Heavy rain warning issued for Bangkok and other regions

The Meteorological Department of Thailand (TMD) issued a warning for heavy rain across Bangkok today, July 19. Residents are advised to carry umbrellas, and those in hillside areas should be cautious of flash floods.

The TMD’s 24-hour weather forecast indicates a strong monsoon trough crossing the upper northern and upper northeastern regions, combined with a moderately strong southwest monsoon covering the Andaman Sea, the southern, central, and eastern regions, and the Gulf of Thailand.

These conditions are expected to result in heavy rainfall across many parts of the country, with some areas experiencing very heavy rain.

Residents in the northern, northeastern, and eastern regions are advised to be on alert for potential dangers from heavy to very heavy rainfall and accumulated rain, which could lead to sudden flooding and flash floods. This is especially important for those living in hilly areas near waterways and low-lying regions.

In the upper Andaman Sea and the upper Gulf of Thailand, waves are forecasted to be moderately strong, with heights ranging from two to three metres. Areas experiencing thunderstorms could see waves higher than 3 metres.

The lower Andaman Sea is expected to have waves around 2 metres high, with thunderstorms causing waves higher than 2 metres. Seafarers in these areas are advised to navigate with caution and avoid sailing in stormy conditions. Small boats in the upper Andaman Sea and the upper Gulf of Thailand should refrain from leaving the shore at this time.

Regional updates

In the northern region, thunderstorms are expected in 70% of the area, with some places experiencing heavy to very heavy rain. Affected provinces include Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan, Phrae, Uttaradit, Tak, Sukhothai, Phitsanulok, Kamphaeng Phet, Phichit, and Phetchabun. Temperatures will range between 24 to 25 degrees Celsius (°C) at their lowest and 32 to 34°C at their highest. Winds will vary between speeds of 10 to 20 kilometres per hour (km/h).

In the northeastern region, thunderstorms are predicted in 80% of the area, with some locations seeing heavy to very heavy rain. Provinces affected include Loei, Chaiyaphum, Nong Khai, Bueng Kan, Nong Bua Lamphu, Udon Thani, Sakon Nakhon, Nakhon Phanom, Khon Kaen, Kalasin, Mukdahan, Maha Sarakham, Roi Et, Yasothon, Amnat Charoen, Nakhon Ratchasima, Buriram, Surin, Si Sa Ket, and Ubon Ratchathani. Temperatures will range from 23 to 24°C at their lowest to 29 to 32°C at their highest. Winds will be variable at speeds of 10 to 20 km/h.

In the central region, thunderstorms are expected in 60% of the area, with some places experiencing heavy rain. Affected provinces include Nakhon Sawan, Lopburi, Saraburi, Phra Nakhon Si Ayutthaya, Kanchanaburi, and Ratchaburi. Temperatures will range from 24 to 25°C at their lowest to 32 to 33°C at their highest. Southwest winds will blow at speeds of 10 to 25 km/h.

In the eastern region, thunderstorms are predicted in 80% of the area, with some locations experiencing heavy to very heavy rain. Affected provinces include Nakhon Nayok, Prachinburi, Chachoengsao, Chon Buri, Rayong, Chanthaburi, and Trat. Temperatures will range from 24 to 27°C at their lowest to 28 to 33°C at their highest. Southwest winds will blow at speeds of 20 to 40 km/h. The sea will have waves 2 to 3 metres high, with waves higher than 3 metres in thunderstorm areas.

In the southern region (east coast), thunderstorms are expected in 40% of the area, with some places experiencing heavy rain. Affected provinces include Phetchaburi, Prachuap Khiri Khan, and Chumphon. Temperatures will range from 23 to 25°C at their lowest to 32 to 36°C at their highest.

From Surat Thani upwards, southwest winds will blow at speeds of 20 to 35 km/h. The sea will have waves around 2 metres high, with waves higher than 2 metres in thunderstorm areas. From Nakhon Si Thammarat downwards, southwest winds will blow at speeds of 15 to 35 km/h. The sea will have waves 1 to 2 metres high, with waves higher than 2 metres in thunderstorm areas.

Heavy rain

In the southern region (west coast), thunderstorms are expected in 40% of the area, with some places experiencing heavy rain. Affected provinces include Ranong, Phang Nga, and Phuket. Temperatures will range from 24 to 25°C at their lowest to 31 to 34°C at their highest.

From Phuket upwards, southwest winds will blow at speeds of 20 to 40 km/h. The sea will have waves 2 to 3 metres high, with waves higher than three metres in thunderstorm areas. From Krabi downwards, southwest winds will blow at speeds of 20 to 35 km/h. The sea will have waves around 2 metres high, with waves higher than 2 metres in thunderstorm areas.

In Bangkok and surrounding areas, thunderstorms are predicted in 70% of the area, with some locations experiencing heavy rain. Temperatures will range from 26 to 27°C at their lowest to 33 to 35°C at their highest. Southwest winds will blow at speeds of 10 to 25 km/h.