Alert archive / Colorado / Dense Fog Advisories in 2021

Dense Fog Advisory 6, NWS Denver/Boulder, CO

May 29, 20214 counties in Colorado

NWS Denver/Boulder, CO issued this dense fog advisory at May 29, 2021, 6:20 AM MDT for 4 counties in Colorado. It was in force for 100 min.

The area

The counties it named.

The facts

Issued: May 29, 2021, 6:20 AM MDT (12:20 UTC)
Expired: May 29, 2021, 8:00 AM MDT
In force: 100 min
Issued by: NWS Denver/Boulder, CO

Counties Elbert County, CO, Lincoln County, CO, Washington County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 64 km from the middle of the area, began a volume at 12:19 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 0.3 hours before the alert went out and 53 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2325 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -78 m²/s²
0-3 km storm-relative helicity: 92 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this dense fog advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Denver/Boulder, CO wrote its last area forecast discussion before this dense fog advisory went out at May 29, 4:08 AM MDT, 2 hours 12 minutes earlier.

Area forecast discussion, May 29, 4:08 AM MDT, 2 hours 12 minutes before

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Hazardous weather outlook, May 29, 4:22 AM MDT, 1 hour 58 minutes before

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    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
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        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 29, 1:34 PM MDT	Special Weather Statement	BOU	Boulder	26 min
May 29, 1:55 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	35 min
May 29, 2:07 PM MDT	Severe Thunderstorm Warning	BOU	Douglas	23 min
May 29, 2:29 PM MDT	Severe Thunderstorm Warning	BOU	Weld	31 min
May 29, 2:59 PM MDT	Special Weather Statement	BOU	Weld	31 min
May 29, 3:39 PM MDT	Areal Flood Advisory	BOU	Larimer	83 min
May 29, 4:58 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	32 min
May 29, 5:16 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	29 min

Nearby

Dense Fog Advisories in Colorado, 2021 Every dense fog advisory in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.