Colorado, 2017

Dense Fog in Colorado, February 13, 2017

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

Trapped low level moisture again resulted in areas of dense fog across some northwest and west-central Colorado valleys.

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
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  • Cold
  • Fire, smoke and dust
  • Marine and coastal
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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.

Trapped low level moisture again resulted in areas of dense fog across some northwest and west-central Colorado valleys.

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 Feb 12, 11:23 PM MST, 37 minutes earlier.

Area forecast discussion, Feb 12, 11:23 PM MST, 37 minutes before
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Hazardous weather outlook, Feb 12, 5:12 AM MST, 18 hours 48 minutes before
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In the hours before

Local storm report, Feb 12, 11:24 PM MST, 36 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, Upper Gunnison River Valley

When
February 13, 12:00 AM MST to 9:00 AM MST
Where
Upper Gunnison River Valley forecast zone
Reported by
AWOS
Coordinates
38.535, -107.650 (the zone’s center; the record gives no point)

Dense fog occurred across portions of the Upper Gunnison River Valley as visibilities dropped down to a quarter mile or less.

Dense Fog, Central Yampa River Basin

When
February 13, 7:00 AM MST to 1:00 PM MST
Where
Central Yampa River Basin forecast zone
Reported by
ASOS
Coordinates
40.361, -107.805 (the zone’s center; the record gives no point)

Dense fog occurred across much of the Central Yampa River Basin as visibilities dropped down to a quarter mile or less.

Dense Fog, Lower Yampa River Basin

When
February 13, 8:00 AM MST to 12:00 PM MST
Where
Lower Yampa River Basin forecast zone
Reported by
Department of Highways
Coordinates
40.066, -108.109 (the zone’s center; the record gives no point)

Dense fog occurred in portions of the Lower Yampa River Basin as visibilities dropped down 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, February 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 2026-09-24. Each event’s entry at NCEI: 685868, 685866, 685867.