Dec 22, 2018
Following immediately on the heels of the system that produced flooding on the 20th in VA, another wave of low pressure tracked up along the spine of the Appalachians on the 21st. Showers and thunderstorms moved across the area during the afternoon hours of the 21st, locally producing an additional 1-2 inches of rain on top of previously saturated soils. This rainfall eventually led to some larger-stem river flooding on the 22nd and 23rd as the runoff drained downstream.
Source: NOAA National Weather Service Storm Events Database (event 806306). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Montgomery County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.