Severe summer storms hit northern Thailand – authorities warn of hail and gale force winds

The Thailand Meteorological Department (TMD) has issued a warning for severe summer storms expected to affect northern, northeastern and central Thailand until May 1, 2025. According to the TMD, the storm will bring thunderstorms, strong winds, hail and isolated heavy rain, as well as an increased risk of lightning strikes.

Which areas are affected?

According to TMD's weather warning No.12 (105/2025), the following provinces will be affected:

Apr 29, 2025:

• Northern Thailand: Mae Hong Son, Chiang Mai, Chiang Rai, Lamphun, Lampang, Phayao, Nan, Phrae, Uttaradit, Sukhothai, Kamphaeng Phet, Tak, Phitsanulok, Phichit and Phetchabun.
• Central Thailand: Nakhon Sawan, Uthai Thani, Chai Nat, Lop Buri and Kanchanaburi.

Apr 30, 2025:

• Northern Thailand: Chiang Mai, Lamphun, Lampang, Nan, Phrae, Uttaradit, Sukhothai, Kamphaeng Phet, Tak, Phitsanulok, Phichit and Phetchabun.
• Northeast Thailand: Loei, Nong Khai, Bueng Kan, Nong Bua Lam Phu, Udon Thani, Chaiyaphum, Khon Kaen and Nakhon Ratchasima.
• Central Thailand: Nakhon Sawan, Uthai Thani, Chai Nat, Kanchanaburi, Lop Buri and Saraburi.

1 May 2025:

• Northern Thailand: Chiang Mai, Lamphun, Lampang, Nan, Phrae, Uttaradit, Sukhothai, Kamphaeng Phet, Tak, Phitsanulok, Phichit and Phetchabun.
• Northeast Thailand: Loei, Nong Khai, Bueng Kan, Nong Bua Lam Phu, Udon Thani, Sakon Nakhon, Nakhon Phanom, Kalasin, Mukdahan, Khon Kaen, Maha Sarakham, Roi Et, Yasothon, Chaiyaphum and Nakhon Ratchasima.
• Central Thailand: Nakhon Sawan, Uthai Thani, Chai Nat and Lop Buri.

Source: Thai Meteorological Department – ​​Summer Thunderstorm Advisory No.12 (105/2025)

Why do storms occur?

TMD explains that a high pressure area from China extending over Vietnam and the South China Sea is helping to create a convergence of southeasterly and southwesterly winds over Thailand. At the same time, a westerly trough from Myanmar is moving over northern and northeastern Thailand, triggering summer storms in the regions.

The warm weather combined with wind changes is creating unstable atmospheric conditions, leading to severe thunderstorms and hailstorms.

Authorities' appeals to residents

TMD and the Department of Disaster Prevention and Mitigation (DDPM) urge residents in affected areas to:

• Avoid being outdoors during thunderstorms.
• Do not park vehicles under trees or advertising signs.
• Reinforce buildings and loose objects that could be damaged by strong winds.
• Protect crops and livestock from damage from hail and strong winds.
• Follow local government updates and emergency announcements.

The transport sector has also warned of difficulties on roads and in air traffic during the storm period.

When is the weather expected to improve?

The severe summer storms are expected to gradually subside after May 1, 2025. However, TMD emphasizes that further weather changes may occur due to movements of air masses from Myanmar and China. The next official weather update from TMD will be published on April 30, 2025.

Summer season in Thailand

Thailand has three main seasons: rainy season, dry season and summer. The summer season, which runs from mid-February to mid-May, is characterized by very hot weather in much of the country.

• Temperatures: During April and May, daytime temperatures often reach over 30 degrees Celsius, especially in inland areas such as Chiang Mai and Bangkok.
• Weather patterns: The heat is often combined with increasing humidity, which creates instability in the atmosphere and can trigger severe summer storms.
• Regional differences: In southern Thailand, the climate is milder year-round thanks to the influence of the sea, while northern and northeastern Thailand can experience very high daytime temperatures.
• Rain: In April and May, rainfall begins to increase, especially in the southern and central regions. For example, Phuket receives an average of 125 mm of rain in April and 295 mm in May.

According to the Thailand Meteorological Department (TMD), April and May are also the time when the weather can quickly shift from warm and sunny to severe storms due to the interaction between local heat effects and incoming monsoon winds from the sea.

Text: The editorial staff

Image license: DerTobiSturmjagd, Pixabay, original image