Press "Enter" to skip to content

TMD Warns: Heavy Monsoon Storms and Flood Risk in 37 Provinces (Aug 29–30, 2025)

Thailand is gearing up for a dramatic weather performance as the Meteorological Department (TMD) warns of widespread thunderstorms and torrential downpours sweeping across 37 provinces today. From 6:00 AM on August 29 until 6:00 AM on August 30, a moody monsoon trough draped over the North and a steady southwesterly monsoon pushing across the Andaman Sea, Thailand, and the Gulf will make sure umbrellas and rain boots are back in the spotlight.

Who’s in the line of fire?

The TMD’s alert is particularly stern for northern provinces famous for stunning mountains and narrow roads—Mae Hong Son, Chiang Mai, Chiang Rai, and Nan. Residents there should brace for flash floods and forest runoff that can turn familiar paths into fast-moving waterways in no time. In the North broadly, about 60% of the region is expected to see thunderstorms, with heavy rain targeted at Phayao, Nan and the four high-risk provinces listed above. Temperatures will feel cool to mild, roughly 22°C to 32°C, with southwesterly winds blowing at 10–20 km/h.

The Northeast is getting the same dramatic treatment — thunderstorms are forecast for some 60% of the region. Keep an eye on Chaiyaphum, Khon Kaen, Kalasin, Mukdahan, Mahasarakham, Roi Et, Yasothon, Amnat Charoen, Surin, Sisaket and Ubon Ratchathani, which are all on high alert. Expect warm, humid air with temperatures between 23°C and 33°C and winds of 10–20 km/h gusting around sudden squalls.

Central, East and Bangkok — don’t get too comfortable

Central Thailand will see storms in about 40% of the region. Watch for heavy clouds and sudden downpours near Kanchanaburi, Ratchaburi, Lopburi and Saraburi. Temperatures could climb as high as 35°C before the rain breaks, creating that familiar hot-then-dump pattern monsoon season fans love to hate.

The Eastern provinces — including Rayong, Chanthaburi and Trat — are also expected to be wet, with rough sea conditions possible. The TMD warns that waves could top 2 metres in stormy zones, making coastal areas and small boating activities risky until the seas calm.

And yes, Bangkok and surrounding areas are not immune: there’s a 40% chance of thunderstorms across the capital, where temperatures will hover between 26°C and 35°C. Expect sudden, heavy showers that can cause flash flooding in low-lying districts and send traffic into the usual slow-motion drama.

Southern coasts — double trouble

The southern provinces will be soaking wet on both coasts. On the Gulf coast, storms may affect roughly 40% of the area — Chumphon, Surat Thani, Nakhon Si Thammarat and Songkhla are likely to see squalls. The Andaman coast is set for heavy rain in Ranong, Phang Nga, Phuket, Krabi, Trang and Satun, with waves reaching up to 2 metres. Boaters, fishers and beach-goers should pay attention: rough seas and sudden storms can appear with little warning.

Keep an eye on the South China Sea

The TMD is closely monitoring a strong low-pressure system in the upper South China Sea that could intensify into a tropical cyclone. If that happens, expect a ramp-up in wind strength and rain volume in affected areas. Sailors and anyone planning sea travel are urged to steer clear of stormy zones and navigate with extreme caution — or better yet, stay docked until authorities give the all-clear.

Practical tips — what you should do now

  • Stay informed. Check official TMD updates and local advisories regularly; conditions can change fast.
  • Secure property. Bring loose outdoor items inside and check drainage around your home to reduce flood risk.
  • Avoid floodwaters. Never drive through standing water — even shallow water can trap or sweep vehicles away.
  • Boaters and fishers: postpone trips. High waves and squalls make small craft especially vulnerable.
  • Prepare an emergency kit. Keep essentials—water, flashlight, phone chargers, medicines—handy in case power or transport is disrupted.

Whether you’re watching the skyline darken in Chiang Mai or bracing for a sudden splash in Bangkok, this monsoon episode is a reminder that Thailand’s weather can turn from sultry to stormy in a heartbeat. Follow the TMD, take sensible precautions, and don’t let a rogue thunderstorm ruin your day — unless you secretly like dramatic weather, in which case, enjoy the show (from a safe, dry place).

Photo credits and social snippets circulating online — including posts from The Thaiger and various iStock contributors — highlight the soggy scenes expected across the country. Stay safe, stay updated, and keep that umbrella handy.

34 Comments

  1. ThaiTimes August 29, 2025

    We posted the TMD alert to keep readers informed; please follow official updates and local advisories. If you live in the highlighted provinces, secure loose items and check drains now. We will update if the low-pressure system in the South China Sea intensifies.

  2. Joe August 29, 2025

    Why is the government always late to fix drainage? Every year same story, same flooded roads. When will someone actually do something about it?

    • Maya Singh August 29, 2025

      It’s not just the government — urban planning and budget priorities matter too. But yes, repeated flooding suggests systemic failure and lack of long-term investment.

