TMD issues Thailand warning for heavy rain, hail and flash floods
The Thai Meteorological Department (TMD) has warned of heavy to very heavy rain, gusty winds and hail in parts of Thailand through October 7, with flash floods and forest run-off possible in vulnerable areas. In Warning…
Source: The Nation Thailand · October 5, 2026 at 4:02 PM · AI-assisted report
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THAILAND, 5 OCTOBER 2026 —
The Thai Meteorological Department (TMD) issued Warning No. 9 at 5 p.m. on Monday, 5 October, alerting that heavy to very heavy rain, gusty winds and hail would affect large parts of Thailand through 7 October. The warning warned that flash floods and forest run‑off could occur in vulnerable areas.
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The TMD said the unstable weather would cover upper Thailand from 5–7 October, bringing thunderstorms, gusty winds, hail and locally heavy to very heavy rain. The North, the Central region—including Bangkok and its vicinity—the East and the upper South were expected to experience the main effects on 5–6 October, while rainfall in the Northeast was forecast to ease.
By 7 October the areas most affected were expected to shift toward the western parts of the North and Central regions. The department attributed the conditions to a high‑pressure system or cool air mass from China extending over the North and upper Northeast at the end of the rainy season, with the southwest monsoon continuing over the Andaman Sea, the South and the Gulf of Thailand.
The TMD urged people to watch for thunderstorms, gusty winds and heavy or accumulated rainfall that could trigger flash floods and forest run‑off. Those living on foothills, near waterways and in low‑lying areas were advised to be particularly cautious, as flooding could develop where drainage is limited. The public was also warned to avoid open areas, large trees and insecure billboards during thunderstorms and strong winds.
Winds and waves in the Andaman Sea and Gulf of Thailand were expected to strengthen, with waves exceeding two metres in thunderstorm areas. Mariners were told to check weather and sea conditions before travelling, navigate with caution and avoid areas affected by thunderstorms.
The TMD also forecast an increase in rainfall from 9–13 October across the East, the Central region—including Bangkok and its vicinity—and the South, with heavy to very heavy rain possible in some areas.
The warning was reported by The Star and The Nation. The Star noted that the severe weather creates a high risk of flash floods and sudden runoff, particularly on foothill slopes and in low‑lying areas. It added that the high‑pressure system or cold air mass from China was initially triggering thundershowers, and that the southwest monsoon continued to prevail over the Andaman Sea, the South and the Gulf of Thailand.
The Nation reiterated that heavy and accumulated rainfall could cause flash floods and sudden runoff from higher ground, especially on foothill slopes near waterways and in low‑lying areas, and that standing floodwater was also possible in low‑lying areas. It advised people to beware of gusty winds and to avoid open spaces or areas beneath large trees or unsecured billboards.
It also warned that winds and waves in the Andaman Sea and Gulf of Thailand were expected to strengthen, with waves exceeding two metres in thundershowers, and that mariners should check their routes, navigate cautiously and avoid sailing through thundershowers. Rain was expected to continue in the East and South during 8–13 October, with isolated heavy to very heavy rainfall, and people were advised to follow weather forecasts closely.
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