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Flash Flood — Los Alamos, NM

Aug 21, 2011

The first day of flash flooding over the Las Conchas burn scar was widespread as weak upper level disturbances rounded the west side of the upper high. Early in the afternoon, showers and thunderstorms developed over the central and northern portions of the burn scar. These storms generally produced 1 to 2 inches of rainfall. Later in the afternoon and early evening, even stronger and very slow moving storms developed across the southern portions of the burn scar. Radar estimated 3 to 4 inches

Source: NOAA National Weather Service Storm Events Database (event 329121). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Los Alamos, NM

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

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