Flash Flood — Lancaster, Pennsylvania

2025-07-31 · near Lancaster, Lancaster, Pennsylvania

Event narrative

High water flowing near Keller and Marshall avenues in Lancaster resulted in a water rescue.

Wider weather episode

A surface cold front was stationed near the Mason-Dixon line, with an area of surface low pressure developing and tracking across southern portions of central Pennsylvania. This brought increasing moisture across the area, with ample low-level and effective bulk shear allowing for multiple thunderstorms to develop during the morning and afternoon hours on July 31, 2025. Isolated thunderstorm development in Lancaster County began to intensity, with one thunderstorm producing multiple instances of trees and wires down in Lancaster County. Heavy rainfall continued into the afternoon hours, with flash flooding beginning to occur in Lancaster County and Little Conestoga Creek running out of its banks and closing numerous roadways. Multiple water rescues were also observed due to flash flooding throughout Lancaster County.

View location on OpenStreetMap → (40.0561, -76.3060)

Source: NOAA Storm Events Database, event_id 1278796. Narrative written by the NWS forecast office that issued the report.