Snow fell across Eastern Pennsylvania from the late afternoon of the 11th into the early morning of the 12th. Snowfall averaged 4 to 7 inches with the highest amounts around the local Philadelphia area.  Snow began falling throughout Eastern Pennsylvania during the late afternoon and early evening on the 11th. The snow fell at its heaviest between 8 p.m. EST and Midnight EST. The snow ended around 2 a.m. EST on the 12th in the Philadelphia area and between 4 a.m. and 5 a.m. EST on the 12th in the Lehigh Valley and the Poconos.

Many schools in the local Philadelphia area closed, among them were Philadelphia's public and Archdiocesan schools. Some others, particularly in Philadelphia's western suburbs had delayed openings. Major roadways were cleared by the morning commute on the 12th and Philadelphia ended its snow emergency as of 9 a.m. EST.  The snow came as close to a perfect storm as could be expected.  Most were home and off the roads by the time the heavier snow started. The snow ended early, and plow crews were able to get their job done easily. There were no major accidents, and many main roads were just wet by the start of the morning commute. In and around Philadelphia, SEPTA reported disruptions and detours on some bus routes and delays of up to 20 minutes on Regional Rail lines. Philadelphia International Airport remained open all night but 120 flights were canceled on the 12th, largely due to the snow elsewhere. About 120 people were stranded overnight at the airport, compared to 1,200 after the December 26th winter storm. All four runways were expected to be cleared by Noon EST on the 12th.
Representative snowfall included 6.6 inches in Doylestown (Bucks County), 6.2 inches in Drexel Hill (Delaware County) and Rockledge (Philadelphia County), 6.0 inches in Ambler (Montgomery County) and Newtown (Bucks County), 5.9 inches in Bensalem (Bucks County), 5.8 inches in Glenmoore (Chester County) and Forks Township (Northampton County), 5.5 inches in Boothwyn (Chester County), 5.4 inches in Wynnewood (Montgomery County), 5.2 inches at the Philadelphia International Airport, 5.0 inches in East Nantmeal (Chester County), Morganville (Berks County), Glendon (Northampton County), Royersford and Lansdale (Montgomery County) and Lehighton (Carbon County), 4.8 inches in Gilbertsville (Montgomery County), 4.7 inches in Exton (Chester County), 4.6 inches at the Lehigh Valley International Airport, 4.5 inches in Palmerton (Carbon County) and Emmaus (Lehigh County), 4.4 inches in Martins Creek (Northampton County), 4.3 inches in Tobyhanna (Monroe County) and 4.0 inches in Bechtelsville (Berks County)
The snow was caused by a low pressure system that formed in the northwestern Gulf of Mexico on the 9th. It moved east across the northern Gulf of Mexico and passed across northern Florida overnight on the 10th and turned to the northeast. At 7 a.m. EST on the 11th, the low pressure system was located just off the southern North Carolina coast, near Wilmington. It continued to move northeast and at 7 p.m. EST on the 11th was located just east of Elizabeth City, North Carolina. At 1 a.m. EST on the 12th it started to intensify rapidly and was about 100 miles east of Atlantic City, New Jersey. At 7 a.m. EST on the 12th, the low pressure system (now 986 millibars and a 24 millibar drop in 12 hours) reached southeast Massachusetts. Its later intensification than the Boxing Day Blizzard on December 26th and overall faster movement kept snowfall totals in the single numbers.

Winter Weather in BERKS, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 02:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in CHESTER, PENNSYLVANIA
From 11-JAN-11 16:00:00 to 12-JAN-11 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in MONTGOMERY, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LEHIGH, PENNSYLVANIA
From 11-JAN-11 19:00:00 to 12-JAN-11 05:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 11-JAN-11 19:00:00 to 12-JAN-11 05:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in MONROE, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 05:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in CARBON, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 05:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in PHILADELPHIA, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in BUCKS, PENNSYLVANIA
From 11-JAN-11 18:00:00 to 12-JAN-11 04:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in DELAWARE, PENNSYLVANIA
From 11-JAN-11 17:00:00 to 12-JAN-11 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter