Flash Flood — Riverside, California

2015-07-19 · near Desert Center, Riverside, California

Event narrative

Aided by lingering tropical moisture from former hurricane Dolores, intense thunderstorms with torrential rain developed near Desert Center during the afternoon hours on July 19th. Based on radar estimates, over 6 inches of rain fell over several hours along and just to the south of Interstate 10, just to the west of Desert Center. According to a trained weather spotter about 4 miles west of Desert Center, the eastbound lanes of Interstate 10 collapsed where they crossed a heavily flowing wash, and one vehicle drove into the hole in the collapsed bridge. The driver became trapped by crushed asphalt and needed to be rescued. The injured driver was extracted from his truck and taken to a local hospital. According to local law enforcement, Interstate 10 was closed in both directions; water was flowing over the highway and the on and off ramps were flooded. Traffic was backed up for miles and needed to be re-routed. Within a short distance of the collapsed bridge, water flowing through a wash and under the freeway severely eroded and compromised the integrity of a second bridge; the second bridge did not collapse however. Interstate 10 will be closed in both directions for quite some time, probably at least one week, as bridges on both sides of the freeway will need to be re-built. A Flash Flood Warning was issued for the area from 1621PST through 1915PST.

Wider weather episode

The combination of lingering tropical moisture from former hurricane Dolores and a weather disturbance moving into southern California led to intense thunderstorms with torrential rainfall across portions of eastern Riverside county during the afternoon hours on July 19th. A cluster of slow moving thunderstorms near and just to the west of Desert Center produced more than 6 inches of rain along Interstate 10; the heavy rain caused significant flash flooding which washed out the eastbound lanes of the freeway. At this location, the interstate crossed a wash, and the flowing water raging through the wash collapsed the bridge across it. One vehicle drove into the wash; fortunately the driver was rescued and there were no fatalities. In addition, the flooding also eroded the westbound lanes of the freeway and as a result, Interstate 10 was closed indefinitely in both directions.

View location on OpenStreetMap → (33.7106, -115.4938)

Source: NOAA Storm Events Database, event_id 579890. Narrative written by the NWS forecast office that issued the report.