Alert archive / Wyoming / Snow Squall Warnings in 2020

Snow Squall Warning 16, NWS Cheyenne, WY

February 12, 2020Laramie County, Wyoming

NWS Cheyenne, WY issued this snow squall warning at Feb 12, 2020, 2:41 PM MST for Laramie County, Wyoming. It was in force for 34 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Feb 12, 2020, 2:41 PM MST (21:41 UTC)
Expired: Feb 12, 2020, 3:15 PM MST
In force: 34 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 21:41 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, 9.7 hours before the alert went out and 202 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: 2241 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 127 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 snow squall warning 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 snow squall warning went out at Feb 12, 2:37 PM MST, 4 minutes earlier.

Area forecast discussion, Feb 12, 2:37 PM MST, 4 minutes before

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Hazardous weather outlook, Feb 12, 5:58 AM MST, 8 hours 43 minutes before

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In the hours before

Local storm report, Feb 12, 11:20 AM MST, 3 hours 21 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
Feb 12, 1:33 PM MST	Snow Squall Warning	CYS	Laramie	27 min
Feb 12, 1:36 PM MST	Winter Weather Advisory	CYS	Albany, Laramie	12 hr
Feb 12, 1:39 PM MST	High Wind Watch	CYS	Albany, Carbon, Laramie, Platte	23 hr
Feb 12, 2:15 PM MST	Snow Squall Warning	CYS	Laramie	30 min

Nearby

Snow Squall Warnings in Wyoming, 2020 Every snow squall warning in 2020

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.