Low pressure tracked through the Great Lakes on January 18. Warm advection driven precipitation overspread the mid-Atlantic throughout the day ahead of a warm front. The antecedent air mass was colder than average, allowing precipitation to fall as a mix of snow, sleet, and freezing rain for a considerable time over parts of the region, despite the area of low pressure tracking so far west and gradually drawing warmer air into the region. Precipitation eventually changed over to mainly rain.

Winter Weather in BERKS, PENNSYLVANIA
From 18-JAN-20 09:00:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A light mix of snow and freezing rain occurred. Snowfall amounts ranged from 1 to 2 inches, and the Reading, PA ASOS (KRDG) measured 0.06 inches of ice accretion.

Winter Weather in UPPER BUCKS, PENNSYLVANIA
From 18-JAN-20 10:00:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Light snow occurred. A report of 2.8 inches of snow was received from East Rockhill Twp.

Winter Weather in LOWER BUCKS, PENNSYLVANIA
From 18-JAN-20 10:00:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A light mix of snow and freezing rain occurred. Near Doylestown, 1.6 inches of snow was measured, and the Doylestown ASOS (KDYL) measured 0.16 inches of ice accretion.

Winter Weather in LEHIGH, PENNSYLVANIA
From 18-JAN-20 10:00:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A mix of snow and freezing rain occurred. A trained spotter in Washington Twp reported 3.9 inches of snow. Trace amounts of icing were also observed.

Winter Weather in EASTERN CHESTER, PENNSYLVANIA
From 18-JAN-20 15:45:00 to 18-JAN-20 19:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A light mix of snow and freezing rain occurred. Several snow reports of around one inch were received. A trained spotter in West Chester measured 0.10 inches of ice accretion.

Winter Weather in MONROE, PENNSYLVANIA
From 18-JAN-20 11:00:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A light mix of snow and freezing rain occurred. A trained spotter in Tobyhanna measured 3.0 inches of snow. The Mount Pocono, PA ASOS (KMPO) measured 0.04 inches of ice accretion.

Winter Weather in WESTERN MONTGOMERY, PENNSYLVANIA
From 18-JAN-20 09:30:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A light mix of snow and freezing rain occurred. A report of 2.6 inches of snow was reported near Skippack. The Pottstown, PA ASOS (KPTW) measured 0.18 inches of ice accretion.

Winter Weather in EASTERN MONTGOMERY, PENNSYLVANIA
From 18-JAN-20 15:45:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A light mix of snow and freezing rain occurred. A report of 1.1 inches of snow was received from Plymouth Meeting. In addition, numerous surrounding observations indicate that light freezing rain occurred in this zone.

Winter Weather in PHILADELPHIA, PENNSYLVANIA
From 18-JAN-20 15:45:00 to 18-JAN-20 19:45:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A light mix of snow and freezing rain occurred. Snowfall totals were near to below one inch. The Philadelphia International Airport ASOS (KPHL) measured 0.10 inches of ice accretion.

Winter Weather in CARBON, PENNSYLVANIA
From 18-JAN-20 10:30:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Light snow occurred. A report of 2.1 inches of snow was received in Lehighton. Surrounding reports indicate that some slightly higher totals may have occurred, and that light icing may have also occurred.

Winter Weather in DELAWARE, PENNSYLVANIA
From 18-JAN-20 15:45:00 to 18-JAN-20 19:45:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A light mix of snow and freezing rain occurred. Several reports of around one inch of snow were received. A trained spotter in Thornton measured 0.10 inches of ice accretion.

Winter Weather in NORTHAMPTON, PENNSYLVANIA
From 18-JAN-20 10:30:00 to 18-JAN-20 20:30:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Light snow occurred, with a report of up to 3.5 inches of snow received from Nazareth and numerous other 2 to 3 inch reports. Reports from surrounding areas suggest some light freezing rain may have also occurred.

Winter Weather in WESTERN CHESTER, PENNSYLVANIA
From 18-JAN-20 09:00:00 to 18-JAN-20 19:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

A light mix of snow and freezing rain occurred. In East Nantmeal Twp, a report was received of 2.0 inches of snow and 0.05 inches of ice accretion.