months: Feb–Sep (check)

  • Bottle Beach

    Best months: Feb–Sep

  • Chalok Lam

    Best months: Feb–Sep

  • Chaweng

    Best months: Feb–Sep (Gulf coast dry season); Dec–Jan can bring rain and rough water

  • Choeng Mon

    Best months: Feb–Sep (Gulf coast dry season)

  • Chumphon

    Best months: Feb–Sep (Gulf dry season)

  • Haad Chao Phao

    Best months: Feb–Sep

  • Haad Rin

    Best months: Feb–Sep (dry season, many full moons)

Better another month

  • Bangkok

    Wettest month; street flooding in low areas after storms.