An intense low pressure system that moved through the Great Lakes on the 9th produced a strong southerly flow of moist air from the Gulf of Mexico and Atlantic Ocean. Rain, with some snow at the start, began falling during the late evening of the 8th and ended by Noon EST on the 9th across Berks County and Philadelphia and the nearby suburbs. The rain fell heavy at times between 5 a.m. EST and 9 a.m. EST on the 9th. Event precipitation totals averaged around two inches. The concentration of the heavy rain and some headwater snow melt in a relatively short period of time produced poor drainage flooding as well as flooding of some of the streams and creeks in the southeastern part of Pennsylvania.

Flood in DELAWARE, PENNSYLVANIA
From 09-DEC-09 07:27:00 to 09-DEC-09 23:08:00 (EST-5)
Location: CHADDS FORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Runoff from heavy rain caused poor drainage flooding and creek flooding in Delaware County. The main stem of the Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 4 p.m. EST through 1108 p.m. EST on the 9th. It crested at 9.76 feet at 815 p.m. EST. The Chester Creek in Chester was above its 8 foot flood stage from 754 a.m. EST through 1231 p.m. EST on the 9th. It crested at 9.72 feet at 945 a.m. EST. Crum Creek at Newtown Square was above its 6 foot flood stage from 727 a.m. EST through 1248 p.m. EST on the 9th. It crested at 7.38 feet at 930 a.m. EST. Event precipitation totals included 2.13 inches at the Philadelphia International Airport.

Flood in BERKS, PENNSYLVANIA
From 09-DEC-09 12:30:00 to 09-DEC-09 15:28:00 (EST-5)
Location: YELLOW HOUSE
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The combination of snow melt and heavy rain caused flooding along sections of the Manatawny Creek in Berks County. Poor drainage flooding also occurred. The Manatawny Creek at Spangville was above its 6 foot flood stage from 1230 p.m. EDT through 328 p.m. EDT on the 9th. It crested at 6.17 feet at 215 p.m. EST. Event precipitation totals included 1.43 inches in Kutztown, 1.36 inches in Mohnton, 1.34 inches in West Lawn, 1.19 inches in Fleetwood and 1.16 inches in Reading.

Flood in CHESTER, PENNSYLVANIA
From 09-DEC-09 07:05:00 to 09-DEC-09 23:08:00 (EST-5)
Location: CHADDS FORD JCT
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Runoff from melting snow and heavy rain caused poor drainage flooding and several creeks to flood in Chester County. The East Branch of the Brandywine Creek at Downingtown was above its 7 foot flood stage from 933 a.m. EST through 345 p.m. EST on the 9th. It crested at 9.86 feet at 1215 p.m. EST. The West Branch of the Brandywine Creek at Honey Brook was above its 7 foot flood stage from 1035 a.m. EST through 134 p.m. EST on the 9th. It crested at 7.31 feet.  The main stem of the Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 4 p.m. EST through 1108 p.m. EST on the 9th. It crested at 9.76 feet at 815 p.m. EST. The French Creek at Phoenixville was above its 8 foot flood stage from 835 a,m. EST through 1218 p.m. EST on the 9th. It crested at 8.41 feet at 945 a.m. EST. The Valley Creek at Valley Forge was above its 7 foot flood stage from 705 a.m. EST on the 9th through 1202 p.m. EST on the 9th. It crested at 7.83 feet. Event precipitation totals included 2.07 inches in Unionville, 2.03 inches in West Chester, 1.90 inches in Kenneth Square, 1.80 inches in Valley Forge, 1.75 inches in Downingtown and Nottingham, 1.67 inches in Glenmoore and 1.25 inches in Honey Brook.

Flood in BUCKS, PENNSYLVANIA
From 09-DEC-09 10:25:00 to 09-DEC-09 19:00:00 (EST-5)
Location: LANGHORNE
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The combination of snow melt and heavy rain caused poor drainage flooding and flooding along sections of the Neshaminy Creek. The Neshaminy Creek at Langhorne was above its 9 foot flood stage from 1025 a.m. EST through 7 p.m. EST on the 9th. It crested at 10.07 feet at 145 p.m. EST. Event precipitation totals included 2.15 inches in Bensalem and Penndel, 1.96 inches in Newtown, 1.86 inches in Langhorne, 1.69 inches in Doylestown and 1.63 inches in Perkasie.

Flood in MONTGOMERY, PENNSYLVANIA
From 09-DEC-09 07:44:00 to 09-DEC-09 17:13:00 (EST-5)
Location: EAST GREENVILLE
Flood cause: Heavy Rain / Snow Melt
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Runoff from snow melt and heavy rain caused poor drainage flooding as well as flooding along sections of the Perkiomen and Wisshaickon Creeks in Montgomery County. Pennsylvania State Routes 73 and 29 were flooded in Schwenksville near the East Branch of the Perkiomen Creek. An 80-year-old woman was rescued from Middle Creek Road in Douglass Township after becoming trapped.
The Wissahickon Creek at Fort Washington was above its 9 foot flood stage from 744 a.m. EST through 125 p.m. EST on the 9th. It crested at 10.89 feet at 1045 a.m. EST. The East Branch of the Perkiomen Creek at Schwenksville was above its 7 foot flood stage from 817 a.m. EST through 513 p.m. EST on the 9th. It crested at 9.8 feet at Noon EST. The main stem of the Perkiomen Creek at East Greenville was above its 4 foot flood stage from 914 a.m. EST through 210 p.m. EST on the 9th. It crested at 4.59 feet at 1215 p.m. EST.
Event precipitation totals included 2.10 inches in Ardmore, 1.93 inches in Greaterford, 1.91 inches in King of Prussia, 1.80 inches in Gilbertsville, 1.79 inches in Lansdale, 1.72 inches in Collegeville, 1.64 inches in Blue Bell and North Wales, 1.57 inches in Pottstown, 1,56 inches in Palm and 1.48 inches in Norristown.

Flood in PHILADELPHIA, PENNSYLVANIA
From 09-DEC-09 08:13:00 to 09-DEC-09 19:22:00 (EST-5)
Location: BUSTLETON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Runoff from heavy rain caused poor drainage flooding and creek flooding within Philadelphia. The Frankford Creek at Castor Avenue was above its 7 foot flood stage from 813 a.m. EST through 845 a.m. EST on the 9th. It crested at 7.36 feet at 830 a.m. EST. The Wissahickon Creek at its mouth with the Schuylkill River was above its 5 foot flood stage from 831 a.m. EST through 554 p.m. EST on the 9th. It crested at 6.17 feet at 3 p.m. EST. The Pennypack Creek at the Rhawn Street Bridge was above its 7 foot flood stage from 830 a.m. EST through 722 p.m. EST on the 9th. It crested at 8.71 feet at 130 p.m. EST. Event precipitation totals included 2.13 inches at the Philadelphia International Airport, 2.02 inches in Wyndmoor and Rockledge.