Thunderstorms redeveloped during the afternoon and moved slowly west southwest down the valley. Rainfall rates were high with over an inch of rain falling in less than a half hour.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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.
The episode as NWS SGX wrote it up.
Thunderstorms redeveloped during the afternoon and moved slowly west southwest down the valley. Rainfall rates were high with over an inch of rain falling in less than a half hour. Radar rainfall estimates were near three inches. As a result creeks and streams feeding into Mill Creek rapidly filled and created a 25 foot high wall of water, rocks, and mud. Seven homes were destroyed, 11 sustained moderate to severe damage, and 35 others had minor damage. Roads were covered with 10 feet of rocks, mud, and debris. Flash flood waters continued to move down Mill Creek and into the Santa Ana River, causing road flooding in Redlands .
The Edwards AFB radar (KEYX), 129 km away, was scanning. The volume nearest the first event began at 23:18 UTC.
1 flash flood, 1 flood. Local standard time, as filed.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flash Flood, San Bernardino | 1999-07-11 | 36 | Female | Permanent Home | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 1999Every state in 1999This day in weather historyWarnings in California, July 1999
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: 5706929, 5706930.