Alert archive / Wyoming / Winter Storm Watches in 2021

Winter Storm Watch 13, NWS Cheyenne, WY

December 22, 2021Albany County, Carbon County, Wyoming

NWS Cheyenne, WY issued this winter storm watch at Dec 22, 2021, 2:36 AM MST for Albany County, Carbon County, Wyoming. It took effect at Dec 23, 2021, 3:00 PM MST. It was in force for .

The area

The counties it named.

The facts

Issued
Dec 22, 2021, 2:36 AM MST (09:36 UTC)
In effect from
Dec 23, 2021, 3:00 PM MST
Expired
Dec 22, 2021, 1:55 PM MST
In force
Issued by
NWS Cheyenne, WY

Counties Albany County, WY, Carbon County, WY

The radar

The Cheyenne radar (KCYS), 140 km from the middle of the area, began a volume at 09:38 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

Riverton, WY (KRIW), launched 00:00Z, 9.6 hours before the alert went out and 230 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-pSkew-T log-p diagram, Riverton, WY at 00:00Z on 2021-12-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Riverton, WY at 00:00Z on 2021-12-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 107 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
2779 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
107 m²/s²
0-3 km storm-relative helicity
199 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

682 
WWUS45 KCYS 220936
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
236 AM MST Wed Dec 22 2021

...HEAVY SNOW EXPECTED FOR THE MOUNTAINS THURSDAY THROUGH EARLY
THIS WEEKEND...

WYZ112-114-222315-
/O.NEW.KCYS.WS.A.0013.211223T2200Z-211225T1800Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
236 AM MST Wed Dec 22 2021

...WINTER STORM WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH
SATURDAY MORNING...

* WHAT...Heavy snow and blowing snow likely. Total snow 
  accumulations of 1 to 3 feet possible late Thursday afternoon 
  through Saturday morning. Winds could gust as high as 60 mph.

* WHERE...The Sierra Madre Range and the Snowy Range.

* WHEN...From Thursday afternoon through Saturday morning.

* IMPACTS...Travel could be very difficult to impossible. Blowing
  snow could significantly reduce visibility and drifting snow. 

* ADDITIONAL DETAILS...Strong gusty winds may result in
  significant blowing snow and also very cold wind chill
  temperatures below zero by Friday night. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

TT
1 follow-up statement
966 
WWUS45 KCYS 222055
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
155 PM MST Wed Dec 22 2021

...HEAVY SNOW EXPECTED FOR THE MOUNTAINS THURSDAY THROUGH EARLY
THIS WEEKEND...

WYZ112-114-231200-
/O.UPG.KCYS.WS.A.0013.211223T2200Z-211225T1800Z/
/O.NEW.KCYS.WS.W.0019.211223T2200Z-211225T1800Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
155 PM MST Wed Dec 22 2021

...WINTER STORM WARNING IN EFFECT FROM 3 PM THURSDAY TO 11 AM MST
SATURDAY...

* WHAT...Heavy snow expected. Total snow accumulations of up to 3
  feet for the Sierra Madre Range and 2 feet for the Snowy Range.  
  Winds gusting as high as 55 mph.

* WHERE...Sierra Madre Range and Snowy Range in southeast Wyoming.

* WHEN...From 3 PM Thursday to 11 AM MST Saturday.

* IMPACTS...Travel could be very difficult to impossible. Patchy
  blowing snow could significantly reduce visibility. The
  hazardous conditions could impact the morning or evening
  commute. Hikers and snow mobilers likely to become disoriented
  and lost with very poor visibility in heavy snow and blowing
  snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency. 

The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

&&

$$

WYZ111-113-231200-
/O.NEW.KCYS.WS.A.0014.211224T0000Z-211224T1800Z/
Southwest Carbon County-Upper North Platte River Basin-
Including the cities of Baggs, Saratoga, and Encampment
155 PM MST Wed Dec 22 2021

...WINTER STORM WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY MORNING...

* WHAT...Heavy snow possible. Total snow accumulations of 6 to 8 
  inches possible. Winds could gust as high as 50 mph.

* WHERE...Southwest Carbon County to include Dixon...Baggs and
  Dad. Upper North Platte River Valley to include Saratoga and
  Encampment.

* WHEN...From Thursday afternoon through Friday morning.

* IMPACTS...Travel could be very difficult. The hazardous
  conditions could impact the morning or evening commute. Strong
  winds could cause very poor visibility in blowing snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts for updates on this situation. 

&&

$$

WYZ109-110-231200-
/O.NEW.KCYS.WS.A.0014.211224T0000Z-211225T0000Z/
Central Carbon County-North Snowy Range Foothills-
Including the cities of Rawlins, Arlington, and Elk Mountain
155 PM MST Wed Dec 22 2021

...WINTER STORM WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY AFTERNOON...

* WHAT...Blizzard conditions possible. Total snow accumulations of
  5 to 8 inches possible. Winds could gust as high as 70 mph.

* WHERE...Central Carbon County to include Rawlins and Sinclair.
  North Snowy Range Foothills to include Arlington and Elk 
  Mountain.

* WHEN...From Thursday afternoon through Friday afternoon.

* IMPACTS...Travel could be very difficult. Areas of blowing snow
  could significantly reduce visibility. The hazardous conditions
  could impact the morning or evening commute. Near zero
  visibility in snow and blowing snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare for possible blizzard conditions. Continue to monitor the
latest forecasts for updates on this situation. 

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 21, 8:42 PM MSTHigh Wind WarningCYSLaramie8 hr
Dec 22, 3:43 AM MSTHigh Wind WatchCYSAlbany, Carbon, Converse, Laramie, Platte26 hr
Dec 22, 1:01 PM MSTHigh Wind WarningCYSAlbany, Laramie, Platte37 hr
Dec 22, 1:55 PM MSTWinter Storm WatchCYSAlbany, Carbon16 hr
Dec 22, 1:55 PM MSTWinter Storm WarningCYSAlbany, Carbon69 hr

Nearby

Winter Storm Watches in Wyoming, 2021Every winter storm watch 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.