Tropical Storm — Santa Ana Mountains and Foothills, California

2023-08-20 to 2023-08-21 · Santa Ana Mountains and Foothills, California

Event narrative

Tropical Storm Hilary produced widespread tropical storm-force winds across Southern California from early morning on August 20 through the early overnight hours into August 21. The following are the top wind gusts reported across the Santa Ana Mountains and Foothills:

Santiago Peak: 65 MPH (1:45 PM 08/20)

Corona RAWS: 56 MPH (12:11 AM 08/21)

Fremont Canyon: 56 MPH (7:51 PM 08/20)

Pleasants Peak (SCE1534): 55 MPH (12:20 PM 08/20)

Pleasants Peak: 55 MPH (9:56 AM 08/20)

Case Springs: 54 MPH (11:22 PM 08/20 )

Temescal: 53 MPH (12:41 AM 08/21)

Lake Elsinore Vista (SCE084): 52 MPH (6:50 PM 08/20)

Camp Pendleton: 49 MPH (11:28 AM 08/20)

El Cariso RAWS: 48 MPH (11:20 PM 08/20).

Wider weather episode

Tropical Storm Hilary made landfall across northern Baja California on August 20, and moved through Southern California that afternoon and evening. Torrential rainfall occurred across mountain and desert communities, resulting in catastrophic flash flooding and debris flows, damaged railways and bridges, and the closing of major interstates including I-8 in San Diego County and I-10 in Riverside County. Widespread tropical-storm force winds were recorded across much of Southern California.

Source: NOAA Storm Events Database, event_id 1129863. Narrative written by the NWS forecast office that issued the report.