High pressure was centered off the Atlantic coast.  Southerly flow has transported mild temperatures and moisture northward into the Mid Atlantic Region.  Calm winds and low level moisture led to dense fog overnight.  This was the second consecutive day of dense fog in the region.

Dense Fog in MONTGOMERY, MARYLAND
From 13-JAN-13 03:35:00 to 13-JAN-13 10:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at Gaithersburg Airport.

Dense Fog in HOWARD, MARYLAND
From 13-JAN-13 03:35:00 to 13-JAN-13 10:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at Gaithersburg Airport.

Dense Fog in SOUTHERN BALTIMORE, MARYLAND
From 13-JAN-13 04:00:00 to 13-JAN-13 18:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Martins State Airport.

Dense Fog in NORTHERN BALTIMORE, MARYLAND
From 12-JAN-13 22:00:00 to 13-JAN-13 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at York Airport.

Dense Fog in CARROLL, MARYLAND
From 12-JAN-13 22:00:00 to 13-JAN-13 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at York Airport.

Dense Fog in ANNE ARUNDEL, MARYLAND
From 13-JAN-13 02:30:00 to 13-JAN-13 12:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Baltimore Washington Airport.

Dense Fog in PRINCE GEORGES, MARYLAND
From 13-JAN-13 02:30:00 to 13-JAN-13 12:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Baltimore Washington Airport.

Dense Fog in ST. MARY'S, MARYLAND
From 12-JAN-13 21:00:00 to 13-JAN-13 09:55:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at St Mary's Airport and Patuxent Air Force Base.

Dense Fog in CALVERT, MARYLAND
From 12-JAN-13 21:00:00 to 13-JAN-13 09:55:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at St Mary's Airport and Patuxent Air Force Base.

Dense Fog in CHARLES, MARYLAND
From 12-JAN-13 21:00:00 to 13-JAN-13 09:55:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Visibility was reported around a quarter mile at St Mary's Airport and Patuxent Air Force Base.

Dense Fog in HARFORD, MARYLAND
From 13-JAN-13 04:00:00 to 13-JAN-13 18:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Martins State Airport.

Dense Fog in FREDERICK, MARYLAND
From 12-JAN-13 17:49:00 to 14-JAN-13 00:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Dulles International and Leesburg Airports.

Dense Fog in WASHINGTON, MARYLAND
From 13-JAN-13 03:14:00 to 13-JAN-13 08:15:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Hagerstown Airport.

Dense Fog in CENTRAL AND EASTERN ALLEGANY, MARYLAND
From 13-JAN-13 07:11:00 to 13-JAN-13 11:47:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Visibility was reported around a quarter mile at Cumberland Airport.