Heavy rain and flooding affected most of Eastern Pennsylvania on the 11th and 12th. Rain began during the afternoon of the 10th and continued through the 11th into the early morning on the 12th. Rain fell at its heaviest from the afternoon of the 11th until just after Midnight EST on the 12th. Event precipitation totals averaged two to four inches.
The heavy rain and flooding were caused by a low pressure system that developed along the Gulf Coast States on the 10th. This intensifying low pressure system moved northeast from Alabama on the morning of the 11th, to central North Carolina early in the evening on the 11th to near Bridgeport, Connecticut at 7 a.m. EST on the 12th.

Flood in PHILADELPHIA, PENNSYLVANIA
From 11-DEC-08 22:39:00 to 12-DEC-08 10:30:00 (EST-5)
Location: BUSTLETON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Wissahickon Creek at its mouth was above its 5 foot flood stage from 1 a.m. EST through 1030 a.m. EST on the 12th. It crested at 5.79 feet at 615 a.m. EST. The Pennypack Creek at the Rhawn Street Bridge was above its 7 foot flood stage from 1039 p.m. EST on the 11th through 753 a.m. EST on the 12th. It crested at 8.67 feet at 415  a.m. EST on the 12th.
There was also minor tidal flooding at the time of the early afternoon high tide along the Delaware River and its tidal tributaries on the 12th. The afternoon high tide in Philadelphia reached 8.44 feet above mean lower low water. Minor tidal flooding starts at 8.2 feet above mean lower low water.
Event precipitation totals included 3.51 inches at the Philadelphia International Airport, 3.30 inches in Pine Valley and 3.27 inches at the Northeast Philadelphia Airport.

Heavy Rain in MONROE, PENNSYLVANIA
From 11-DEC-08 14:00:00 to 12-DEC-08 01:00:00 (EST-5)
Location: LONG POND
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

In the valleys, plain heavy rain fell in the county. Event precipitation totals included 3.43 inches in Mount Pocono.

Flood in DELAWARE, PENNSYLVANIA
From 12-DEC-08 01:57:00 to 12-DEC-08 16:08:00 (EST-5)
Location: RIDLEY PARK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Main Stem of the Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 1010 a.m. EST through 408 p.m. EST on the 12th. It crested at 9.66 feet at 1 p.m. EST. The Crum Creek at Newtown Square was above its 6 foot flood stage from 157 a.m. EST through 321 a.m. EST on the 12th. It crested at 6.28 feet at 230 a.m. EST.
There was also minor tidal flooding at the time of the early afternoon high tide along the Delaware River and its tidal tributaries on the 12th. The afternoon high tide in Philadelphia reached 8.44 feet above mean lower low water. Minor tidal flooding starts at 8.2 feet above mean lower low water.
Event precipitation totals included 2.83 inches in Drexel Hill.

Flood in NORTHAMPTON, PENNSYLVANIA
From 12-DEC-08 02:00:00 to 12-DEC-08 23:59:00 (EST-5)
Location: ODENWELDER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

The Lehigh River overflowed onto Lehigh Drive at Adamson Street in Easton and West Easton. The road was closed through the night of the 12th.
Event precipitation totals included 3.82 inches in Martins Creek, 3.26 inches in Glendon and 2.76 inches in Nazareth.

Flood in BERKS, PENNSYLVANIA
From 12-DEC-08 02:03:00 to 12-DEC-08 09:27:00 (EST-5)
Location: EARLVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Creek flooding occurred along the Monocacy Creek and closed Limekiln Road in Amity Township. The Manatawny Creek at Spangville was above its 6  foot flood stage from 203 a.m. EST through 947 a.m. EST on the 12th. It crested at 6.49 feet at 7 a.m. EST.
Event precipitation totals included 3.50 inches in Kutztown, 3.48 inches in West Lawn, 3.42 inches in Bernville and 2.81 inches in Reading. The heavy rain during this December caused it to be the tied for the sixth wettest December on record in Reading (6.22 inches).

