Low pressure tracked through the central portion of the country while surface high pressure remained off the New England Coast. Warm and moist air overran surface cold air while a light snowpack remained on the ground.
Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LWX wrote it up.
Low pressure tracked through the central portion of the country while surface high pressure remained off the New England Coast. Warm and moist air overran surface cold air while a light snowpack remained on the ground. The warm and moist air interacted with the surface cold air and snowpack, causing areas of dense fog to develop.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Baltimore/Washington wrote its last area forecast discussion before the first event at Jan 23, 3:49 AM EST, 0 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
8 dense fog. Local standard time, as filed.
Visibility was estimated to be around one quarter mile across the northern portion of the county.
Visibility was reported to be around one quarter mile at Westminster.
Visibility was estimated to be around one quarter mile across the county.
Visibility was reported to be around one quarter mile at Gaithersburg.
Visibility was reported to be around one quarter mile at Frederick.
Visibility was reported to be around one quarter mile at Hagerstown.
Visibility was reported to be around one quarter mile at Andrews Air Force Base.
Visibility was reported to be around one quarter mile at BWI Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2012Every state in 2012This day in weather historyWarnings in Maryland, January 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 362221, 362228, 362222, 362223, 362226, 362225, 362230, 362229.