Flash Flood in Pennsylvania, April 1 to 2, 1998

A series of thunderstorms with heavy rain moved across Chester County the afternoon and evening of the 1st and caused flooding of streams and creeks as well as considerable urban and poor drainage flooding. Small stream flooding began in Coatesville around 330 p.m. EST after 1.74 inches of rain fell within one hour. Numerous vehicles became trapped in underpasses. Successive showers and thunderstorms produced a widespread swath of heavy rain across the county with the largest storm totals in a band along the central third of the county from Atglen to Downingtown to Phoenixville. The runoff from the heavy rain also caused flooding along the larger creeks within the county. The East Branch of the Brandywine Creek near Downingtown reached its flood stage of 7 feet at 9 p.m. EST on the 1st. It crested at 9.0 feet at 11 p.m. EST and was back within bankfull at 130 p.m. EST on the 2nd. Farther downstream the Brandywine Creek at Chadds Ford briefly exceeded its 9 foot flood stage from 6 a.m. EST to 1030 a.m. EST on the 2nd. It crested at 9.2 feet at 730 a.m. EST. The Valley Creek near Valley Forge was above its estimated flood stage of 7 feet the evening of the 1st from 7 p.m. EST through 10 p.m. EST. It crested at 7.5 feet at 8 p.m. EST.Storm totals included 2.91 inches in Glenmoore, 2.37 inches in Valley Forge, 2.08 inches in Phoenixville and 1.83 inches in Honey Brook. Aside from a larger number than normal auto accidents, no other serious property or personal damage was reported.