Alert archive / Wyoming / Snow Squall Warnings in 2021

Snow Squall Warning 3, NWS Riverton, WY

December 26, 2021Sweetwater County, Wyoming

NWS Riverton, WY issued this snow squall warning at Dec 26, 2021, 10:12 AM MST for Sweetwater County, Wyoming. It was in force for 48 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Dec 26, 2021, 10:12 AM MST (17:12 UTC)
Expired: Dec 26, 2021, 11:00 AM MST
In force: 48 min
Issued by: NWS Riverton, WY
Area: Storm-based polygon

County Sweetwater County, WY

The radar

The Riverton/Lander radar (KRIW), 153 km from the middle of the area, began a volume at 17:14 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.

What was reported inside it

Time	Report	Where	Remark
Dec 26, 10:30 AM MST	NON-TSTM WND GST 63	8 Se Reliance, WY	ASOS STATION KRKS ROCK SPRINGS AIRPORT.
Dec 26, 10:44 AM MST	NON-TSTM WND GST 59	16 Se Rock Springs, WY	MESONET STATION SNOW4 ROCK SPRINGS 15 SE.
Dec 26, 10:46 AM MST	NON-TSTM WND GST 60	6 Se Superior, WY	MESONET STATION WY11 SUPERIOR 6 SE (WYDOT).

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Riverton, WY (KRIW), launched 12:00Z, 5.2 hours before the alert went out and 156 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: 1333 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 188 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

120 
WWUS55 KRIW 261712
SQWRIW

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Snow Squall Warning
National Weather Service Riverton WY
1012 AM MST Sun Dec 26 2021

WYC037-261800-
/O.NEW.KRIW.SQ.W.0003.211226T1712Z-211226T1800Z/
Sweetwater-
1012 AM MST Sun Dec 26 2021

The National Weather Service in Riverton has issued a

* Snow Squall Warning for...
  Western Sweetwater County in south central Wyoming...

* Until 1100 AM MST.

* At 1010 AM MST, a dangerous snow squall was located along a line 
  extending from Killpecker Dune Field to near Flaming Gorge, moving 
  east at 45 mph.

  HAZARD...Heavy snow and blowing snow. Wind gusts greater than 40 
           mph. Frequent gusts of 40 to 50 mph have been recorded 
           along I-80 during the past hour.

  SOURCE...Radar and webcams.

  IMPACT...Dangerous life-threatening travel.

* This includes Interstate 80 between mile markers 68 and 150.
 
Locations impacted include...
Rock Springs, Green River, Superior, Little America, Killpecker Dune 
Field, Reliance, Point Of Rocks, and Flaming Gorge National 
Recreation Area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Consider avoiding or delaying travel until the snow squall passes
your location. If you must travel, use extra caution and allow extra
time. Rapid changes in visibility and slick road conditions may lead
to accidents.

&&

LAT...LON 4194 10981 4226 10849 4226 10823 4124 10852
      4105 10997
TIME...MOT...LOC 1710Z 253DEG 48KT 4199 10923 4118 10945 

$$

Straub

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 26, 7:43 AM MST	Special Weather Statement	RIW	Teton	62 min
Dec 26, 8:35 AM MST	Special Weather Statement	RIW	Lincoln, Park, Sublette	55 min
Dec 26, 9:31 AM MST	Snow Squall Warning	RIW	Sweetwater	44 min
Dec 26, 9:37 AM MST	Special Weather Statement	RIW	Fremont, Hot Springs	53 min
Dec 26, 10:28 AM MST	Special Weather Statement	RIW	Big Horn, Fremont, Hot Springs	62 min
Dec 26, 11:00 AM MST	Snow Squall Warning	RIW	Sweetwater	45 min
Dec 26, 11:26 AM MST	Special Weather Statement	RIW	Fremont, Natrona	64 min
Dec 26, 11:38 AM MST	Snow Squall Warning	RIW	Sweetwater	52 min
Dec 26, 1:51 PM MST	Special Weather Statement	RIW	Lincoln	54 min
Dec 26, 2:45 PM MST	Special Weather Statement	RIW	Lincoln, Sublette, Teton	60 min
Dec 26, 3:44 PM MST	Special Weather Statement	RIW	Sublette	46 min

Nearby

Snow Squall Warnings in Wyoming, 2021 Every snow squall warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.