      • Somchai August 29, 2025

        Budget priorities? More like corruption and ignoring engineers who warned years ago. We need accountability, not press releases.

  3. Nong August 29, 2025

    Rain again? Yay, no school! But please don’t let the river come to our house.

    • InspectorBan August 29, 2025

      Kids love it until their homes flood. We in local disaster teams are stretched thin, and warnings help but resources are limited.

      • ThaiTimes August 29, 2025

        Thanks for your work, InspectorBan — can you share tips on the best local channels residents should monitor for rapid updates?

  4. Dr. Arun Patel August 29, 2025

    This pattern fits climate model projections: stronger monsoon variability and more intense rainfall events. Long-term adaptation — not just emergency response — must be prioritized.

  5. Suriya August 29, 2025

    You scientists always say ‘adaptation’ but what does that even mean for a farmer with no savings? We need concrete subsidies and flood-resistant crops.

    • grower134 August 29, 2025

      As a small farmer I agree; seeds and support matter. But many aid programs are bureaucratic and slow when floods hit.

    • YoungVoter August 29, 2025

      This is political too — vote for candidates who actually finance rural resilience. Empty promises won’t stop crop losses.

  6. Larry D August 29, 2025

    Tourism will take a hit again and the economy suffers. Why don’t tour operators refund faster and stop promising sunny beach days?

    • Ploy August 29, 2025

      Many small operators are bleeding cash too; blanket refunds are hard. But communication and flexible vouchers could help both sides.

    • TourGuide August 29, 2025

      I guide in Krabi and felt a 50% drop last season after storms. Safety comes first, but the industry needs clearer contingency plans.

  7. Kai August 29, 2025

    Bangkok floods again and the traffic becomes a parking lot. Are elevated roads and better pumps too expensive for the city?

    • BangkokDriver August 29, 2025

      I drive through Rama IV daily; just one heavy shower and streets are chaos. Simple fixes like clearing drains would help but no one enforces it.

      • Mai August 29, 2025

        Clearing drains helps but you also need green spaces to absorb rain. Concrete everywhere makes the problem worse.

  8. Fisherman August 29, 2025

    We never go out if waves over 1.5m, but the bulletin says 2m in some areas. Fishing incomes will drop and safety is at risk.

    • Captain_Lee August 29, 2025

      As a skipper I advise all small craft to stay ashore until seas calm. A small storm can flip a boat in minutes.

    • SeaLover August 29, 2025

      I love the ocean but storms are no joke. Authorities should close small harbors proactively rather than wait for rescues.

  9. Professor Chen August 29, 2025

    We should link this to global trends: warmer seas increase moisture and storm energy. ASEAN countries must coordinate regional early-warning systems.

  10. Anon6 August 29, 2025

    Coordination sounds good on paper, but politics and funding kill most regional initiatives. Who will actually pay for shared satellites and sensors?

    • Suda August 29, 2025

      International development banks and climate funds exist for a reason. But domestic governance must be ready to absorb and use that money well.

  11. Editor August 29, 2025

    TMD warnings are helpful, but sometimes forecasts are too vague for action. Can agencies provide more localized, hourly risk indicators for roads and schools?

    • WeatherNerd August 29, 2025

      Localized nowcasting with radars is possible; the issue is investment and data sharing. Some private weather firms already offer hyperlocal alerts for a fee.

    • ThaiTimes August 29, 2025

      We can push for more detailed local maps in our next piece; readers, which districts should we prioritize for hyperlocal coverage?

    • Chai August 29, 2025

      Start with Chiang Mai’s mountain routes and Bangkok lowlands; those areas suffer the most sudden impacts and need targeted alerts.

  12. Grandma Noi August 29, 2025

    I will bring my grandchildren inside and say prayers. Stay safe, everyone and keep the torches ready if power goes out.

  13. Engineer Tom August 29, 2025

    Technical point: pump capacity and retention basins reduce peak runoff, but retrofitting cities is complex and expensive. Still, designs exist that pay off over decades.

  14. Citizen42 August 29, 2025

    Long-term payoffs are great, but where is the political will? Politicians prefer flashy projects, not boring infrastructure maintenance.

  15. PhuketFan August 29, 2025

    I booked a trip to Phuket next week — should I cancel? Beaches will be wet but maybe still walkable between storms.

    • Anna August 29, 2025

      Check airline and hotel policies; many allow free changes under official warnings. Your safety is more important than a beach selfie.

      • Samantha August 29, 2025

        As someone who had a cancelled trip last year, get travel insurance that covers storms. It saved me from losing a lot of money.

  16. Mek August 29, 2025

    I think people overreact online but don’t take simple precautions in real life. Bring sandbags if you live near streams and learn escape routes.

Leave a Reply to ThaiTimes Cancel reply

Your email address will not be published. Required fields are marked *

More from ThailandMore posts in Thailand »