GISTDA warns that saturated soil in central and eastern regions, combined with heavy rain accumulation, risks flash floods and surface runoff, focusing on flood-prone areas in Bangkok and the Chao Phraya basin that require vigilance.
Thailand is currently facing “heavy to very heavy rainfall” across many areas nationwide from 23 to 27 September 2026. Today (25 Sep), the Geo-Informatics and Space Technology Development Agency (Public Organization), or GISTDA, is using satellite technology and geospatial data to monitor and track the water situation across Thailand in real time via the “Check Water” application. Data as of 08:38 AM reveals affected areas and zones at risk from continuous heavy rainfall.
Regarding flooding in the central and lower northern regions, satellite image analysis shows a worrying expansion of high-risk (red) zones covering several provinces, including Nakhon Sawan, Phichit, Phetchabun, Lopburi, Saraburi, Suphanburi, extending down to Pathum Thani, Nonthaburi, and parts of Bangkok. There are also danger alerts and waterlogged road points scattered along key routes.
In the northeastern region, lower areas along river basins are submerged. Satellite images show dense high-risk (red) clusters in the lower Isan region, covering Surin, Sisaket, Buriram, and Roi Et provinces. Water has flooded low-lying riverside and agricultural lands extensively, impacting residents’ livelihoods.
Nationally, the overall picture shows warning points (yellow symbols) and danger points (red symbols) spread across the north, northeast, central, and southern regions.
Processing satellite data is crucial for water management agencies, the Department of Disaster Prevention and Mitigation (DDPM), and local authorities to assess water flow directions, plan drainage into the sea, and provide timely, targeted assistance to affected people.
GISTDA emphasizes that residents in high-risk red zones and low-lying areas near waterways should closely monitor weather and water level updates, exercise caution when traveling through waterlogged roads, prepare to elevate belongings, and relocate livestock and vehicles to safe areas.
Thairath Online’s special news team spoke with Dr. Suraswadi Phumiphanich, GISTDA spokesperson, who revealed that GISTDA’s satellite image analysis has detected widespread flooding recently. Meteorological forecasts indicate a strong low-pressure area moving into eastern and central regions, including Bangkok and its vicinity, causing continuous heavy rain through 27 September 2026.
The August to October period annually is normally when the monsoon trough passes over Thailand, though intensity varies with climate changes. Looking at river basins, the Chao Phraya basin is currently at high risk of overflow. GISTDA’s soil moisture data shows that soils in central Thailand are quite saturated and humid. High moisture is also found in eastern river basins, especially in Chachoengsao, Prachinburi, and parts of Chanthaburi and Trat provinces.
“This data indicates that when soil moisture is very high, additional rain can cause surface runoff, requiring close monitoring. In highland areas, flash flood risks must be watched.”
GISTDA has developed the “Check Water” application using hourly rainfall forecast data from various CCTV cameras. Evaluations show that the central basin area is among the highest priority for monitoring due to high soil moisture and forecasts of continued rain over the next 2–3 days, increasing water volume, along with greater releases from the Chao Phraya Dam than before.
For Bangkok, forecast data as of today (25 Sep) identifies risk areas along the Chao Phraya River and several districts such as Bang Sue, Chatuchak, Phaya Thai, and Din Daeng. However, rainfall amounts need ongoing monitoring, as forecasts may change depending on whether rain increases or decreases.
If there is additional high tide, drainage will slow, requiring increased vigilance in riverside communities. Currently, several riverside areas in Phra Nakhon Si Ayutthaya province, such as Bang Ban and Sena districts, are already flooded due to water released from the Chao Phraya Dam.
Asked when the flooding situation might ease, the GISTDA spokesperson said the Chao Phraya Dam continues to release water at rates exceeding 1,000 cubic meters per second, so riverside communities remain affected and need assistance. The dam’s release rates over the next 2–3 days will determine whether affected areas increase or decrease; if releases reduce, impacts should lessen accordingly.
The GISTDA spokesperson concluded by urging the public to rely on modern, accurate government tools and technology, to closely follow reliable news sources, verify information origins, and prepare accordingly if living in risk areas. People can monitor water situations and flood risk zones in real time via the “Check Water” app.