Colorado, 2017

Dense Fog in Colorado, January 13, 2017

January 13, 2017 · NWS GJT · 3 events in 3 counties and zones

An abundance of low-level moisture over snow-covered valley floors resulted in the formation of dense fog in portions of the Grand Valley and up the Colorado River Valley to the Silt area.

Where it happened

Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
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  • Floods
  • Wind
  • Hail
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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
3

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.

An abundance of low-level moisture over snow-covered valley floors resulted in the formation of dense fog in portions of the Grand Valley and up the Colorado River Valley to the Silt area.

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 Jan 13, 1:32 AM MST, 1 hour 28 minutes earlier.

Area forecast discussion, Jan 13, 1:32 AM MST, 1 hour 28 minutes before
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In the hours before

Local storm report, Jan 12, 9:33 PM MST, 5 hours 27 minutes before
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Local storm report, Jan 12, 9:34 PM MST, 5 hours 26 minutes before
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Local storm report, Jan 12, 9:35 PM MST, 5 hours 25 minutes before
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Local storm report, Jan 12, 10:26 PM MST, 4 hours 34 minutes before
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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

3 dense fog. Local standard time, as filed.

Dense Fog, Debeque to Silt Corridor

When
January 13, 3:00 AM MST to 6:00 AM MST
Where
Debeque to Silt Corridor forecast zone
Reported by
ASOS
Coordinates
39.308, -108.185 (the zone’s center; the record gives no point)

Dense fog occurred in some locations as visibilities dropped down to a quarter mile or less.

Dense Fog, Grand Valley

When
January 13, 6:00 AM MST to 9:00 AM MST
Where
Grand Valley forecast zone
Reported by
NWS Employee
Coordinates
39.308, -108.185 (the zone’s center; the record gives no point)

Dense fog occurred across portions of the Grand Valley, mainly west of 25 Road, as visibilities dropped to a quarter mile or less.

Dense Fog, Upper Yampa River Basin

When
January 13, 7:00 PM MST to 11:30 PM MST
Where
Upper Yampa River Basin forecast zone
Reported by
AWOS
Coordinates
40.485, -106.991 (the zone’s center; the record gives no point)

Dense fog occurred across portions of the upper Yampa River Basin as visibilities dropped to a quarter mile or less.

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 Colorado in 2017Every state in 2017This day in weather historyWarnings in Colorado, January 2017

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 2026-10-01. Each event’s entry at NCEI: 683267, 683268, 704781.