BANGKOK, THAILAND – The Thai weather office warns of ongoing heavy to very heavy rain in many parts of the country. A monsoon depression over the north and northeast, combined with a strong southwest monsoon, is the trigger.
The Meteorology Department advises extreme caution nationwide. Localised but intense rainfall is expected, especially in the north, east, and the west coast of the south.
Heavy rain and flooding risk across the country
The north, northeast, central region, Bangkok, and the southern east coast face strong thunderstorms with heavy rain. Residents have been urged to carefully plan daily travel due to possible flooding.
The Thai Meteorological Department (TMD) warns urgently of flash floods and sudden water runoff from forested areas. The danger is especially high on mountain slopes near waterways and in low-lying basins.
The warning applies particularly to foothills near waterways and low-lying areas.
Monsoon depression and southwest wind drive the storms
A low-pressure trough currently sits over the northern and northeastern provinces of the country. At the same time, a relatively strong southwest monsoon for the season brings extremely moist air masses from the sea.
This combination creates an enormous tendency for showers and thunderstorms. The situation remains tense as long as the large-scale weather pattern does not fundamentally change.
Waves over three metres – boats must stay ashore
At sea, the weather situation also develops into a serious threat. In the upper Andaman Sea, which belongs to Thailand’s west coast, the TMD expects waves of two to three metres. In thunderstorm zones, waves may exceed three metres.
All ships and sailors in the Andaman Sea and the Gulf of Thailand are urged to exercise extreme caution. For small boats in the upper Andaman Sea, the authority recommends staying in port.
Most of the north and east under severe thunderstorms
The forecast for the next 24 hours shows a widespread storm picture. In 70 percent of the northern region, including Mae Hong Son, Chiang Mai, Chiang Rai, and Nan, massive thunderstorms are expected. Isolated very heavy rain is possible in Phetchabun province.
In the east, most of the region is also affected. Provinces like Nakhon Nayok, Rayong, and Chanthaburi must prepare for localised, extremely heavy rain. Sa Kaeo, Chachoengsao, and Chon Buri are also affected.
Central region and greater Bangkok face wet hours
A similar picture emerges in the central region and the capital. For 70 percent of the area, including Bangkok and the surrounding provinces, thunderstorms are forecast. In Nakhon Sawan, Kanchanaburi, and Ayutthaya, rain can be locally heavy.
Temperatures remain tropically warm. In Bangkok, lows are 25 to 27 degrees, highs climb to up to 35 degrees Celsius. The wind blows light to moderate from the southwest.
West coast especially vulnerable – Ranong and Phuket in focus
On the Andaman Sea coast, the west coast of the south, the situation is critical. Phang Nga, Phuket, and Krabi expect heavy rain. For Ranong in the far north of this coast, even very heavy precipitation is forecast in places.
Wave height north of Phang Nga reaches two to three metres, further south around Phuket the sea will be about two metres high. When thunderstorms pass through, significantly higher waves and dangerous seas must be expected everywhere.
Gulf coast also not spared
On the eastern side of the peninsula, towards the Gulf of Thailand, the rain probability is slightly lower at 60 percent. Large parts of Phetchaburi, Prachuap Khiri Khan, Chumphon, and Surat Thani must still expect local heavy rain.
The sea here is comparatively calmer, but waves of one to two metres are also possible on the Gulf. Near thunderstorms, they can quickly swell to over two metres. The TMD also asks for special vigilance here.
Weather office offers continuously updated information
Temperatures in the south range between 22 degrees at night and 34 degrees during the day. On the flood-prone west coast, highs around 33 degrees remain slightly cooler than in the central region.
The Meteorological Department provides current warnings and forecasts around the clock. The authority can be reached on its website at tmd.go.th, by phone at 0-2399-4012-13, or via the national emergency hotline 1182.