Flash Flood — Bucks, Pennsylvania

2005-10-08 · near Northwest Portion, Bucks, Pennsylvania

Wider weather episode

The combination of a very slow moving cold front and copious moisture from the remnants of Tropical Storm Tammy produced persistent and very heavy rain across Bucks County from the early morning into the afternoon of the 8th. Storm totals averaged from four to six inches with amounts exceeding eight inches toward the Lehigh Valley. The heavy rain caused widespread poor drainage flooding as well as flooding along the smaller creeks in the county. The flooding also resulted in the death of a 19-year-old woman in Milford Township. She lost control of her vehicle while trying to cross a flooded road over the Molasses Creek. Her vehicle hit a guardrail and flipped into the flooded creek. Dozens of roads were impassable with the greatest reported closures in Lower Makefield, Bridgeton and New Hope. The Neshaminy Creek at Langhorne was above its 9 foot flood stage from 1026 p.m. EDT on the 8th through 828 a.m. EDT on the 9th. It crested at 11.74 feet at 445 a.m. EDT on the 9th. Flooding also occurred early that evening at the confluence of the Neshaminy Creek and Delaware River in Bristol and Bensalem Townships at the time of the high tide. Storm totals included 7.52 inches in Sellersville, 6.32 inches in Furlong, 6.01 inches in Doylestown, 5.99 inches in Perkasie, 5.98 inches in Neshaminy Falls and 4.44 inches in Southampton. This heavy rain helped the state of Pennsylvania have its second wettest October on record dating back to 1895. The statewide average precipitation total was 6.49 inches, 3.31 inches wetter than normal. Only 1976 (6.59 inches) was wetter. October 2005 was the wettest October on record at the Philadelphia International Airport with a precipitation total of 8.68 inches, 5.93 inches wetter than normal and surpassed the previous record by 2.02 inches. The cold front moved from near Pittsburgh, Pennsylvania at 8 p.m. EDT on the 7th, to the Susquehanna Valley in Pennsylvania at 2 a.m. EDT on the 8th, to the Poconos and Berks County in Pennsylvania and just west of Chesapeake Bay in Maryland at 8 a.m. EDT on the 8th. The cold front stalled as waves of low pressure road northeast along it. At 2 p.m. EDT on the 8th, the cold front just edged into northwestern New Jersey and the Philadelphia northwest suburbs and was still west of Chesapeake Bay in Maryland. At 8 p.m. EDT that evening the cold front barely moved into the Philadelphia New Jersey suburbs and the Delmarva Peninsula. The cold front and waves of low pressure cleared the Delaware and New Jersey coasts between Midnight EDT and 2 a.m. EDT on the 9th. The slow movement and stalling coupled with an unstable air mass and tropical moisture associated with Tammy helped enhance the torrential downpours. The flooding would have been even worse if not for the unseasonably dry weather that preceded this event from the middle of August.

View location on OpenStreetMap → (40.3167, -75.0667)

Source: NOAA Storm Events Database, event_id 5477834. Narrative written by the NWS forecast office that issued the report.