September falls in the heart of the monsoon season in Thailand, where cities and towns are accustomed to the afternoon rains and thunderstorms that frequently roll through. But throughout late September and early October 2026, persistent heavy rains punctuated by intense downpours left low-lying areas across the country in Southeast Asia under sustained flooding.
Prachin Buri province was among the areas where flooding was widespread. The right image above shows land along the Bang Pakong River and nearby agricultural areas and aquaculture facilities inundated on October 2, 2026. The left image shows the same area at the same time of year in 2025. Acquired with NASA-USGS Landsat satellites, the images are false-color to better distinguish water from vegetation, developed land, and other surfaces. The bright red shapes are floating solar arrays.
Some of the flooding likely stemmed from a low-pressure system that stalled over the area for several days in late September. Stoked by moisture and energy from the warm Gulf of Thailand nearby, the system delivered especially intense rains to the region. About 100 kilometers (60 miles) to the west, Bangkok received nearly 300 millimeters (11.8 inches) of rain over a 48-hour period, according to news reports, close to the average monthly rainfall total for September of 344 millimeters (13.5 inches).
Since mid-September, flooding has occurred in 50 provinces across the country, affecting over 4 million people and causing dozens of deaths, according to the International Federation of Red Cross and Red Crescent Societies. Government agencies estimate about 270,000 hectares (670,000 acres) of farmland, including rice fields and fruit orchards, have been damaged.
NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey. Story by Lindsey Doermann.
References & Resources
- ABC News (2026, September 28) Residents brave floodwater for supplies after Bangkok inundated. Accessed October 7, 2026.
- The Conversation (2026, October 5) As the planet warms, cities like Bangkok could be increasingly inundated by deadly floods. Accessed October 7, 2026.
- The Nation (2026, October 7) Thailand floods hit 1.7m rai including over 26,000 rai of orchards. Accessed October 7, 2026.
- ReliefWeb (2026, October 6) THA: Flood - 09-2026 - Heavy rainfall caused flooding #3. Accessed October 7, 2026.
