Utah, 2024

Dense Fog in Utah, December 30, 2024

December 30, 2024 · NWS GJT · 1 event in 1 county or zone

While drier air moving in to the region began to scour out the rich pockets of low level moisture across the lower elevation valleys of eastern Utah and western Colorado, deep moisture lingered in the eastern Uinta Basin. This moisture condensed during the overnight hours, creating dense fog.

Where it happened

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
1

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.

What happened

The episode as NWS GJT wrote it up.

While drier air moving in to the region began to scour out the rich pockets of low level moisture across the lower elevation valleys of eastern Utah and western Colorado, deep moisture lingered in the eastern Uinta Basin. This moisture condensed during the overnight hours, creating dense fog.

What forecasters said that day

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 30, 4:48 AM MST, 1 hour 57 minutes earlier.

Area forecast discussion, Dec 30, 4:48 AM MST, 1 hour 57 minutes before
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Hazardous weather outlook, Dec 30, 4:56 AM MST, 1 hour 49 minutes before
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    <section class="card" role="status" aria-live="polite">
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 dense fog. Local standard time, as filed.

Dense Fog, Eastern Uinta Basin

When
December 30, 6:45 AM MST to 10:15 AM MST
Where
Eastern Uinta Basin forecast zone
Reported by
ASOS
Coordinates
40.125, -109.518 (the zone’s center; the record gives no point)

At approximately 6:45AM local time, the KVEL ASOS at Vernal Airport, in Vernal, UT began reporting visibilities of 1/4 mile or less. Additionally, satellite imagery helped to confirm that the dense fog was more than just localized at the airport. As the sun rose, road cameras provided by the Utah Department of Transportation added visual conformation of the extent of the dense fog, particularly along the US Highway 40 corridor. This fog lingered into the morning before beginning to lift after 10AM local time, as dry air and sunshine began to erode the surface moisture. No reports of injuries, damages, or fatalities were received.

What these are

Dense Fog
Fog reducing visibility to a quarter mile or less, filed where it caused accidents or disruption.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Utah in 2024Every state in 2024This day in weather historyWarnings in Utah, December 2024

Sources

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 2026-09-24. Each event’s entry at NCEI: 1226704.