A low pressure system that traversed across the southern United States brought snow into southeastern Pennsylvania on the 17th. Snowfall in Philadelphia and its nearby suburbs averaged 1 to 4 inches. Little if any snow fell farther to the north in Pennsylvania. The snow fell during the morning commute and coupled with below freezing temperatures made for hazardous travel on untreated and less traveled roadways.
The snow spread into Southeastern Pennsylvania between Midnight EDT and 4 a.m. EDT on the 17th. Nearly as soon as it started in Philadelphia's far northwestern suburbs, it ended. However, in and around the local Philadelphia area the snow continued to fall into the first half of the afternoon on the 17th. It fell at its heaviest just before sunrise.
Representative snowfall included 4.7 inches at the Philadelphia International Airport, 4.3 inches in Brookhaven (Delaware), 3.3 inches in Nottingham (Chester County) and Lansdowne (Delaware County), 3.0 inches in Wynnewood (Montgomery County), 2.8 inches in Kennett Square (Chester County), 2.6 inches in Wayne (Delaware County), 2.4 inches in West Chester (Chester County), 2.3 inches in Exton (Chester County), 2.1 inches in Mount Airy (Philadelphia County), 2.0 inches in Marshallton (Chester County) and Fort Washington (Montgomery County), 1.8 inches in Ambler (Montgomery County), 1.2 inches in Langhorne (Bucks County) and Somerton (Philadelphia County) and 1.0 inch in Harleysville (Montgomery County).
The snow was caused by  a pair of low pressure systems that moved across the southern part of the United States.  On the morning the 16th the primary low pressure system was located over Arkansas. It moved east and at 8 p.m. EDT was located over northern Alabama. Very early on the 17th, a secondary low pressure system started forming near Wilmington, North Carolina as the primary low pressure system reached Atlanta, Georgia. While the secondary low pressure system moved offshore during the day on the 17th, the original (primary) low pressure system was slowly suppressed south as a high pressure system built into New York State. It was the combination of the southern storm track and dry air from this high pressure system that prevented the snow from spreading farther to the north in Pennsylvania.
March 17th marked the fourteenth and last time that an inch or more of snow fell in Philadelphia for the snowfall season on one calendar day. This tied for second place behind only the 1917-18 season which had seventeen calendar days of an inch or more of snow. The 2013-2014 seasonal total of 68.0 inches in Philadelphia was the second snowiest season on record, only surpassed by the 78.7 inches of snow that fell during the 2009-10 season. In Allentown, the seasonal total of 68.1 inches of snow was the third snowiest season on record and the snowiest since the second ranked 1995-6 season in which 71.4 inches of snow fell.  The snowiest season was 1993-4 in which 75.4 inches of snow fell.

Winter Weather in WESTERN CHESTER, PENNSYLVANIA
From 17-MAR-14 03:00:00 to 17-MAR-14 13:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in EASTERN CHESTER, PENNSYLVANIA
From 17-MAR-14 00:00:00 to 17-MAR-14 13:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in DELAWARE, PENNSYLVANIA
From 16-MAR-14 23:00:00 to 17-MAR-14 14:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in PHILADELPHIA, PENNSYLVANIA
From 16-MAR-14 23:30:00 to 17-MAR-14 14:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in LOWER BUCKS, PENNSYLVANIA
From 17-MAR-14 02:00:00 to 17-MAR-14 13:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter