American Samoa, 2020

Flash Flood and Heavy Rain in American Samoa, December 10 to 18, 2020

December 10 to 18, 2020 · NWS ASO · 2 events in 1 county or zone

The Active SPCZ, which formed Tropical Cyclone Zasu as well as YASA produced a week downpour of rain and strong winds for the Islands of American Samoa.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
$120,000
Crop damage
$50,000
Events
2

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS ASO wrote it up.

The Active SPCZ, which formed Tropical Cyclone Zasu as well as YASA produced a week downpour of rain and strong winds for the Islands of American Samoa.

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 heavy rain, 1 flash flood. Local standard time, as filed.

Heavy Rain, Tutuila

When
December 10, 7:00 PM SST to 8:00 PM SST
Where
Tutuila County, 6.02 mi W of Pago Pago
Property damage
$20,000
Reported by
Broadcast Media
Coordinates
-14.302, -170.690

Vehicle overturns under wet road conditions between the villages of Faganeanea and Matu'u.

Flash Flood, Tutuila

When
December 15, 12:00 AM SST to December 18, 11:00 PM SST
Where
Tutuila County, 7.05 mi NW of Vaitogi to 4.09 mi NNW of Vaitogi
Cause
Heavy Rain
Property damage
$100,000
Crop damage
$50,000
Reported by
Broadcast Media
Coordinates
-14.330, -170.776

After a week long weather event, WSO Pago Pago finally broke its annual rainfall record since 1981, standing near 165 inches of rain. The new record of 189.90 inches took place during this event. Multiple reports from around the Island of clogged drainages, formation of potholes, and business being affected for the Holidays were called in. Reports of flash flooding in low lying areas were mainly reported in the dense populated districts of Tualauta and Tualatai.

What these are

Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in American Samoa in 2020Every state in 2020This day in weather historyWarnings in American Samoa, December 2020

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 937316, 937317.