Tropical Storm — Riverside County Mountains, California

2023-08-20 · Riverside County Mountains, California

Event narrative

Tropical Storm Hilary produced widespread tropical storm-force winds across Southern California from early morning on August 20 through the evening. The following are the top wind gusts reported across the Riverside County Mountains:

Pine Cove Rocky Point: 62 MPH (3:00 PM 08/20)

Apple Canyon (SCE376): 60 MPH (3:30 PM 08/20)

Red Mountain (SCE248): 59 MPH (3:40 PM 08/20)

San Marcos 3: 58 MPH (4:17 PM 08/20)

Chimney Flats (SCE247): 56 MPH (12:00 PM 08/20)

Keen Ridge (SCE375): 55 MPH (3:20 PM 08/20)

Twin Pines (SCE035): 52 MPH (10:10 AM 08/20)

Anza: 51 MPH (2:54 PM 08/20)

Pine Cove (SCE1170): 48 MPH (8:20 AM 08/20)

Pine Cove Water Office: 45 MPH (3:45 PM 08/20)

Idyllwild (SCE002): 45 MPH (3:40 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 1129871. Narrative written by the NWS forecast office that issued the report.