Flood, Guam
- When
- July 30, 12:00 AM SST to 4:00 AM SST
- Where
- Guam County, Central Portion
- Reported by
- OFFICIAL NWS OBS.
Flood in Guam, July 30, 1999
16 of an inch falling between 0400 and 1000. Upper level divergent winds combined with low level winds converging into the Tropical Depression 11W caused heavy showers to move across Guam.
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.
At the National Weather Service Office at Tiyan 0.62 of an inch of rain fell between Midnight and 0400 with an additional 0.16 of an inch falling between 0400 and 1000. Upper level divergent winds combined with low level winds converging into the Tropical Depression 11W caused heavy showers to move across Guam. Tropical Depression 11W formed well to the west of Guam on the 29th. Tropical Depression 11Wdeveloped from a circulation. This circulation was first observed on the 23rd near 5N 146E to the southwest of Chuuk. It continued to move west an eventually moved between Yap and Palau on the 27th, it was still a circulation at this time. On the 30th Tropical Depression 11W became TropicalStorm Olga. The storm was out over the ocean far from land. It's northward movement took pushed it out of the Guam Area of Responsibility on the morning of the 31st.
Event by event
1 flood. Local standard time, as filed.
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
- Damaging Winds and Lightning Strike in Wisconsin, July 30 to 31, 1999
- Hail and Damaging Winds in Ohio, July 30 to 31, 1999
- Heat in Alabama, July 30, 1999
- Heat in Arkansas, July 30, 1999
- Lightning Strike in Wisconsin, July 30, 1999
- Heat in Arkansas, July 30, 1999
- Damaging Wind in Wisconsin, July 30, 1999
- Flood and Hail in Iowa, July 30 to 31, 1999
- Flash Flood in Guam, July 30, 1999
- Tornadoes and Hail in Minnesota, July 30, 1999
- Hail and Damaging Winds in New York, July 30, 1999
- Damaging Winds in Kansas, July 30, 1999
More
Every storm in Guam in 1999Every state in 1999This day in weather historyWarnings in Guam, July 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: 5701321.