American Samoa's Tropical Cyclone Outlook 2024-2025

WSO Pago Pago Office Predicts a normal to BELOW normal Tropical Cyclone (TC) Season for 2024-25 for American Samoa Read More >

Flash Flood

Flooding that begins within 6 hours, and often within 3 hours, of the heavy rainfall (or other possible cause)

Flash floods are the most dangerous kind of floods, because they combine the destructive power of a flood with incredible speed. Flash floods occur when heavy rainfall exceeds the ability of the ground to absorb it, or when enough water accumulates for streams to overtop their banks, causing rapid rises of water in a short amount of time. They can happen within minutes of the causative rainfall, limiting the time available to warn and protect the public.

Flash Flood Terminology

Flash Flood Watch	Flash flooding is possible within the designated watch area -- Be alert !
Flash Flood Warning	Flash flooding has been reported or is imminent -- Take necessary precautions at once!
Small Stream Advisory	Flooding of small streams, roads and low-lying areas is occurring.
Flash Flood Statement	Follow-up information regarding flash flood event.