Closed low pressure slowly tracked into the Ohio Valley on the 31st before transferring its energy to low pressure off the Mid-Atlantic Coast on the 1st of February. The coastal low slowly tracked northeast while intensifying through midday on February the 2nd.
Snow overspread the area on the 31st of January ahead of the first low. Drier air and warmer air moved in aloft, causing snow to change to a light wintry mix on the night of the 31st into the 1st. However, another period of snow developed as the coastal low strengthened to the east later on the 1st and that continued into the 2nd.
Total snowfall accumulations ranged from around 1 to 3 inches in southern Maryland, to around 3 to 5 inches around Interstate 95, to around 6 to 12 inches west of Interstate 95, with locally 12 to 20 inches in the higher elevations of western Maryland as well as the Catoctin Mountains. Ice accumulation from freezing rain averaged around a tenth to a quarter inch east of the Catoctin Mountains.

Winter Weather in ST. MARY'S, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in CALVERT, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in PRINCE GEORGES, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in CHARLES, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in CENTRAL AND SOUTHEAST MONTGOMERY, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in CECIL, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in SOUTHEAST HARFORD, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in ANNE ARUNDEL, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in NORTHWEST MONTGOMERY, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in NORTHWEST HOWARD, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Weather in CENTRAL AND SOUTHEAST HOWARD, MARYLAND
From 31-JAN-21 00:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.

Winter Storm in EXTREME WESTERN ALLEGANY, MARYLAND
From 31-JAN-21 04:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

The snow continued at times into February 2nd.

Winter Storm in GARRETT, MARYLAND
From 31-JAN-21 04:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

The snow continued at times into February 2nd.

Winter Storm in WASHINGTON, MARYLAND
From 31-JAN-21 04:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

The snow continued at times into February 2nd.

Winter Storm in CENTRAL AND EASTERN ALLEGANY, MARYLAND
From 31-JAN-21 04:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

The snow continued at times into February 2nd.

Winter Storm in SOUTHERN BALTIMORE, MARYLAND
From 31-JAN-21 04:00:00 to 31-JAN-21 23:59:00 (EST-5)
Reported by: Trained Spotter

Wintry precipitation continued at times into February 2nd.