SeasonMapThailand in September
September is Thailand's weakest month (rank 12 of 12): its 19 destinations average 58/100, led by Ko Samui at 71 — 34°C and 22 rainy days — while Ko Tao is cooler at 27°C and scores 67.
#12 of 12 months for Thailand · 19 destinations · updated September 2026 · climate normals from ERA5 reanalysis
Where in Thailand in September
| # | Place | Type | Feels-like high | Rain | Comfort | At its best |
|---|---|---|---|---|---|---|
| 1 | Ko Samui | Island | 34°C | 158 mm · 22 days | 71 tier B | — |
| 2 | Ko Lipe | Island | 28°C | 239 mm · 22 days | 67 tier C | — |
| 3 | Ko Pha Ngan | Island | 28°C | 201 mm · 22 days | 67 tier C | — |
| 4 | Ko Tao | Island | 27°C | 206 mm · 23 days | 67 tier C | — |
| 5 | Ko Phi Phi | Island | 28°C | 264 mm · 22 days | 63 tier C | — |
| 6 | Hua Hin | Beach | 30°C | 220 mm · 25 days | 62 tier C | — |
| 7 | Ko Lanta | Island | 28°C | 292 mm · 24 days | 61 tier C | — |
| 8 | Pattaya | Beach | 36°C | 276 mm · 26 days | 60 tier C | — |
| 9 | Krabi | Beach | 35°C | 309 mm · 25 days | 58 tier D | — |
| 10 | Phuket | Beach | 33°C | 301 mm · 23 days | 58 tier D | — |
| 11 | Khao Lak | Beach | 29°C | 340 mm · 24 days | 56 tier D | — |
| 12 | Pai | Trekking hub | 35°C | 250 mm · 26 days | 56 tier D | — |
| 13 | Chiang Mai | City | 36°C | 237 mm · 23 days | 53 tier D | — |
| 14 | Kanchanaburi | City | 31°C | 210 mm · 23 days | 53 tier D | — |
| 15 | Chiang Rai | City | 30°C | 258 mm · 24 days | 52 tier D | — |
| 16 | Khao Sok | National park | 29°C | 344 mm · 26 days | 49 tier F | — |
| 17 | Ko Chang | Island | 29°C | 548 mm · 29 days | 49 tier F | — |
| 18 | Bangkok | City | 37°C | 267 mm · 26 days | 48 tier F | — |
| 19 | Ayutthaya | City | 31°C | 293 mm · 26 days | 44 tier F | — |
Comfort is SeasonMap's 0–100 score; each place is judged through the lens that suits it — beaches on beach weather, ski resorts on snow. "At its best" means September is one of that place's own top three months. Feels-like highs fold in humidity, wind and sun.
What's on in Thailand in September
- Full Moon Party · Ko Pha Ngan · 1 Jan – 31 Dec
- Waterfalls at full flow · Chiang Mai · 1 Aug – 15 Oct (usually)
- Erawan falls at full flow · Kanchanaburi · 15 Sep – 31 Dec (usually)