Heavy snow fell across east central and southeast Pennsylvania on the 21st and caused scores of accidents and tremendous traffic tie-ups on the afternoon of the 21st as well as least one storm related death.  Hundreds of flights were cancelled at the Philadelphia International Airport and many civic events were cancelled. An 87-year-old man in Wallingford (Delaware County) died after shoveling snow.
The heavy snow was caused by a quick moving clipper system tracked out of the Great Lakes region and began transferring its energy to the developing coastal low, resulting in rapid intensification. This strengthening low pressure moved northeast along the frontal boundary through the afternoon of the 21st, allowing multiple bands of heavy snow to traverse across portions of southeastern Pennsylvania. By late that day, the coastal low emerged east of the Delmarva Peninsula and quickly moved off towards New England, bringing an end to the snow from west to east across the region during the evening to overnight of the 21st to 22nd.
Along and near the Interstate 95 corridor, temperatures were cold enough for rapid accumulation, and a narrow band of heavy snow developed in this vicinity.  Within this general area, snowfall rates reached 2 to 3 inches per hour for a time during the midday hours of the 21st. Another band of heavy snow developed during the evening of the 21st over the northwestern Philadelphia suburbs. Snowfall totals ranged from around 12 inches  in the local Philadelphia area, 6 to 10 inches in the Philadelphia northwest suburbs, around 6 inches in the Lehigh Valley and Berks County and 1 to 4 inches in the Poconos.
In the greater Philadelphia area, the heavy banding snow led to the early dismissal of businesses, closing of malls and government offices and any schools that were open. This led to tremendous delays on roadways as traffic congestion complicated snow removal activities. Two hour or long commutes were common. The snow caused delays on SEPTA commuter rail service and forced the suspension or re-routing of about 30 bus routes.  Philadelphia International Airport managed to keep one runway open, but hundreds of flights were cancelled nonetheless. About 155 passengers spent the night at the airport. The Philadelphia Flyers-Carolina Hurricanes NHL hockey game was postponed. The effects of the heavy snow in southeast Pennsylvania continued the next day. Schools were closed. About 100 flights were cancelled at the Philadelphia International Airport. Major tourist attractions in Philadelphia were closed.
Representative snowfall totals included 13.9 inches in Clifton Heights (Delaware County), 13.5 inches at the Philadelphia International Airport (Philadelphia County), 13.2 inches in Folsom (Delaware County), 12.5 inches in Rockledge (Philadelphia County) and in Fox Chase (Philadelphia County) and also in Drexel Hill (Delaware County), 12.0 inches in Norwood (Delaware County) and in Lower Moreland Township (Montgomery County) and also in Wynnewood (Montgomery County), 11.5 inches in Yardley (Bucks County), 10.7 inches in Langhorne (Bucks County), 10.3 inches in North Wales (Montgomery County), 10.1 inches in King of Prussia (Montgomery County), 10.0 inches in East Nantmeal (Chester County), 9.5 inches in East Coventry Township (Chester County) and in Maple Glen (Montgomery County), 9.2 inches in Furlong (Bucks County), 9.1 inches in Graterford (Montgomery County), 9.0 inches in Hilltown Township (Bucks County) and in Spring City (Chester County), 8.7 inches in West Caln Township (Chester County), 8.5 inches in Morrisville (Bucks County), 7.8 inches in Exton (Chester County), 7.3 inches in Souderton (Montgomery County), 6.5 inches in Mohnton (Berks County), 6.0 inches in Wernersville (Berks County) and in Huffs Church (Berks County), 5.7 inches at the Lehigh Valley International Airport in Allentown (Lehigh County), 5.5 inches in Forks Township (Northampton County), 5.1 inches in Fleetwood (Berks County), 5.0 inches in Glendon (Northampton County), 4.5 inches in Reading (Berks County) and in Alburtis (Berks County), 4.3 inches in Slatington (Lehigh County), 4.2 inches in New Tripoli (Lehigh County), 3.5 inches in Nesquehoning (Carbon County), 3.3 inches in Albrightsville (Carbon County), 3.0 inches in Kidder Township (Carbon County) and in Bushkill Township (Northampton County), 2.8 inches in Martins Creek (Northampton County), 2.3 inches in Lehighton (Carbon County), 2.2 inches in Saylorsburg (Monroe County), 1.5 inches in East Stroudsburg (Monroe County), and 1.3 inches in Marshalls Creek (Monroe County).

Heavy Snow in DELAWARE, PENNSYLVANIA
From 21-JAN-14 09:20:00 to 22-JAN-14 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in PHILADELPHIA, PENNSYLVANIA
From 21-JAN-14 09:22:00 to 22-JAN-14 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in EASTERN MONTGOMERY, PENNSYLVANIA
From 21-JAN-14 08:00:00 to 22-JAN-14 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in LOWER BUCKS, PENNSYLVANIA
From 21-JAN-14 08:00:00 to 22-JAN-14 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in WESTERN CHESTER, PENNSYLVANIA
From 21-JAN-14 08:00:00 to 21-JAN-14 23:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in WESTERN MONTGOMERY, PENNSYLVANIA
From 21-JAN-14 07:00:00 to 21-JAN-14 23:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in UPPER BUCKS, PENNSYLVANIA
From 21-JAN-14 07:17:00 to 21-JAN-14 23:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Winter Weather in BERKS, PENNSYLVANIA
From 21-JAN-14 07:00:00 to 21-JAN-14 21:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in LEHIGH, PENNSYLVANIA
From 21-JAN-14 07:15:00 to 21-JAN-14 21:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 21-JAN-14 07:30:00 to 21-JAN-14 21:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Winter Weather in CARBON, PENNSYLVANIA
From 21-JAN-14 08:00:00 to 21-JAN-14 21:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Winter Weather in MONROE, PENNSYLVANIA
From 21-JAN-14 08:30:00 to 21-JAN-14 21:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Snow in EASTERN CHESTER, PENNSYLVANIA
From 21-JAN-14 08:00:00 to 22-JAN-14 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS