25 November 2025 – Key Causes of This Year’s Severe Flooding in Hat Yai
“Lingering Rainfall” Phenomenon:
The primary cause of the severe flooding in Hat Yai this year is the phenomenon known as “lingering rainfall”—intense rain that remains stationary over the same area for an extended period. Unlike previous years, heavy rainfall persisted continuously from 22–24 November.
Critical Rainfall Volume:
Accumulated rainfall in Hat Yai exceeded 700–800 millimeters, while Songkhla Province—especially Thepha District—recorded up to 800 millimeters of accumulated rain.
Daily Rainfall Intensity:
Although the total seasonal rainfall may not be significantly higher than in previous years, the severity stems from exceptionally high daily accumulations, surpassing 300 millimeters per day, overwhelming the drainage capacity.
Additional Contributing Factors
Water Flow and Geography:
Runoff from surrounding areas converged into Hat Yai, causing major canals that drain into Songkhla Lake and its tributaries to overflow to critical levels. Urban expansion has also reduced natural water-absorption zones.
Mountain Runoff:
In addition to rainfall within the city, large volumes of water flowed down from surrounding mountains, intensifying the situation.
Outlook and Response
Forecast:
If rainfall decreases from 25 November onward, water levels are expected to stabilize and recede to normal within 5–7 days.
Natural Warning Signs:
Although lingering rainfall is uncommon, climate change has increased the likelihood of such extreme weather events. Residents should remain cautious even if such flooding has not occurred for 20–30 years.
Management Measures:
Authorities must strengthen coordination between central and local agencies to plan evacuations for vulnerable groups and deploy personnel efficiently to high-risk zones.