Weather alert covers Bangkok flood risks and heavy rain in the South
Upper Thailand faces thundershowers and hail, with heavier rain in the South and waves exceeding two metres where thundershowers occur at sea.
- A weather alert is in effect for Thailand from November 5-9 due to a cold air mass from China causing sudden weather changes.
- Bangkok and surrounding provinces face a high risk of flooding from November 5-7 as a result of thundershowers and heavy rain.
- Southern Thailand is expected to receive heavy to very heavy rain from November 7-9, creating a risk of flash floods and forest run-off.
- Mariners are also warned of strong winds and waves exceeding 2 meters in the Gulf of Thailand and Andaman Sea during thundershowers.
The Thai Meteorological Department and the Bangkok Metropolitan Administration (BMA) have warned people across Thailand, including Bangkok and surrounding provinces, to prepare for sudden weather changes from Thursday (November 5, 2026) to November 9.
Residents should plan their travel and daily activities carefully.
New cold air mass drives unsettled weather
A fresh high-pressure system, or cold air mass, from China has spread over upper Thailand and the South China Sea, significantly strengthening easterly winds across Thailand and the Gulf of Thailand.
Its interaction with moisture over Thailand is driving the unsettled conditions.
Affected areas and periods to monitor
The department has outlined when different regions will be affected to help residents monitor conditions and prepare.
1. Upper Thailand, Bangkok and surrounding provinces — November 5–7
Upper Thailand will experience thundershowers, gusty winds, hail and isolated heavy rain during this period.
- The cold air mass and thundershowers will affect the Northeast (Isan) first.
- The North, Central region and East will be affected next, along with Bangkok and surrounding provinces, where there is a high risk of floodwater collecting at several vulnerable locations before it can drain away.
2. Heavy to very heavy rain in the South — November 7–9
As the cold air mass continues to spread, easterly winds across the Gulf of Thailand will strengthen considerably, bringing a marked increase in rainfall to the South.
- Heavy rain is expected in many areas, with isolated very heavy rain.
- Accumulated rainfall could cause flash floods and forest run-off, particularly on foothill slopes near waterways and in low-lying areas.
Strong wind and wave warning for the Gulf of Thailand and Andaman Sea
Female traders, mariners and tourists should also take extra care, paying attention to boat conditions and winds and waves at sea.
- Waves in the Andaman Sea and the Gulf of Thailand will exceed 2 metres in areas with thundershowers.
- Mariners should navigate with caution and avoid sailing through thundershowers to protect lives and property.
Precautions against unsettled weather
People in at-risk areas should follow these precautions closely to reduce the impact of the weather and the risk of harm:
- Beware of gusty winds and lightning. Avoid open areas, and do not approach or shelter beneath large trees, unstable structures or large advertising boards.
- Check that homes are secure. Inspect roofs, trees and structures around the home to ensure they are sturdy enough to withstand gusty winds.
- Allow extra travel time in Bangkok and surrounding provinces, as flooding on main and secondary roads could cause severe traffic congestion.
- People in the South should remain alert to flooding. Those in at-risk areas should move belongings to higher ground, prepare sandbags and monitor water conditions closely.
Reporting flooding and requesting assistance in Bangkok
Bangkok residents can report standing floodwater or blocked drains, or request emergency assistance, through the following channels:
- BMA hotline: 1555, available 24 hours a day.
- LINE: @Traffyfondue. Reports can be submitted immediately with a location and photographs.
- Facebook: ศูนย์ป้องกันน้ำท่วม กทม.
- Control centre for flood prevention systems on main roads: 0 2248 5115.
Official weather information
Residents should remain calm and continue following warnings from government authorities and the Thai Meteorological Department for accurate, timely information.
- Thai Meteorological Department website.
- Thai Meteorological Department hotline: 1182 or 0-2399-4012-13, available 24 hours a day.
