The strong south to southwest winds preceding a cold frontal passage brought an unseasonably mild and moist air mass into Eastern Pennsylvania. This caused heavy rain to fall and caused poor drainage flooding as well as stream and river flooding in southeastern Pennsylvania on the 31st.  Most of the waterway flooding was minor and all creeks and  rivers were back within bankfull by the evening of the 31st. Event totals averaged 1.5 to 3.0 inches. The rain began during the second half of the afternoon on the 30th and fell at its heaviest during the early morning of the 31st as convective elements moved through eastern Pennsylvania. The rain ended around 7 a.m. EST on the 31st.

Flood in MONTGOMERY, PENNSYLVANIA
From 31-JAN-13 02:52:00 to 31-JAN-13 18:28:00 (EST-5)
Location: EAST GREENVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Schuylkill River at Norristown was above its 13 foot flood stage from 820 a.m. EST through 628 p.m. EST on the 31st. It crested at 13.99 feet at 130 p.m. EST. The East Branch of the Perkiomen Creek at Schwenksville had moderate flooding and was above its 7 foot flood stage from 440 a.m. EST through 103 p.m. EST on the 31st. It crested at 9.38 feet at 1030 a.m. EST. The Main Stem of the Perkiomen Creek at East Greenville was above its 4 foot flood stage from 252 a.m. EST through 955 a.m. EST on the 31st. It crested at 5.28 feet at 730 a.m. EST. Farther downstream, the Perkiomen Creek at Graterford was above its 11 foot flood stage from 513 a.m. EST through 131 p.m. EST on the 31st. It crested at 12.49 feet at 815 a.m. EST. The Wissahickon Creek at Fort Washington was above its 9 foot flood stage from 547 a.m. EST through 759 a.m. EST on the 21st. It crested at 9.58 feet at 645 a.m. EST. Event precipitation totals included 2.75 inches in Perkiomenville, 2.64 inches in Green Lane, 2.44 inches in Pottstown, 2.43 inches in Frederick, 2.37 inches in East Greenville, 2.09 inches in Gilbertsville, 1.62 inches in West Norriton, 1.60 inches in Blue Bell and 1.56 inches in Collegeville.

Flood in BUCKS, PENNSYLVANIA
From 31-JAN-13 02:30:00 to 31-JAN-13 05:49:00 (EST-5)
Location: KEELERSVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

The heavy rain concentrated the flooding in Upper Bucks County. In East Rockhill Township, flooding along the Threemile Run closed the intersection of Stone Edge and Threemile Run Road. In Sellersville, flooding along the East Branch of the Perkiomen Creek forced the closure of the intersection of Main and Walnut Streets. In Quakertown, creek flooding affected Ninth and Main Streets and West End Boulevard. The East Branch of the Perkiomen Creek at Dublin was above its 5 foot flood stage from 421 a.m. EST through 549 a.m. EST on the 31st. It crested at 5.23 feet at 445 a.m. EST. Event precipitation totals included 2.64 inches in Pennsburg, 2.33 inches in Springtown, 1.79 inches in Perkasie, 1.53 inches in Doylestown and 1.14 inches in Langhorne.

Flood in DELAWARE, PENNSYLVANIA
From 31-JAN-13 06:16:00 to 31-JAN-13 17:15:00 (EST-5)
Location: FLORIDA PARK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 1231 p.m. EST through 515 p.m. EST on the 31st. It crested at 9.20 feet at 219 p.m. EST. The Crum Creek at Newtown Square was above its 6 foot flood stage from 616 a.m. EST through 745 a.m. EST on the 31st. It crested at 6.28 feet at 700 a.m. EST. Event precipitation totals included 1.37 inches in Aston.

Flood in BERKS, PENNSYLVANIA
From 31-JAN-13 03:18:00 to 31-JAN-13 12:25:00 (EST-5)
Location: YELLOW HOUSE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Manatawny Creek near Spangsville had moderate flooding and was above its 6 foot flood stage from 318 a.m. EST through 1225 p.m. EST on the 31st. It crested at 7.43 feet at 715 a.m. EST. Event precipitation totals included 2.93 inches in Mohnton, 2.79 inches in Reading, 2.62 inches in Boyertown, 2.26 inches in Kutzville and 2.12 inches in Berne.

Flood in CHESTER, PENNSYLVANIA
From 31-JAN-13 02:53:00 to 31-JAN-13 17:15:00 (EST-5)
Location: COMPASS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The West Branch of the Brandywine Creek at Honey Brook was above its 7 foot flood stage from 253 a.m. EST through 1017 a.m. EST on the 31st. It crested at 8.93 feet at 6 a.m. EST. The main stem of the Brandywine Creek at Chadds Ford was above its 9 foot flood stage from 1231 p.m. EST through 515 p.m. EST on the 31st. It crested at 9.20 feet at 219 p.m. EST. The Valley Creek at Valley Forge was above its 7 foot flood stage from 355 a.m. EST through 409 a.m. EST on the 31st. It crested at 7.10 feet at 400 a.m. EST. The French Creek at Phoenixville was above its 8 foot flood stage from 402 a.m. EST through 115 p.m. EST on the 31st. It crested at 8.59 feet at 830 a.m. EST.
Event precipitation totals included 2.75 inches in Honey Brook, 2.23 inches in Glenmoore, 1.93 inches in Malvern, 1.62 inches in Nottingham and West Chester and 1.61 inches in Devon.

Flood in PHILADELPHIA, PENNSYLVANIA
From 31-JAN-13 09:45:00 to 31-JAN-13 12:19:00 (EST-5)
Location: MANAYUNK
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 945 a.m. EST through 1219 p.m. EST on the 31st. It crested at 5.23 feet at 1115 a.m. EST. Event precipitation totals included 1.28 inches in Wyndmoor, 1.18 inches in Rockledge and 0.94 inches at the Philadelphia International Airport. Heavier rain fell in upstream areas of the Wissahickon Basin in Montgomery County.