Weather agency forecasts rain over 60% of East and South on October 23
Southern Thailand faces flash flood risks from heavy rain, while Bangkok expects thundershowers and gusts until 6am on October 24
- The Thai Meteorological Department forecasts thundershowers will cover 60% of eastern Thailand and both southern coasts on October 23.
- The forecast includes warnings of isolated heavy rain, with residents in the South cautioned about potential flash floods and run-off from accumulated rainfall.
- The weather is attributed to a monsoon trough over the Gulf of Thailand and a high-pressure system pushing moist southeasterly winds into the regions.
- Bangkok and its surrounding provinces are also expected to experience 60% thundershower coverage, while other parts of upper Thailand will see less rain but may have strong wind gusts.
The Thai Meteorological Department (TMD) forecasts thundershowers over 60% of eastern Thailand and both southern coasts for October 23, 2026, with isolated heavy rain, while parts of upper Thailand face strong wind gusts. The forecast covers the period from 6am on October 23 to 6am on October 24.
Southern residents should beware of heavy rain, strong gusts and accumulated rainfall that could trigger flash floods and rapid run-off near foothills and in low-lying areas, the TMD warned.
Monsoon trough crosses the Gulf and central southern Thailand
A monsoon trough lies across the Gulf of Thailand and the central part of the South, while a high-pressure system, or cold air mass, covers the upper North, upper Northeast and South China Sea.
The TMD explained that the high-pressure system is bringing southeasterly winds that carry moisture from the South China Sea and Gulf of Thailand into the lower Northeast, lower Central region, including Bangkok and surrounding provinces, and the East.
Regional thundershower coverage ranges from 10% to 60%
The TMD’s October 23–24 outlook puts thundershower coverage at 10% in the North and Northeast, rising to 40% in the Central region and 60% in the East, both southern coasts and Bangkok and surrounding provinces.
North: Thundershowers and isolated strong gusts are forecast mainly in Mae Hong Son, Phitsanulok, Tak, Kamphaeng Phet, Phichit and Phetchabun. Minimum temperatures will range from 21–26°C and maximum temperatures from 34–37°C, with easterly winds of 10–20 km/h.
Northeast: Thundershowers and isolated strong gusts are expected mainly in Chaiyaphum, Nakhon Ratchasima, Buri Ram, Surin, Si Sa Ket and Ubon Ratchathani. Minimum temperatures will be 22–25°C and maximum temperatures 33–35°C, with northeasterly winds of 10–20 km/h.
Central region: Thundershowers and isolated strong gusts are forecast mainly in Lop Buri, Saraburi, Phra Nakhon Si Ayutthaya, Kanchanaburi and Ratchaburi. Minimum temperatures will range from 23–26°C and maximum temperatures from 34–36°C, with easterly winds of 10–20 km/h.
East: Thundershowers, isolated heavy rain and strong gusts are forecast in Nakhon Nayok, Prachin Buri, Chon Buri, Rayong, Chanthaburi and Trat. Minimum temperatures will be 23–26°C and maximum temperatures 32–35°C, with southeasterly winds of 10–30 km/h.
South’s east coast: Thundershowers and isolated heavy rain are expected in Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala and Narathiwat, with minimum temperatures of 23–25°C and maximum temperatures of 32–35°C. Winds will be easterly at 15–30 km/h from Surat Thani northwards and southeasterly at the same speeds from Nakhon Si Thammarat southwards.
South’s west coast: Thundershowers and isolated heavy rain are forecast in Ranong, Phang Nga, Phuket, Krabi, Trang and Satun. Minimum temperatures will range from 24–25°C and maximum temperatures from 32–36°C, with northwesterly winds of 15–30 km/h.
Bangkok and surrounding provinces: Thundershowers and isolated strong gusts are expected, with minimum temperatures of 25–27°C and maximum temperatures of 33–36°C. Southeasterly winds will reach 10–20 km/h.
Andaman and Gulf waves could exceed two metres in thundershowers
Waves in the Andaman Sea and Gulf of Thailand could exceed two metres in areas experiencing thundershowers during the October 23–24 forecast period, the TMD warned. Mariners should navigate cautiously and avoid sailing through thundershowers.
Outside thundershowers, the TMD forecasts waves below one metre off the East and around one metre along both southern coasts.
