Heavy rainfall and flash flood warnings issued for 50 provinces

Heavy rainfall is expected across 50 provinces today, with 70% of these areas, including Bangkok, set to experience significant downpours. The Thai Meteorological Department (TMD) warns of potential flash floods and forest runoffs due to the weather conditions.

The TMD forecasted the weather for the next 24 hours, noting that a monsoon trough is passing over the upper northern and northeastern regions of Thailand and Laos.

This, combined with a moderate southwest monsoon covering the Andaman Sea, Thailand, and the Gulf of Thailand, will lead to heavy rainfall in some northern areas. The eastern parts of the northeast and the eastern region will see extremely heavy rainfall in certain areas.

Residents in these regions are advised to be cautious of the heavy to very heavy rainfall and the accumulated precipitation, which could result in flash floods and forest runoffs, especially in foothill areas near waterways and low-lying regions.

The Andaman Sea and the upper Gulf of Thailand are expected to experience moderate winds and waves. The upper Andaman Sea will have waves around 2 metres high, while the lower Andaman Sea and the upper Gulf of Thailand will have waves between 1 and 2 metres high.

In stormy areas, waves could exceed 2 metres. Mariners in these areas are advised to navigate with caution and avoid sailing in stormy regions.

Meanwhile, a depression in the upper South China Sea, approximately 300 kilometres southeast of Hainan Island, China, is expected to intensify into a tropical storm. This storm is projected to pass over Hainan Island and make landfall in southern China between July 21 and 23. Though it will not directly affect Thailand’s weather, travellers to the affected areas should check the weather conditions before setting out.

Heavy rainfall

The weather forecast for Thailand from 6am today to 6am tomorrow is as follows:

In the northern region, thunderstorms are expected in 70% of the area, with heavy rainfall in some parts, including Mae Hong Son, Chiang Mai, Chiang Rai, Phayao, Nan, Uttaradit, Tak, Phitsanulok, and Phetchabun. Temperatures will range from 24 to 26°C at the lowest to 31 to 34°C at the highest, with southwest winds blowing at 10 to 20 kilometres per hour.

The northeastern region will also see thunderstorms in 70% of the area, with very heavy rainfall in certain parts, including Loei, Nong Khai, Bueng Kan, Udon Thani, Sakon Nakhon, Nakhon Phanom, Khon Kaen, Kalasin, Mukdahan, Maha Sarakham, Roi Et, Yasothon, Amnat Charoen, Surin, Sisaket, and Ubon Ratchathani. Temperatures will range from 24 to 26°C at the lowest to 30 to 34°C at the highest, with southwest winds at 10 to 20 kilometres per hour.

In the central region, thunderstorms are likely in 60% of the area, primarily affecting Nakhon Sawan, Uthai Thani, Lopburi, Saraburi, Phra Nakhon Si Ayutthaya, Kanchanaburi, Ratchaburi, Nakhon Pathom, and Samut Sakhon. Temperatures will range from 24 to 27°C at the lowest to 33 to 35°C at the highest, with southwest winds at 10 to 20 kilometres per hour.

The eastern region will experience thunderstorms in 70% of the area, with very heavy rainfall in some parts, including Nakhon Nayok, Prachinburi, Chachoengsao, Rayong, Chanthaburi, and Trat. Temperatures will range from 24 to 28°C at the lowest to 28 to 32°C at the highest, with southwest winds at 15 to 35 kilometres per hour. The sea will have waves between 1 and 2 metres high, with waves exceeding 2 metres in stormy areas.

In the southern (east coast) region, thunderstorms are expected in 40% of the area, mainly affecting Phetchaburi, Prachuap Khiri Khan, Chumphon, Surat Thani, and Nakhon Si Thammarat. Temperatures will range from 24 to 26°C at the lowest to 32 to 36°C at the highest.

From Surat Thani upwards, southwest winds will blow at 15 to 35 kilometres per hour, with waves between 1 and 2 metres high, exceeding 2 metres in stormy areas. From Nakhon Si Thammarat downwards, southwest winds will blow at 15 to 30 kilometres per hour, with waves around 1 metre high, exceeding 1 metre in stormy areas.

The southern (west coast) region will see thunderstorms in 40% of the area, mainly affecting Ranong, Phang Nga, Phuket, and Krabi. Temperatures will range from 24 to 27°C at the lowest to 32 to 35°C at the highest.

From Ranong upwards, southwest winds will blow at 20 to 35 kilometres per hour, with waves around 2 metres high, exceeding 2 metres in stormy areas. From Phang Nga downwards, southwest winds will blow at 15 to 35 kilometres per hour, with waves between 1 and 2 metres high, exceeding 2 metres in stormy areas.

In Bangkok and surrounding areas, thunderstorms are expected in 60% of the area. Temperatures will range from 26 to 28°C at the lowest to 32 to 35°C at the highest, with southwest winds at 10 to 20 kilometres per hour.