Warm and moist air continued to overrun surface cold air and a light snowpack, causing areas of dense fog to develop during the early morning hours of the 24th.
Every event with a place to put it; 4 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.
Warm and moist air continued to overrun surface cold air and a light snowpack, causing areas of dense fog to develop during the early morning hours of the 24th.
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, 9:11 PM EST, 2 hours 38 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
6 dense fog. Local standard time, as filed.
Visibility was estimated to be around one quarter mile across portions of northern Baltimore County.
Visibility was reported to be around one quarter mile at Westminster.
Visibility was estimated to be around one quarter mile across portions of central and eastern Allegany County.
Visibility was reported to be around one quarter mile at Hagerstown.
Visibility was estimated to be around one quarter mile across the county.
Visibility was reported to be around one quarter mile at Gaithersburg.
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: 362233, 362235, 362232, 362237, 362234, 362238.