Cool, moist easterly flow underneath warm air advection aloft led to the formation of fog, some of which became locally dense.
Every event with a place to put it; 11 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.
Cool, moist easterly flow underneath warm air advection aloft led to the formation of fog, some of which became locally dense.
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 Dec 2, 5:43 AM EST, 22 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
11 dense fog. Local standard time, as filed.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
Observations from around the area indicate visibility fell to a quarter of a mile or less in dense fog.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Maryland in 2018Every state in 2018This day in weather historyWarnings in Maryland, December 2018
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: 795484, 795488, 795483, 795489, 795490, 795491, 795485, 795486, 795481, 795482, 795493.