Freezing rain at the onset of a protracted precipitation event resulted in hundreds of accidents, two that had fatalities, across Eastern Pennsylvania during the morning into the early afternoon of the 18th. There were also numerous pedestrian slip and fall accidents. A confluence of meteorological events made it easy for roadways and walkways to freeze quickly. Eventual rain on the 12th washed salt off of roadways. The 17th was a cold day with high temperatures barely, if at all, getting to the freezing mark. Skies started clear on the evening of the 17th and temperatures dropped quickly. The onset of precipitation on the morning of the 18th (from south to north freezing rain began between 630 a.m. EST and 10 a.m. EST) occurred rather quickly after skies became cloudy and temperatures had little time to rise. Temperatures were as low as the middle 20s when freezing rain began. The early morning arrival of freezing rain in most places also negated any indirect heating of paved surfaces by the sun.  Overall ice accumulations were less than two-tenths of an inch, but because icy conditions developed nearly instantaneously, driving and walking were extremely hazardous.  Warmer air at the surface moved in as the 18th progressed and the freezing rain changed to plain rain between 8 a.m. EST and 2 p.m. EST.  The freezing rain lasted the longest in the valleys of Berks County, the Lehigh Valley and the northern Philadelphia suburbs.
In Montgomery County, in Upper Merion Township, just after 7 a.m. EST, about sixty vehicles were involved in an accident on the westbound Schuylkill Expressway, Interstate 76, between exits 337 and 332. A 31-year-old man was fatally injured when he got out of his disabled vehicle and was struck by another vehicle. About thirty-one patients were transported to local hospitals for treatment of injuries. The accident closed the westbound lanes for eight hours. The eastbound lanes were also closed for emergency personnel to access the accident scene.  The Upper Merion Township building was opened as a warming shelter and the individuals who could not get off the roadway and were trapped were bussed to the facility.  In Delaware County, in Marple Township, on the Blue Route (Interstate 476) another multi-vehicle accident resulted in two fatalities and a major injury after a tractor-trailer jackknifed. Vehicles skidded into and underneath the tractor-trailer.  A 67-year-old and a 33-year-old man were killed at the scene. A third driver was hospitalized with head trauma.

The Pennsylvania Turnpike was closed in both directions from mile marker 302 to the Delaware River Bridge due to icy roadways.  This affected all interchanges and roadway in Berks, Chester, Montgomery and Philadelphia Counties.  The roadway was closed for six hours.   After the Turnpike reopened, a 45 mile per hour speed restriction was in place until road conditions improved. Sections of Interstate 95 in Philadelphia were also closed for several hours. All major bridges crossing the lower Delaware River in and around Philadelphia were closed for several hours:  The Commodore Barry, Walt Whitman, Ben Franklin, Betsy Ross and Tacony-Palmyra. Prior to the closing, there was a twenty-two vehicle accident on the Walt Whitman Bridge in South Philadelphia. Emergency dispatchers received hundreds of calls for ice-related crashes including one hundred in Bucks County and more than seventy-five in Montgomery County alone.  Flight delays were reported at the Philadelphia International Airport.
Representative ice accumulations included two-tenths of an inch in Graterford (Montgomery County), one-tenth of an inch in Gilbertsville (Montgomery County), Lionville (Chester County), Garnet Valley (Delaware County) and Alburtis (Lehigh County), five-hundredths of an inch in Reading (Berks County) and Doylestown (Bucks County) and a trace in Martins Creek (Northampton County) and Philadelphia.  Precipitation spread northward along the eastern seaboard from an inverted trough that extended northward from Georgia into the Delaware Valley. Because there was a broad south to southeast flow aloft preceding a cold front that was in the Ohio Valley on the morning of the 18th, warmer air at the surface was moved into the area and eroded and eliminated all sub-freezing temperatures as the day progressed.

Winter Weather in BERKS, PENNSYLVANIA
From 18-JAN-15 09:00:00 to 18-JAN-15 13:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in CARBON, PENNSYLVANIA
From 18-JAN-15 09:30:00 to 18-JAN-15 11:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Winter Weather in MONROE, PENNSYLVANIA
From 18-JAN-15 09:30:00 to 18-JAN-15 11:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Winter Weather in LEHIGH, PENNSYLVANIA
From 18-JAN-15 08:30:00 to 18-JAN-15 12:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 18-JAN-15 08:30:00 to 18-JAN-15 12:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in WESTERN CHESTER, PENNSYLVANIA
From 18-JAN-15 07:00:00 to 18-JAN-15 09:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Winter Weather in EASTERN CHESTER, PENNSYLVANIA
From 18-JAN-15 06:30:00 to 18-JAN-15 09:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Winter Weather in UPPER BUCKS, PENNSYLVANIA
From 18-JAN-15 07:00:00 to 18-JAN-15 13:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Winter Weather in WESTERN MONTGOMERY, PENNSYLVANIA
From 18-JAN-15 07:30:00 to 18-JAN-15 11:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LOWER BUCKS, PENNSYLVANIA
From 18-JAN-15 07:00:00 to 18-JAN-15 10:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Winter Weather in PHILADELPHIA, PENNSYLVANIA
From 18-JAN-15 06:30:00 to 18-JAN-15 09:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Winter Weather in DELAWARE, PENNSYLVANIA
From 18-JAN-15 06:30:00 to 18-JAN-15 09:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Winter Weather in EASTERN MONTGOMERY, PENNSYLVANIA
From 18-JAN-15 07:00:00 to 18-JAN-15 10:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper