A protracted event of light snow, sleet and especially freezing rain caused traveling difficulties and accidents in Eastern Pennsylvania from the evening of the 8th through the overnight on the 9th.  While precipitation amounts were not heavy and occurred intermittently, untreated roadways were treacherous. Ice accumulations averaged around one tenth of an inch and snow and sleet accumulations in the Lehigh Valley and Poconos averaged around one inch with lighter accumulations if any in the rest of Eastern Pennsylvania. Many schools on the 9th had delayed openings.
Across the Poconos, precipitation actually started as rain on the afternoon of the 8th. It changed to freezing rain on the evening of the 8th and to sleet overnight.  Precipitation changed to snow during the mid morning on the 9th and ended during the early morning on the 10th.  Across the Lehigh Valley, precipitation started as rain early on the 9th. It changed to freezing rain just before sunrise on the 9th with sleet occasionally mixing in. Precipitation changed to snow during the late afternoon on the 9th and ended during the early morning on the 10th.  Across Berks County and the northern Philadelphia suburbs, precipitation started as rain early on the 9th. It changed to freezing rain around sunrise on the 9th. Sleet mixed in with the freezing rain during the day on the 9th and the freezing rain changed to snow during the evening on the 9th and ended by the early morning on the 10th. Across the local Philadelphia area, freezing rain occurred during the morning and afternoon of the 9th (along with a little sleet) and spotty freezing drizzle occurred overnight on the 9th.
Representative ice accumulations included 0.20 inches in Huffs Church (Berks County) and Mount Pocono (Monroe County), 0.125 inches in Pennsbury Township (Chester County) and Canadensis (Monroe County), 0.10 inches in Perkasie (Bucks County), Allentown (Lehigh County) and Reading (Berks County), and around 0.05 inches at the Philadelphia International Airport, Pottstown (Montgomery County) and Doylestown (Bucks County).
Representative snow and sleet accumulations included 1.8 inches in Saylorsburg (Monroe County), 1.7 inches in Lehighton (Carbon County), 1.1 inches in Jim Thorpe (Carbon County) and Martins Creek (Northampton County), 1.0 inch in Mount Pocono (Monroe County), 0.6 inches in Hamburg (Berks County), 0.4 inches at the Lehigh Valley International Airport, 0.2 inches in Quakertown (Bucks County) and 0.1 inch in Reading (Berks County).
The wintry mix of precipitation was caused by the combination of waves of low pressure on a frontal boundary that supplied the moisture and precipitation and an arctic high pressure system to the north of the boundary that supplied the low level cold air. As this boundary sagged southward, the precipitation sagged southward with it.  At 7 a.m. EST on the 8th, the high pressure system was centered over James Bay and the frontal boundary across the Lehigh Valley. By 7 p.m. EST on the 8th, the frontal boundary moved southwest and cleared all of Eastern Pennsylvania with a wave of low pressure in northwest Pennsylvania. At 7 a.m. EST on the 9th, the frontal boundary was located over the Delmarva Peninsula with a wave of low pressure forming along it and a decaying low pressure system in central Pennsylvania. At 7 p.m. EST on the 9th, the frontal boundary was approaching Cape Hatteras, North Carolina and at 7 a.m. EST on the 10th dropped into northern Florida. By then, waves of low pressure were too far offshore to affect Pennsylvania.

Winter Weather in BERKS, PENNSYLVANIA
From 09-FEB-15 07:00:00 to 09-FEB-15 22:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in WESTERN CHESTER, PENNSYLVANIA
From 09-FEB-15 08:00:00 to 10-FEB-15 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in WESTERN MONTGOMERY, PENNSYLVANIA
From 09-FEB-15 03:00:00 to 10-FEB-15 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in UPPER BUCKS, PENNSYLVANIA
From 09-FEB-15 04:00:00 to 10-FEB-15 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LEHIGH, PENNSYLVANIA
From 09-FEB-15 05:00:00 to 10-FEB-15 02:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 09-FEB-15 05:00:00 to 10-FEB-15 02:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in MONROE, PENNSYLVANIA
From 08-FEB-15 22:00:00 to 10-FEB-15 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in CARBON, PENNSYLVANIA
From 08-FEB-15 22:00:00 to 10-FEB-15 01:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LOWER BUCKS, PENNSYLVANIA
From 09-FEB-15 05:00:00 to 10-FEB-15 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in EASTERN MONTGOMERY, PENNSYLVANIA
From 09-FEB-15 05:00:00 to 10-FEB-15 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in EASTERN CHESTER, PENNSYLVANIA
From 09-FEB-15 06:00:00 to 10-FEB-15 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in DELAWARE, PENNSYLVANIA
From 09-FEB-15 07:00:00 to 10-FEB-15 04:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in PHILADELPHIA, PENNSYLVANIA
From 09-FEB-15 05:00:00 to 10-FEB-15 03:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter