Jul 3, 2009
A very moist southerly flow was in place over the area. The atmospheric moisture content was almost twice the normal value for early July. The flow was such that thunderstorm movement was slow, subjecting locations to very heavy rainfall for long periods of time. Occasional wet microbursts were also observed.
Source: NOAA National Weather Service Storm Events Database (event 191468). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Sierra County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.