Flood in Guam, November 9, 1999

Name: Flood in Guam, November 9, 1999
Start: 1999-11-09T00:00
End: 1999-11-09T05:00
Location: Guam

November 9, 1999 · NWS GUA · 1 event in 1 county or zone

Upper level divergence on the back side of an upper level low enhanced shower activity across the Marianas Islands. This brought showers and thunderstorms to Guam between midnight and 0500.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

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 GUA wrote it up.

Upper level divergence on the back side of an upper level low enhanced shower activity across the Marianas Islands. This brought showers and thunderstorms to Guam between midnight and 0500. The heavier showers moved across southern Guam bringing brief periods of heavy rain to that area. An automated weather observing station in Merizo recorded 1.72 inches of rain between 0110 and 0450.

Event by event

1 flood. Local standard time, as filed.

Flood, Guam

When: November 9, 12:00 AM SST to 5:00 AM SST
Where: Guam County, Inarajan
Reported by: OFFICIAL NWS OBS.

What these are

Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

Every storm in Guam in 1999 Every state in 1999 This day in weather history Warnings in Guam, November 1999

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: 5721681.