Flash Flood Warning Issued for Parts of New Jersey and Pennsylvania
The National Weather Service in Mount Holly has issued a Flash Flood Warning for portions of New Jersey and Pennsylvania, effective until 12:00 PM EDT on September 13, 2026. Ongoing or imminent heavy rainfall is expected to cause flash flooding across the warned areas.
The warning, issued at 8:06 AM EDT, covers central Mercer County and southwestern Middlesex County in central and northern New Jersey, as well as southeastern Bucks, Delaware, southeastern Montgomery, and Philadelphia counties in southeastern Pennsylvania.
Doppler radar indicated heavy rain across the region, with accumulations of 0.5 to 1.5 inches already recorded. Forecasters expect additional rainfall rates of 0.5 to 1.5 inches per hour, meaning flash flooding is either ongoing or expected to begin shortly.
The hazardous conditions are expected to impact small creeks, streams, urban areas, highways, streets, underpasses, and other poor drainage or low-lying locations. Some specific areas that will experience flash flooding include Philadelphia, Trenton, Bensalem, Ewing, Chester, Princeton, Yeadon, Folcroft, Swarthmore, Hightstown, and Jenkintown.