Jun 4, 2010
A deep low pressure system anchored in the Gulf of Alaska and a zonal flow pattern across the Pacific Northwest and Intermountain West provided the right ingredients for a sustained moisture plume which produced convection and periods of moderate to heavy rain over a three day period causing flooding and flash flooding, and severe thunderstorms across Southeast Oregon and Southwest Idaho.
Source: NOAA National Weather Service Storm Events Database (event 241734). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Washington County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.