Photo: Dibakar Roy / Pexels
Heavy rain is forecast across 49 provinces in Thailand on 26 October 2026, with the South and the Andaman west coast hit hardest. Koh Lanta sits in Krabi province, which is listed for fairly widespread thundershowers and isolated heavy rain. Nearby Trang and Satun get isolated very heavy rain. Expect highs of 28-33°C, northwest winds and rough seas, so boat trips may be disrupted.
What's happening
The Thai Meteorological Department (TMD) announced its daily forecast on 26 October 2026. Heavy rain is expected in 49 provinces. The South and its west coast are hit hardest, and the North, Northeast, Central and East regions also get rain.
Very heavy rain is expected in Nakhon Si Thammarat, Phatthalung, Songkhla, Surat Thani, Satun and Trang.
Why it's raining
Two weather systems are behind this:
- A high-pressure system from China extends over the upper country and the South China Sea. It pushes easterly winds that carry moisture to the upper country and upper South.
- A monsoon trough across the middle South is strengthening. It is driving continuous heavy to very heavy rain there.
Andaman coast (including Koh Lanta)
| Area | Conditions | Low | High | Wind |
|---|---|---|---|---|
| South (west coast) | Fairly widespread thundershowers, isolated heavy rain | 23-24°C | 28-33°C | NW 15-30 km/h |
- Ranong, Phang Nga, Phuket and Krabi get fairly widespread thundershowers and isolated heavy rain.
- Trang and Satun get isolated very heavy rain.
- Waves are 1-2 m, and above 2 m in thundershowers.
What it means if you're on Koh Lanta
- Boat trips, island hopping and ferries may be disrupted. Ships in the Andaman Sea and the Gulf are advised to steer clear of thundershowers.
- Flash floods, overflows and landslides are possible, especially along waterways near foothills and lowlands. Be careful on roads and near water.
- The rain is a clear step up from the previous two days, so check the daily TMD forecast.
The rest of the country
| Region | Conditions | Low | High | Wind |
|---|---|---|---|---|
| Bangkok | Scattered thundershowers, gusts, isolated heavy rain | 24-27°C | 33-35°C | SE 10-20 km/h |
| North | Scattered thundershowers, gusts, isolated heavy rain | 21-26°C | 34-36°C | SE 10-20 km/h |
| Northeast | Scattered thundershowers, gusts, isolated heavy rain | 22-24°C | 34-35°C | E 10-20 km/h |
| Central | Scattered thundershowers, gusts, isolated heavy rain | 24-27°C | 34-36°C | SE 10-20 km/h |
| East | Scattered thundershowers, gusts, isolated heavy rain | 23-25°C | 33-35°C | SE 10-30 km/h |
| South (east coast) | Scattered thundershowers, isolated heavy rain | 23-24°C | 30-34°C | Variable 15-30 km/h |
- Bangkok: expect gusty showers and isolated heavy rain. Carry rain gear and allow extra travel time.
- South east coast (Gulf side): Phetchaburi, Chumphon, Pattani, Yala and Narathiwat get scattered thundershowers and isolated heavy rain. Surat Thani, Nakhon Si Thammarat, Phatthalung and Songkhla get isolated very heavy rain. Waves are 1-2 m, above 2 m in thundershowers.
- East: Nakhon Nayok, Prachin Buri, Chachoengsao, Chon Buri, Rayong and Chanthaburi are covered. Waves are below 1 m, and above 2 m in thundershowers.
- North: Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan, Uttaradit, Sukhothai, Tak, Kamphaeng Phet, Phitsanulok and Phetchabun.
- Northeast: Loei, Khon Kaen, Maha Sarakham, Chaiyaphum, Nakhon Ratchasima, Buri Ram and Surin.
- Central: Nakhon Sawan, Uthai Thani, Lop Buri, Saraburi, Ayutthaya, Suphan Buri, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon and Samut Songkhram.
Official warnings
- People in the South should beware of heavy to very heavy rain, which may cause flash floods, overflows and landslides.
- In the upper country, avoid outdoor spaces, large trees and unsecured billboards during severe conditions.
- Ships in the Andaman Sea and the Gulf should steer clear of thundershowers.
A sharp escalation
The number of provinces with heavy rain has jumped quickly: 11 on 24 October, 19 on 25 October and 49 on 26 October.
Information sourced from The Thaiger.