A period of clearing during a winter storm event allowed low level moisture trapped in the Grand Valley of western Colorado to condense into dense fog during the morning hours.
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The episode as NWS GJT wrote it up.
A period of clearing during a winter storm event allowed low level moisture trapped in the Grand Valley of western Colorado to condense into dense fog during the morning hours.
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 Grand Junction, CO wrote its last area forecast discussion before the first event at Dec 2, 4:50 AM MST, 1 hour 10 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
1 dense fog. Local standard time, as filed.
Dense fog was observed within the Grand Valley, including at Grand Junction Regional Airport where visibility was reduced to less than a quarter of a mile.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2023Every state in 2023This day in weather historyWarnings in Colorado, December 2023
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: 1149262.