Flood in MONTGOMERY, PENNSYLVANIA
From 11-DEC-08 23:12:00 to 12-DEC-08 11:12:00 (EST-5)
Location: TRAPPE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The East Branch of the Perkiomen Creek at Schwenksville was above its 7 foot flood stage from 1117 p.m. EST on the 11th through 1039 a.m. EST on the 12th. It crested at 9.38 feet at 400 a.m. EST on the 12th.   The Main Stem of the Perkiomen Creek at East Greenville was above its 4 foot flood stage from 1210 a.m. EST through 758 a.m. EST on the 12th. It crested at 5.03  feet at 515 a.m. EST. Farther downstream, The Main Stem of the Perkiomen Creek at Graterford was above its 11 foot flood stage from 153 a.m. EST through 1112 a.m. EST on the 12th. It crested at 12.91  feet at 5 a.m. EST. The Wissahickon Creek at Fort Washington was above its 9 foot flood stage from 1112 p.m. EST on the 11th through 555 a.m. EST on the 12th. It crested at 10.35  feet at 2 a.m. EST on the 12th.
Event precipitation totals included 3.47 inches in Rockledge, 3.36 inches in Bala Cynwyd. 3.17 inches in Collegeville, 3.13 inches in Pottstown and 2.98 inches in Hatfield.

Flood in CHESTER, PENNSYLVANIA
From 12-DEC-08 01:05:00 to 12-DEC-08 16:08:00 (EST-5)
Location: PERKIOMEN JCT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The East Branch of the Brandywine Creek at Downingtown was above its 7 foot flood stage from 232  a.m. EST through 854 a.m. EST on the 12th. It crested at 9.37 feet at 646 a.m. EST. The West Branch of the Brandywine Creek at Honey Brook was above its 7 foot flood stage from 252 a.m. EST through 724 a.m. EST on the 12th. It crested at 7.37 feet at 530 a.m. EST. The Main Stem of the Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 1010 a.m. EST through 408 p.m. EST on the 12th. It crested at 9.66 feet at 1 p.m. EST. The French Creek at Phoenixville was above its 8 foot flood stage from 105 a.m. EST through 618 a.m. EST on the 12th. It crested at 8.77 feet at 230 a.m. EST.
Event precipitation totals included 2.58 inches in West Chester and 2.53 inches in East Nantmeal.

Flood in BUCKS, PENNSYLVANIA
From 12-DEC-08 02:00:00 to 12-DEC-08 09:00:00 (EST-5)
Location: NEWTOWN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The main stem of the Neshaminy Creek flooded. The heavy rain also caused another section of the Delaware Canal wall to collapse just south of the Groundhog Lock between Raubsville and Reigelsville on the berm side of the waterway.
Event precipitation totals included 3.46 inches in Pennsburg, 3.19 inches in Newtown, 3.08 inches in Penndel and 2.65 inchs in Doylestown.

Flood in CARBON, PENNSYLVANIA
From 12-DEC-08 02:00:00 to 12-DEC-08 09:00:00 (EST-5)
Location: LEHIGHTON CARBON ARP
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Heavy plain rain fell in the valleys. Flooding was reported along Mahoning Creek along the border of West Penn Township in Schuylkill County and Mahoning Township in Carbon County. Flood waters reached to the lawns of homes.
Event precipitation totals included 3.62 inches in Bowmanstown, 3.56 inches in Jim Thorpe, 3.25 inches in Lehighton and 3.21 inches in Palmerton.

Heavy Rain in LEHIGH, PENNSYLVANIA
From 11-DEC-08 14:00:00 to 12-DEC-08 01:00:00 (EST-5)
Location: JACKSONVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Event precipitation totals included 3.58 inches in Fogelsville. 3.49 inches in Schnecksville and 3.30 inches at the Lehigh Valley International Airport.