The combination of a stalled frontal boundary, extending from the Pennsylvania/Maryland border eastward across southern New Jersey, and a series of upper level disturbances resulted in numerous slow-moving thunderstorms from the afternoon of the 22nd through the early morning of the 23rd. These thunderstorms produced torrential rain and some wind damage.
Storm total rainfall measurements ranged mainly between 2 and 7 inches across eastern Pennsylvania. Run-off from waves of heavy precipitation resulted in areas of poor drainage and roadway flooding, with some creeks and streams also overflowing their banks.
In addition, the combination of the heavy rain and higher than normal astronomical tides caused minor tidal flooding along the tidal Delaware River during the early morning high tide cycles on the 23rd and lingered into the early morning high tide cycle on the 24th. In Philadelphia, the highest tide reached 8.76 feet above mean lower low water on the 23rd. Minor tidal flooding starts at 8.2 feet above mean lower low water.

Flash Flood in BERKS, PENNSYLVANIA
From 22-JUL-13 23:15:00 to 23-JUL-13 01:30:00 (EST-5)
Location: WYOMISSING JCT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy rain fell through the night of the 22nd and caused poor drainage and small stream flash flooding to occur during the early morning of the 23rd. Wyomissing Creek was quickly out of its banks. Flooding was reported at the Cambridge Commons Apartments Complex, with water reported in the maintenance building. Flooding was also reported on Pennsylvania State Route 12 approaching Reading. Event precipitation totals included 6.70 inches in Kutztown, 4.75 inches in Boyertown, 4.21 inches in Bernville, 2.29 inches in Fleetwood and 2.23 inches in Oley.

Flash Flood in CHESTER, PENNSYLVANIA
From 23-JUL-13 00:15:00 to 23-JUL-13 02:30:00 (EST-5)
Location: WARWICK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Heavy rain fell through the night of the 22nd and caused poor drainage and small stream flash flooding to occur during the early morning of the 23rd. Several roads were reported to be flooded across Chester County. Event precipitation totals included 1.58 inches in West Grove.

Flash Flood in MONTGOMERY, PENNSYLVANIA
From 23-JUL-13 01:15:00 to 23-JUL-13 04:00:00 (EST-5)
Location: FRANCONIA
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Heavy rain fell through the night of the 22nd and caused poor drainage and small stream flash flooding to occur during the early morning of the 23rd. Several roads around Schwenksville were reported to be flooded out. Cars were submerged within flood waters in Pottstown. No serious injuries were reported. Event precipitation totals included 3.32 inches in Gilbertsville, 2.90 inches in Blue Bell, 2.69 inches in North Wales, 2.57 inches in Kulpsville, 2.37 inches in Hatfield and 2.33 inches in Pottstown.

Flash Flood in PHILADELPHIA, PENNSYLVANIA
From 23-JUL-13 01:42:00 to 23-JUL-13 04:00:00 (EST-5)
Location: OVERBROOK
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Heavy rain fell through the night of the 22nd and caused urban and poor drainage flash flooding. Several areas of significant flooding were reported on the Schuylkill Expressway. Significant flooding was also reported on Broad Street in South Philadelphia under Interstate 95, with vehicles trapped. The water level was reported to be nearly up to the car windows. Deep standing water occurred on Interstate 95. The heavy rain flooded sections of the 8th and Market PATCO Commuter rail line stop. The Pennypack Creek at the Rhawn Street Bridge was above its 7 foot flood stage from 242 a.m. EDT through 255 a.m. EDT on the 23rd. It crested at 7.25 feet at 245 a.m. EDT. Event precipitation totals included 1.50 inches in Northeast Philadelphia, 1.29 inches in Rockledge and 1.18 inches in Northwest Philadelphia.