Torrential rain intensified across southern Taiwan on Sunday, August 23, with parts of Kaohsiung receiving more than 500 mm (19.7 in) in less than 24 hours as a persistent low-pressure zone and strong southwesterly flow focused tropical moisture over the region.
Ziguan and Mituo districts were among the hardest-hit areas, where rainfall totals surpassed the 500 mm threshold. Taiwan’s Central Weather Administration (CWA) escalated its warnings for Kaohsiung to the highest extreme-torrential-rain category as the downpours continued into Sunday evening.
Heavy flooding triggered by torrential rainfall in Tainan City, Taiwan 🇹🇼 pic.twitter.com/WFy4avC9jC
— Disaster News (@Top_Disaster) August 23, 2026
Flooding was reported across numerous parts of Kaohsiung. Roads disappeared beneath water, vehicles became stranded and floodwater entered some homes. The city’s light rail system also experienced disruption after a fallen tree affected operations.
Thousands Were Evacuated as Slopes Became Saturated
The danger extends well beyond urban flooding.
Authorities have issued numerous debris-flow and large-landslide alerts across southern Taiwan as days of rainfall saturate mountain slopes. More than 2,000 people were evacuated across Kaohsiung and Pingtung by Sunday as authorities moved residents away from vulnerable areas.
Kaohsiung also raised its emergency response to its highest level as conditions deteriorated. With additional heavy rain expected, schools and government offices will remain closed Monday in Kaohsiung, Tainan and Pingtung.
Coastal districts face an additional complication from high tide. When intense rainfall coincides with elevated sea levels, drainage toward the coast becomes less efficient, allowing floodwater to accumulate more rapidly in low-lying communities.
Torrential #rain hits southern #Taiwan
— Hans Solo (@thandojo) August 23, 2026
Kaohsiung, Tainan, and Pingtung report #flooding as low-pressure system brings heavy rain pic.twitter.com/e9IFldjegr
The extreme rainfall is being driven by a particularly moisture-rich atmospheric setup rather than a direct typhoon landfall.
A broad low-pressure zone combined with strengthening southwesterly winds is transporting deep tropical moisture toward southern Taiwan. The CWA warns that this pattern is highly favorable for short-duration intense rainfall, with Kaohsiung facing additional extreme totals through Monday.
As the moisture-laden southwesterly flow reaches Taiwan, convergence forces the air upward. The island’s steep mountains provide another powerful lifting mechanism, enhancing condensation and dramatically increasing rainfall on exposed slopes.
Persistent rain bands have also repeatedly crossed the same areas, allowing totals to accumulate far beyond what a single thunderstorm would normally produce.
The threat is not over. CWA forecasts indicate the strong southwesterly flow and low-pressure zone will continue influencing southern Taiwan into Monday, maintaining the risk of extreme rainfall, flash flooding, rapidly rising waterways, landslides and debris flows.
