Jun 27, 2025
A frontal boundary stationed across western Pennsylvania allowed for showers and thunderstorms to form during the morning hours of June 27, 2025. Favorable instability and marginal shear across central Pennsylvania allowed for thunderstorm development to begin by late morning and continue into the evening hours. Ample moisture in place allowed for heavy rainfall in nearly stationary storms across portions of the Lower Susquehanna Valley to prompt flash flooding across northern Lancaster County,
Source: NOAA National Weather Service Storm Events Database (event 1266687). Narrative written by NWS staff at the time of the event.
This event is one of many recorded floods in Lancaster County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.