TMD forecasts rain across 80% of central and eastern Thailand on Sept 26

The Thai Meteorological Department (TMD) has forecast thunderstorms across 80% of the Central and Eastern regions on Saturday (September 26), with heavy to very heavy rain also expected in Bangkok and surrounding provinces. The forecast issued at 11pm Thai time on Friday (September 25) warns that downpours and accumulated rainfall could trigger flash floods, rapid run-off and landslides. 

The TMD expects heavy rain in many areas of the North, Northeast, Central region, including Bangkok and surrounding provinces, East and upper South, with very heavy rain in some locations.

Residents on foothill slopes near waterways and in low-lying areas face particular risks from accumulated rainfall, the TMD warned. The department’s advice on flash-flood risks includes avoiding routes repeatedly affected by flooding, particularly low-lying roads where water may accumulate over short periods. 

Low-pressure system moves over Bangkok

A strong low-pressure system has moved from eastern Thailand along the monsoon trough to cover the lower Central region, including Bangkok and surrounding provinces, according to the TMD.

The southwesterly monsoon over the Andaman Sea, southern Thailand and the Gulf of Thailand is also strengthening from moderate intensity, contributing to the wet conditions, the TMD reported.

Central and Eastern regions face 80% thunderstorm coverage

The TMD forecasts thunderstorms across 80% of both the Central and Eastern regions on September 26, with heavy to very heavy rain affecting many locations. The regional outlook covers midnight at the start of September 26 until midnight at the start of September 27.

North: The TMD’s September 26 forecast puts thunderstorm coverage at 60%, with isolated heavy rain in Mae Hong Son, Chiang Mai, Lamphun, Lampang, Uttaradit, Sukhothai, Kamphaeng Phet, Phichit, Tak and Phitsanulok, and isolated very heavy rain in Phetchabun. Minimum temperatures are forecast at 22–26°C and maximum temperatures at 31–35°C, with easterly winds of 10–20km/h.

Northeast: Thunderstorms are expected across 70% of the region on September 26, according to the TMD, with isolated heavy rain in Loei, Nong Bua Lamphu, Khon Kaen, Kalasin, Maha Sarakham, Roi Et, Surin and Si Sa Ket. Chaiyaphum, Nakhon Ratchasima and Buri Ram could experience isolated very heavy rain. Minimum temperatures are forecast at 22–25°C and maximum temperatures at 27–33°C, with northeasterly winds of 10–25km/h.

Central region: The TMD forecasts thunderstorms across 80% of the region on September 26, with heavy to very heavy rain in many areas of Nakhon Sawan, Uthai Thani, Chai Nat, Sing Buri, Ang Thong, Lop Buri, Saraburi, Suphan Buri, Phra Nakhon Si Ayutthaya, Kanchanaburi, Nakhon Pathom, Ratchaburi, Samut Sakhon and Samut Songkhram. Minimum temperatures are expected at 22–25°C and maximum temperatures at 28–32°C, with variable winds of 10–25km/h.

East: Thunderstorms are forecast across 80% of the region on September 26, with heavy rain in many areas, according to the TMD. Isolated very heavy rain is possible in Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Chon Buri, Rayong, Chanthaburi and Trat. Minimum temperatures are expected at 22–24°C and maximum temperatures at 26–29°C, with variable winds of 20–40km/h; waves along the eastern coast are forecast at 2–3 metres, exceeding 3 metres in thunderstorms.

South, east coast: The TMD expects thunderstorms across 70% of the region on September 26, with isolated heavy rain in Prachuap Khiri Khan, Chumphon and Surat Thani, and isolated very heavy rain in Phetchaburi. Minimum temperatures are forecast at 21–25°C and maximum temperatures at 27–35°C.

South, west coast: Thunderstorms are forecast across 40% of the region on September 26, mainly in Ranong, Phang Nga and Phuket, according to the TMD. Minimum temperatures are expected at 23–26°C and maximum temperatures at 31–36°C.

Bangkok and surrounding provinces: The TMD forecasts thunderstorms across almost the entire metropolitan area on September 26, with heavy to very heavy rain in many locations. Minimum temperatures are expected at 23–24°C and maximum temperatures at 29–31°C, with variable winds of 10–25km/h.

Upper Gulf boats advised to stay ashore through September 27

Small boats in the upper Gulf of Thailand should remain ashore through September 27, the TMD advised, with waves forecast at 2–3 metres. Mariners throughout the Gulf and Andaman Sea should navigate cautiously and avoid thunderstorms.
For the southern Gulf coast on September 26, the TMD forecasts northwesterly winds of 20–35km/h from Surat Thani northwards, with waves of about 2 metres. From Nakhon Si Thammarat southwards, westerly winds of 15–35km/h are expected, with waves of 1–2 metres; waves could exceed 3 metres in thunderstorms in both areas.

Along the Andaman coast on September 26, the TMD forecasts westerly winds of 20–35km/h from Phang Nga northwards, with waves of about 2 metres. From Phuket southwards, southwesterly winds of 15–35km/h are expected, with waves of 1–2 metres; waves could exceed 2 metres in thunderstorms in both areas.