An intense low pressure system brought a winter storm to the Poconos and a wintry mix at the start of the precipitation event across most of the rest of Eastern Pennsylvania. A combination of snow, sleet and freezing rain occurred throughout the event in the Poconos, but precipitation changed to rain elsewhere in Eastern Pennsylvania. Snowfall averaged 1 to 3 inches, except 3 to 6 inches in the Poconos. Little if any snow fell in the local Philadelphia area. Ice accumulations averaged one tenth to one quarter of an inch, highest in the Lehigh Valley. The wintry mix of precipitation made for hazardous traveling conditions.  The wintry weather also caused some delays and cancellations at the Lehigh Valley International Airport.

Snow began throughout most of Eastern Pennsylvania (was mixed precipitation in Philadelphia) on the afternoon of the 26th. The snow fell at its heaviest during the mid to late afternoon. As warmer air moved in aloft, the snow changed to sleet and freezing rain in the Philadelphia northwest suburbs during the middle of the afternoon, in the Lehigh Valley and Berks County during the late afternoon and took most of the evening for this to occur in the Poconos. Meanwhile the local Philadelphia area changed to plain rain quickly. In the Philadelphia northwest suburbs and Berks County, the sleet and freezing rain changed to plain rain during the late afternoon. This change in the Lehigh Valley did not occur until the evening of the 26th. In the Poconos, a wintry mix persisted until the precipitation ended on the morning of the 27th.
Representative snowfall included 6.3 inches in Tobyhanna (Monroe County), 5.5 inches in Pocono Summit (Monroe County), 4.5 inches in Lake Harmony and Albrightsville (Carbon County), 3.3 inches in Bangor (Northampton County), 2.5 inches in Palmerton (Carbon County) and East Stroudsburg (Monroe County), 2.1 inches in Martins Creek (Northampton County), 2.0 inches in Schnecksville (Lehigh County) and Upper Frederick Township (Montgomery County), 1.3 inches at the Lehigh Valley International Airport, 1.1 inches in Quakertown (Bucks County) and 1.0 inch in Honey Brook (Chester County), West Chester (Chester County) and Fleetwood (Berks County).
The wintry weather was caused by a low pressure system that moved from Texas on Christmas Day northeast into the Tennessee Valley on the 26th. A secondary low pressure system formed in the Carolinas on the 26th and became the main low. This low moved northeast and passed through southern Delaware on the evening of the 26th and across southeast New Jersey overnight on the 26th. The low pressure system reached the eastern tip of Long Island, New York late in the morning on the 27th. That storm track made it difficult for warm air at the surface to reach into the Poconos and slowed its progression inland elsewhere.

Winter Storm in CARBON, PENNSYLVANIA
From 26-DEC-12 13:00:00 to 27-DEC-12 11:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in MONROE, PENNSYLVANIA
From 26-DEC-12 13:00:00 to 27-DEC-12 11:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in BERKS, PENNSYLVANIA
From 26-DEC-12 12:00:00 to 26-DEC-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LEHIGH, PENNSYLVANIA
From 26-DEC-12 12:30:00 to 26-DEC-12 23:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 26-DEC-12 13:00:00 to 27-DEC-12 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in EASTERN CHESTER, PENNSYLVANIA
From 26-DEC-12 12:00:00 to 26-DEC-12 16:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in EASTERN MONTGOMERY, PENNSYLVANIA
From 26-DEC-12 12:30:00 to 26-DEC-12 16:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LOWER BUCKS, PENNSYLVANIA
From 26-DEC-12 13:00:00 to 26-DEC-12 16:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in WESTERN CHESTER, PENNSYLVANIA
From 26-DEC-12 12:00:00 to 26-DEC-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in WESTERN MONTGOMERY, PENNSYLVANIA
From 26-DEC-12 12:30:00 to 26-DEC-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in UPPER BUCKS, PENNSYLVANIA
From 26-DEC-12 13:00:00 to 26-DEC-12 18:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter