BANGKOK, THAILAND – A powerful high-pressure system from China drove intense heat and fueled the risk of strong afternoon thunderstorms across large parts of Thailand on Monday.
High-pressure system pushes heat and storms nationwide
A robust high-pressure system extended from China over the South China Sea to northern Vietnam and directed moist southerly and south-easterly winds into the northeast, central region, Bangkok and the eastern seaboard. This pattern resulted in strong sunshine with temperatures in some areas above 37°C and an elevated risk of afternoon thunderstorms across the northern half of the country. In the south, easterly and south-easterly winds brought isolated showers.
North: hot days, stormy afternoons and cool mountain nights
The northern region, including Chiang Mai and Chiang Rai, was mostly sunny and warm. However, strong afternoon thunderstorms with gusty winds could develop particularly in Mae Hong Son, Tak, Kamphaeng Phet, Phitsanulok and Phetchabun, so outdoor activities were advised mainly for the morning hours. In higher areas such as Doi Inthanon, nighttime conditions could become noticeably cool, making a light jacket advisable.
Northeast: highest temperatures and severe thunderstorm risk
Temperatures in the Isaan region ranked among the highest in the country, reaching up to 38°C. In the provinces of Loei, Nong Bua Lam Phu, Nong Khai, Bueng Kan, Udon Thani and Sakon Nakhon, severe afternoon thunderstorms with gusty winds and lightning were expected. People working outdoors were urged to seek shelter immediately at the first signs of thunder, while mountain areas such as Phu Kradung were forecast to cool to 15–17°C at night.
Central region and Bangkok: oppressive heat and smog
Bangkok and central Thailand experienced oppressive heat combined with haze and smog. Thunderstorms with strong winds were possible in Nakhon Sawan, Lopburi, Saraburi, Kanchanaburi and Ratchaburi, while isolated showers could not be ruled out in the capital. Longer stays outdoors were recommended only in the morning, with Bangkok temperatures around 25–26°C in the early day and 33–37°C at the peak.
Eastern seaboard: dangerous gusts and rising waves
Along the eastern seaboard, including Pattaya and Koh Chang, daytime conditions were intensely hot with maximum temperatures up to 38°C. Isolated thunderstorms and gusty winds were expected in Nakhon Nayok, Prachin Buri, Sa Kaeo, Chachoengsao, Rayong, Chanthaburi and Trat. Nearshore wave heights stayed below one metre under normal conditions but could briefly exceed two metres during thunderstorms, so boat trips required particular caution.
Andaman Sea: mostly friendly, but watch for showers
On the Andaman coast, covering Phuket, Krabi and Khao Lak, the weather was generally fair. Isolated showers were possible, especially in Ranong, Phang Nga, Phuket and Krabi, but were not considered certain. Conditions were favourable for snorkelling and diving, with waves around one metre that could temporarily rise above that level in thunderstorms.
Gulf of Thailand: unsettled seas and thunder risk
In the northern Gulf of Thailand, particularly off Phetchaburi and Prachuap Khiri Khan, thunderstorms with temporarily increased wave heights were possible. In the southern sector, easterly winds of 15–35 km/h made seas noticeably rougher, with waves generally between one and two metres and more than two metres in storms. All vessels were advised to check the latest weather information before departure, and small boats and excursion craft were urged to exercise special caution.
Why the heat-storm pattern is typical for February
The combination of daytime heat and afternoon thunderstorms was attributed to convective storms linked to the high-pressure system. Moist marine air was pushed inland, warmed rapidly near the surface, then rose and cooled at higher altitudes to form thunderclouds. This process was described as typical for the season in Thailand and not unusual in February when the hot summer sets in early.
Health and safety advice from meteorologists
Due to intense solar radiation, residents and visitors were advised to use sun protection with SPF 50 or higher and avoid direct sun between 10 a.m. and 3 p.m. Adequate fluid intake was emphasised, and outdoor activities in storm-prone regions were recommended for the morning.
“Boat operators on the Gulf of Thailand and the Andaman Sea should consult the latest warnings from the meteorological service before every departure,”
said the Thai Meteorological Department, the national weather agency.