Heavy rain forecast for Bangkok and the South as monsoon hits

24-hour outlook

Rainfall is set to intensify in the South, with some areas experiencing very heavy downpours due to the combined influence of north-westerly and north-easterly winds. Thunderstorms and isolated heavy rain will also continue in the Central Region, including Bangkok and surrounding provinces, as well as the East.

The monsoon trough now stretches across the lower North, Central, East and lower Northeast, while a moderate south-westerly monsoon continues to cover the Andaman Sea, the South and the Gulf of Thailand. Residents in these regions are urged to watch out for flash floods and run-off, especially in foothills, near waterways and low-lying areas.

Marine conditions

In the upper Andaman Sea, waves are forecast at 1–2 metres, while the lower Andaman Sea and the Gulf of Thailand will see waves of around one metre. However, in areas with thunderstorms, waves could exceed two metres. Mariners are advised to exercise caution and avoid sailing in stormy zones.

Thailand weather forecast: Sunday (14 September) – Monday (15 September) 

The Meteorological Department has issued a 24-hour forecast from 6am Sunday to 6am Monday, warning of widespread thunderstorms and heavy rain in many regions.

Bangkok and surrounding areas

Thunderstorms in 70% of the area, with isolated heavy rain

Minimum temperature: 25–27°C

Maximum temperature: 33–35°C

Variable winds, 10–15 km/h

Northern region

Thunderstorms in 60% of the area, especially in Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Tak, Phitsanulok, Phichit and Phetchabun

Minimum temperature: 22–25°C

Maximum temperature: 31–35°C

Variable winds, 5–15 km/h

Northeastern region

Thunderstorms in 60% of the area, mainly in Loei, Bueng Kan, Sakon Nakhon, Nakhon Phanom, Chaiyaphum, Khon Kaen, Buri Ram, Surin, Si Sa Ket and Ubon Ratchathani

Minimum temperature: 22–25°C

Maximum temperature: 32–34°C

Easterly winds, 10–15 km/h

Central region

Thunderstorms in 60% of the area, with heavy rain in Lop Buri, Saraburi, Ayutthaya, Kanchanaburi, Ratchaburi, Nakhon Pathom, Samut Sakhon and Samut Songkhram

Minimum temperature: 23–25°C

Maximum temperature: 33–35°C

Variable winds, 10–15 km/h

Eastern region

Thunderstorms in 70% of the area, with heavy rain in Nakhon Nayok, Sa Kaeo, Chachoengsao, Chon Buri, Rayong, Chanthaburi and Trat

Minimum temperature: 23–26°C

Maximum temperature: 30–34°C

Variable winds, 15–30 km/h

Waves about 1 metre; over 2 metres in stormy areas

Southern region (east coast)

Thunderstorms in 70% of the area, with heavy to very heavy rain in Chumphon, Surat Thani, Nakhon Si Thammarat, Phatthalung, Songkhla, Pattani, Yala and Narathiwat

Minimum temperature: 23–25°C

Maximum temperature: 31–34°C

South-westerly winds, 15–30 km/h

Waves about 1 metre; over 2 metres in stormy areas

Southern region (west coast)

Thunderstorms in 70% of the area, with heavy rain in Phangnga, Krabi, Trang and Satun

Minimum temperature: 23–25°C

Maximum temperature: 30–33°C

From Phuket northwards: south-westerly winds, 15–35 km/h; waves 1–2 metres, over 2 metres in stormy areas

From Krabi southwards: south-westerly winds, 15–30 km/h; waves about 1 metre, over 2 metres in stormy areas