Alert archive / Wyoming / Dense Fog Advisories in 2021

Dense Fog Advisory 8, NWS Cheyenne, WY

May 23, 2021Albany County, Laramie County, Wyoming

NWS Cheyenne, WY issued this dense fog advisory at May 23, 2021, 12:54 AM MDT for Albany County, Laramie County, Wyoming. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: May 23, 2021, 12:54 AM MDT (06:54 UTC)
Expired: May 23, 2021, 7:30 AM MDT
In force: 7 hr
Issued by: NWS Cheyenne, WY

Counties Albany County, WY, Laramie County, WY

The radar

The Cheyenne radar (KCYS), 50 km from the middle of the area, began a volume at 06:56 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 00:00Z, 6.9 hours before the alert went out and 245 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: 34 J/kg
Mixed-layer CIN: -91 J/kg
Mixed-layer LCL: 1134 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 279 m²/s²
0-3 km storm-relative helicity: 385 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

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 Cheyenne, WY wrote its last area forecast discussion before this dense fog advisory went out at May 22, 11:26 PM MDT, 1 hour 28 minutes earlier.

Area forecast discussion, May 22, 11:26 PM MDT, 1 hour 28 minutes before

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Hazardous weather outlook, May 22, 3:27 PM MDT, 9 hours 27 minutes before

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In the hours before

Local storm report, May 22, 9:15 PM MDT, 3 hours 39 minutes before

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The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 23, 2:04 AM MDT	High Wind Warning	CYS	Albany, Carbon	18 hr
May 23, 1:18 PM MDT	Special Weather Statement	CYS	Laramie	42 min
May 23, 1:28 PM MDT	Special Weather Statement	CYS	Platte	47 min
May 23, 1:35 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Platte	29 min
May 23, 1:59 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Niobrara, Platte	19 min
May 23, 2:03 PM MDT	Severe Thunderstorm Warning	CYS	Goshen, Laramie	42 min
May 23, 2:38 PM MDT	Severe Thunderstorm Warning	CYS	Goshen	24 min
May 23, 3:22 PM MDT	Areal Flood Advisory	CYS	Laramie	3 hr
May 23, 3:45 PM MDT	Special Weather Statement	CYS	Dawes	45 min
May 23, 3:53 PM MDT	Special Weather Statement	CYS	Morrill	52 min
May 23, 4:22 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	38 min
May 23, 4:31 PM MDT	Tornado Warning Considerable damage threat	CYS	Cheyenne	44 min

Nearby

Dense Fog Advisories in Wyoming, 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.