Flash Flood — Lycoming, Pennsylvania

2025-06-26 · near Lairdsville, Lycoming, Pennsylvania

Event narrative

Heavy rain resulted in flash flooding and water covering Route 118 in Lairdsville.

Wider weather episode

Hot and humid conditions under the influence of a lee-side trough allowed for scattered thunderstorm development during the afternoon and evening hours of June 26, 2025. Ample moisture in place across the region (PWATs in 1.75 to 2.00 range), coupled with overly favorable instability (CAPE in the 2000-3000 J/kg range) allowed for pulse thunderstorms to push up towards severe limits and trend downward without sufficient shear in place across central Pennsylvania. Severe thunderstorms across south-central and southeastern Pennsylvania produced scattered instances of tree damage. This lack of shear also allowed for thunderstorms, producing efficient rainfall rates exceeding one inch per hour, to stall out and/or move slowly, prompting isolated instances of flash flooding across Lycoming County.

View location on OpenStreetMap → (41.2292, -76.6141)

Source: NOAA Storm Events Database, event_id 1266686. Narrative written by the NWS forecast office that issued the report.