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Flash Flood — Riverside, CA

Aug 30, 2021

An upper level low sitting off the coast of the northern Baja Peninsula promoted diffluent flow over southeast California. The moist, unstable environment combined with adequate forcing mechanisms allowed for strong to severe thunderstorms to develop. High DCAPE values across the region helped enhance the threat for damaging winds resulting from downbursts. Thunderstorms initially developed in southwest Arizona before producing a westward moving outflow boundary. Several observations recorded gu

Source: NOAA National Weather Service Storm Events Database (event 983872). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Riverside, CA

This event is one of many recorded floods in Riverside County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

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