Southwest monsoon drives flash flood risk across Thailand
Southwest monsoon strengthens over Thailand, driving heavy to very heavy rainfall and flash flood risk nationwide.
Thailand’s Meteorological Department (TMD) has issued a weather forecast for June 1, warning of heavy to very heavy rainfall across much of Thailand as the southwest monsoon strengthens over the Andaman Sea, the South, and the Gulf of Thailand. A monsoon trough extends across the lower North, upper Central, and lower Northeast regions into a low-pressure cell off the coast of central Vietnam. The combination is driving widespread thundershowers and raising the risk of flash floods and overflows, particularly along foothills, near waterways, and in low-lying areas. Scattered thundershowers and isolated heavy rain are expected in various provinces, including Nakhon Sawan, Uthai Thani, Kanchanaburi, Ratchaburi, Suphan Buri, Nakhon Pathom, and Samut Sakhon. Temperatures will range from 21 to 38°C with variable winds of 10 to 40 km/h. Coastal waves are expected at one to three metres, rising above three metres during thundershowers. The southern west coast faces the most severe conditions of the day, with fairly widespread thundershowers and isolated heavy to very heavy rain forecast for Ranong, Phang Nga, Phuket, Krabi, Trang, and Satun. From Phuket northward, southwesterly winds of 20 to 40 km/h will drive waves in the upper Andaman Sea to two to three metres, exceeding three metres during thundershowers. Small boats in the upper Andaman Sea are advised to remain ashore. The southwest monsoon typically affects Thailand in June, bringing heavy rainfall and flash flood risk to various parts of the country. Phuket buyers should be aware of the heavy rain and flash flood risk due to the southwest monsoon strengthening over the Andaman Sea. The island may experience scattered thundershowers and isolated heavy rain.
What happened
Thailand’s Meteorological Department (TMD) has issued a weather forecast for June 1, warning of heavy to very heavy rainfall across much of Thailand as the southwest monsoon strengthens over the Andaman Sea, the South, and the Gulf of Thailand. A monsoon trough extends across the lower North, upper Central, and lower Northeast regions into a low-pressure cell off the coast of central Vietnam. The combination is driving widespread thundershowers and raising the risk of flash floods and overflows, particularly along foothills, near waterways, and in low-lying areas. Scattered thundershowers and isolated heavy rain are expected in various provinces, including Nakhon Sawan, Uthai Thani, Kanchanaburi, Ratchaburi, Suphan Buri, Nakhon Pathom, and Samut Sakhon. Temperatures will range from 21 to 38°C with variable winds of 10 to 40 km/h. Coastal waves are expected at one to three metres, rising above three metres during thundershowers. The southern west coast faces the most severe conditions of the day, with fairly widespread thundershowers and isolated heavy to very heavy rain forecast for Ranong, Phang Nga, Phuket, Krabi, Trang, and Satun. From Phuket northward, southwesterly winds of 20 to 40 km/h will drive waves in the upper Andaman Sea to two to three metres, exceeding three metres during thundershowers. Small boats in the upper Andaman Sea are advised to remain ashore. The southwest monsoon typically affects Thailand in June, bringing heavy rainfall and flash flood risk to various parts of the country. Phuket buyers should be aware of the heavy rain and flash flood risk due to the southwest monsoon strengthening over the Andaman Sea. The island may experience scattered thundershowers and isolated heavy rain.
Background and context
The development matters for buyers comparing Phuket districts, rental demand, and exit liquidity against Thailand’s broader 2026 market backdrop.
Why it matters for Phuket buyers
For Phuket property buyers, headlines like this shape foreign demand, short-stay rental flow, and how quickly investors move from research to a viewing or offer.
Source: The Thaiger
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