WhereIsAtlas · Natural disaster

Tropical Storm Thelma (Uring, 1991)

The 'bagyo' that sent a wall of water through Ormoc City — one of the Philippines' deadliest storms

Concluded — Tropical Storm Thelma (known locally as Uring) struck the Philippines in November 1991, causing catastrophic flash floods in Ormoc City, Leyte, that killed over 5,000 people — one of the deadliest storms in Philippine history.

Tropical Storm Thelma, known in the Philippines as Uring, hit the central Philippines in November 1991. It was not the most powerful storm of the year, but it produced torrential rainfall over the hills above Ormoc City on the island of Leyte.

The result was a catastrophic flash flood. Muddy water and debris surged down the hillsides and through the low-lying city, sweeping away homes and streets — much of it with little warning. The flood killed over 5,000 people, making it one of the deadliest storms in Philippine history, despite being a relatively modest tropical storm by wind strength.

The Thelma disaster is often cited as a case study in how flash flooding — driven by extreme rainfall on deforested or densely populated slopes — can be far more deadly than the winds of a hurricane. It reshaped how the Philippines thought about flood risk and early warning.

Quick facts

Date
November 1991
Local name
Uring
Location
Ormoc City, Leyte
Killer
Catastrophic flash flood (not wind)
Deaths
5,000+
Significance
One of the deadliest storms in PH history
Lesson
Flash flood risk can exceed wind threat

Sources

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