The Thai Meteorological Department has issued a severe weather warning for 69 provinces, forecasting heavy rain, flash floods, and rough seas between 19 and 21 May.
This unsettled weather will affect major expatriate hubs, including Bangkok, Chiang Mai, and Phuket. A strong monsoon is driving these conditions. British nationals living in or travelling to these regions should prepare for potential infrastructure disruption.
Inland Flooding Risks
Rainfall will increase steadily across the country over the three-day period. Western regions face the highest risk of severe downpours. The department advises residents in low-lying areas, near waterways, or on hillsides to monitor for flash floods and forest run-off.
Expatriates in Bangkok and surrounding provinces should anticipate localised street flooding and heavy traffic delays. Property owners in vulnerable zones ought to secure outdoor items. Water levels can rise rapidly.
Coastal and Marine Disruptions
Marine conditions will deteriorate significantly. In the upper Andaman Sea, covering areas from Phuket northwards, waves are expected to reach up to three metres. During thunderstorms, these swells will rise even higher.
The lower Andaman Sea and the upper Gulf of Thailand will experience two-metre waves, creating hazardous conditions for island transfers. All vessels must proceed cautiously. Small boats in the upper Andaman should remain ashore. Those planning ferry travel to southern islands should verify schedules with operators before departing.
Practical Advice for Residents
Provincial weather impacts will shift daily. On 20 May, the heaviest rain will concentrate on northern and eastern provinces, moving towards central areas by 21 May. British residents should track local forecasts.
Official updates are available directly through the Thai Meteorological Department website. Alternatively, individuals can access information via the 24-hour telephone hotlines on 0-2399-4012-13 and 1182.
