Friday, November 21, 2025

Flood Advisories and Flash Flood Warnings Issued for Pasadena as Heavy Rain Pounds Los Angeles County

The National Weather Service in Los Angeles/Oxnard extended multiple flood advisories and flash flood warnings early Friday morning as heavy rain swept across Los Angeles County, with Pasadena among the communities under alert.

At 2:47 and 2:49 a.m., the NWS issued two Flood Advisories warning of urban and small stream flooding caused by excessive rainfall. Doppler radar indicated heavy rain, prompting the extension of advisories until 6 a.m. PST. Impacts include minor flooding in low?lying streets, water ponding in urban areas, and possible rockslides or mudslides in hillside terrain.

By 3:09 a.m. and again at 3:59 a.m., forecasters extended Flash Flood Warnings for both Southwestern Los Angeles County and South Central Los Angeles County. Radar and automated gauges showed moderate to heavy showers and thunderstorms. Rainfall rates of 0.4 to 0.8 inches per hour were observed, with flash flooding ongoing or imminent. Hazards were described as “flash flooding caused by thunderstorms” and “flash flooding, along with rock slides and mudslides, caused by thunderstorms.”

The Weather Service cautioned residents to avoid flooded roads and emphasized: “Turn around, don’t drown when encountering flooded roads. Most flood deaths occur in vehicles.” Officials added that nighttime conditions make flooding harder to recognize.

Pasadena residents are advised to remain alert for water over roadways and possible debris flows in foothill neighborhoods.

Other locations named in the advisories and warnings include Altadena, La Cañada Flintridge, Glendale, and Mount Wilson.