BANGKOK: The Thai Meteorological Department (TMD) has warned of isolated heavy to very heavy rain across upper Thailand from Friday to Monday (Sept 4-7, 2026), raising the risk of flash floods and run-off.
The warning appeared in Advisory No.1 (181/2026), issued at 5am on Wednesday (Sept 2). The North and Northeast are expected to face the most intense rainfall.
The department attributed the conditions to a monsoon trough extending across the North and upper Northeast, combined with a moderate south-west monsoon prevailing over the Andaman Sea, Thailand and the Gulf of Thailand.
The advisory did not identify individual provinces, specifying only the North and Northeast as the areas of greatest concern.
Upper Thailand faces rain and flood risk through Sept 7
TMD warned that heavy and accumulated rainfall could cause flash floods, rapid run-off and short-term inundation.
Residents and travellers were advised to:
>Monitor conditions in foothill areas near waterways and in low-lying locations
>Avoid routes repeatedly affected by flooding
>Exercise particular caution in low-lying areas where water may accumulate quickly
>Plan daily activities and journeys carefully during the warning period
Tropical Storm Saudel, located over the upper South China Sea, is forecast to move close to Taiwan between Saturday and Monday (Sept 5-7).
People planning to travel to Taiwan or nearby areas should check weather conditions before departure.
Weather information is available around the clock through the TMD website and its telephone numbers, 0-2399-4012-13 and 1182.
The department is scheduled to issue its next advisory at 5pm on Wednesday. - The Nation/ANN
