Photo: Andre Mouton / Pexels
Heavy rain is hitting 29 provinces in Thailand today, 13 October 2026, with the Central region, the East and the upper South affected most. The Thai Meteorological Department (TMD) forecasts scattered thundershowers with isolated heavy rain across the country. Koh Lanta sits in Krabi province, so expect showers, possible downpours and rough seas. Boat trips may be disrupted, and flash floods are possible near hills and streams.
What is driving the weather
Three systems are behind today's rain:
- A high-pressure system from China covers upper Thailand and the South China Sea. It pushes easterly and southeasterly winds that carry moisture into the upper country.
- A monsoon trough lies across the lower South.
- The southwest monsoon prevails over the Andaman Sea, adding rain in the South.
How the past few days compare
Today's 29 provinces on heavy rain alert follow a wet few days:
- 11 October: heavy rain in 33 provinces, including heavy rain in Bangkok.
- 12 October: heavy rain in 9 provinces, with a few showers in Bangkok.
Regional forecast
Every region is forecast to see scattered thundershowers and isolated heavy rain.
| Region | Areas named | Low (°C) | High (°C) | Wind |
|---|---|---|---|---|
| Bangkok | Capital | 25-26 | 33-35 | SE, 10-20 km/h |
| North | Kamphaeng Phet | 20-25 | 33-36 | E, 10-20 km/h |
| Northeast | Nakhon Ratchasima, Surin | 22-25 | 32-33 | E, up to 25 km/h |
| Central | Nakhon Sawan, Uthai Thani, Chai Nat, Sing Buri, Ang Thong, Suphan Buri, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon, Samut Songkhram | 23-25 | 33-34 | SE, 10-20 km/h |
| East | Nakhon Nayok, Prachin Buri, Sa Kaeo, Chon Buri, Rayong, Chanthaburi, Trat | 23-25 | 32-35 | SE, up to 30 km/h |
| South, east coast | Phetchaburi, Prachuap Khiri Khan, Surat Thani, Yala, Narathiwat | 24-25 | 32-33 | Variable, up to 30 km/h |
| South, west coast | Phang Nga, Phuket, Krabi | 23-25 | 31-34 | Variable, up to 30 km/h |
Sea conditions
- East coast of the South and the East: waves are below 1 m in general, and above 2 m in thundershowers.
- West coast of the South: waves reach about 1 m, and above 2 m in thundershowers.
- Andaman Sea and the Gulf: waves exceed 2 m in thundershower areas.
Ships should steer clear of thundershowers.
Warnings
The TMD warns people to beware of heavy rain and accumulations. Flash floods and overflows are possible, especially along waterways near foothills and lowlands.
What this means for visitors
- Andaman coast (Phuket, Krabi, Phang Nga): expect showers and possible heavy downpours, with highs of 31-34°C. Koh Lanta is in Krabi province, so it falls in this zone.
- Boat trips and ferries: waves above 2 m in thundershowers, plus the instruction for ships to avoid storm cells, mean delays or cancellations are likely. Check with operators before island-hopping or taking speedboats.
- Flash floods: low-lying areas and spots near hills and streams carry the highest risk. Avoid waterside walks and trails after heavy rain.
- Bangkok: heavy rain is likely, with possible street flooding, so allow extra travel time.
- Planning: the same rainy pattern has run for several days (11-13 October), so keep indoor backup plans.
Information sourced from The Thaiger.