Alert archive / Wyoming / Winter Storm Warnings in 2021

Winter Storm Warning 1, NWS Cheyenne, WY

January 4, 2021Albany County, Carbon County, Wyoming

NWS Cheyenne, WY issued this winter storm warning at Jan 4, 2021, 1:09 PM MST for Albany County, Carbon County, Wyoming. It took effect at Jan 4, 2021, 11:00 PM MST. It was in force for 18 hr. 13 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jan 4, 2021, 1:09 PM MST (20:09 UTC)
In effect from
Jan 4, 2021, 11:00 PM MST
Expired
Jan 5, 2021, 5:00 PM MST
In force
18 hr
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 20:06 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

TimeReportWhereRemark
Jan 5, 5:00 PM MSTSNOW 614 Nne Skyline, WYSOUTH BRUSH CREEK SNOTEL IN THE SNOWY RANGE. ELEVATION 8440 FEET. SNOW WATER EQUIVALENT IS 0.6 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 67 Wsw Centennial, WYCINNABAR PARK SNOTEL IN THE SNOWY RANGE. ELEVATION 9574 FEET. SNOW WATER EQUIVALENT IS 0.5 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 7.57 Wnw Centennial, WYBROOKLYN LAKE SNOTEL IN THE SNOWY RANGE. ELEVATION 10240 FEET. SNOW WATER EQUIVALENT IS 0.5 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 7.58 Sw Skyline, WYBLACKHALL MOUNTAIN SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 9820 FEET. SNOW WATER EQUIVALENT IS 0.5 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 910 Ssw Arlington, WYSAND LAKE SNOTEL IN THE SNOWY RANGE. ELEVATION 10050 FEET. SNOW WATER EQUIVALENT IS 0.6 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 914 E Dixon, WYBATTLE MOUNTAIN SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 7440 FEET. SNOW WATER EQUIVALENT IS 0.9 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTSNOW 9.68 Wsw Encampment, WYWEBBER SPRINGS SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 9250 FEET. SNOW WATER EQUIVALENT IS 0.8 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 13.212 Sw Encampment, WYLITTLE SNAKE RIVER SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 8915 FEET. SNOW WATER EQUIVALENT IS 1.1 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 13.215 Ssw Encampment, WYWHISKEY PARK SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 8950 FEET. SNOW WATER EQUIVALENT IS 1.1 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 15.620 Wnw Encampment, WYDIVIDE PEAK SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 8880 FEET. SNOW WATER EQUIVALENT IS 1.3 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 16.514 Wnw Centennial, WYMED BOW SNOTEL IN THE SNOWY RANGE. ELEVATION 10510 FEET. SNOW WATER EQUIVALENT IS 1.1 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 1810 Wsw Encampment, WYOLD BATTLE SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 10000 FEET. SNOW WATER EQUIVALENT IS 1.2 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.
Jan 5, 5:00 PM MSTHEAVY SNOW 19.514 W Centennial, WYNORTH FRENCH CREEK SNOTEL IN THE SNOWY RANGE. ELEVATION 10130 FEET. SNOW WATER EQUIVALENT IS 1.3 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS OVER PAST 18 HOURS.

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, 8.2 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 12:00Z on 2021-01-04Temperature 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 12:00Z on 2021-01-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.1939587897117Sfc1 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
2379 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
251 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

972 
WWUS45 KCYS 042009
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
109 PM MST Mon Jan 4 2021

...MODERATE TO HEAVY MOUNTAIN SNOW EXPECTED LATE TONIGHT THROUGH
TUESDAY...

WYZ112-114-051200-
/O.UPG.KCYS.WW.Y.0001.210105T0600Z-210106T0000Z/
/O.NEW.KCYS.WS.W.0001.210105T0600Z-210106T0000Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
109 PM MST Mon Jan 4 2021

...WINTER STORM WARNING IN EFFECT FROM 11 PM THIS EVENING TO 5 PM
MST TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 12 to 16
  inches. Winds gusting as high as 55 mph producing blowing snow
  and near zero visibilities at times.

* WHERE...Snowy and Sierra Madre Ranges.

* WHEN...11 PM this evening to 5 PM Tuesday.

* IMPACTS...Dangerous mountain travel due to icy, snow packed
  roads and low visibilities in falling and blowing snow. Outdoor
  recreation could be life threatening to those caught unprepared
  for severe winter conditions.

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.

&&

$$

Rubin
3 follow-up statements
805 
WWUS45 KCYS 050254
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
754 PM MST Mon Jan 4 2021

...MODERATE TO HEAVY MOUNTAIN SNOW EXPECTED LATE TONIGHT THROUGH
TUESDAY...
...AREAS OF BLOWING SNOW AND REDUCED VISIBILITIES ALONG THE I-80
CORRIDOR ARLINGTON TO ELK MOUNTAIN BEGINNING AROUND SUNRISE 
THROUGH SUNDOWN TUESDAY...

WYZ112-114-060000-
/O.CON.KCYS.WS.W.0001.210105T0600Z-210106T0000Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
754 PM MST Mon Jan 4 2021

...WINTER STORM WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING
TO 5 PM MST TUESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 12 to 
  16 inches. Winds gusting as high as 55 mph producing blowing 
  snow and near zero visibilities at times.

* WHERE...Snowy and Sierra Madre Ranges.

* WHEN...11 PM this evening to 5 PM Tuesday.

* IMPACTS...Dangerous mountain travel due to icy, snow packed 
  roads and low visibilities in falling and blowing snow. 
  Outdoor recreation could be life threatening to those caught 
  unprepared for severe winter conditions.

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.

&&

$$

WYZ110-060000-
/O.NEW.KCYS.WW.Y.0002.210105T1200Z-210106T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
754 PM MST Mon Jan 4 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 5 AM TO 5 PM MST
TUESDAY...

* WHAT...Snow expected. Total snow accumulations of up to 3
  inches. Winds gusting as high as 65 mph.

* WHERE...Arlington and Elk Mountain along Interstate 80 between
  Laramie and Rawlins. 

* WHEN...From 5 AM to 5 PM MST Tuesday.

* IMPACTS...Plan on slippery road conditions. Widespread blowing
  snow could significantly reduce visibility, even producing
  whiteout conditions at times. The hazardous conditions could 
  impact the morning or evening commute. 


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$

AB
263 
WWUS45 KCYS 051119
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
419 AM MST Tue Jan 5 2021

...WINTER CONDITIONS IMPACTING AREAS WEST OF THE LARAMIE RANGE
TODAY... 

WYZ112-114-060000-
/O.CON.KCYS.WS.W.0001.000000T0000Z-210106T0000Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
419 AM MST Tue Jan 5 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Heavy mountain snow expected. Total snow accumulations of
  8 to 12 inches, with locally higher amounts possible. Winds
  gusting up to 55 MPH resulting in blowing snow and near blizzard
  conditions. 

* WHERE...Snowy and Sierra Madre mountain ranges.

* WHEN...Until 5 PM MST today. 

* IMPACTS...Extremely dangerous or impossible mountain travel due
  to icy, snow packed roads and near zero visibilities in falling
  and blowing snow. Outdoor recreation will be life threatening to
  those caught unprepared for severe winter conditions. 

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.

&&

$$

WYZ104-105-109-111-113-060000-
/O.EXA.KCYS.WW.Y.0002.210105T1200Z-210106T0000Z/
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Carbon County-Southwest Carbon County-
Upper North Platte River Basin-
Including the cities of Seminoe Dam, Medicine Bow, Shirley Basin,
Rawlins, Baggs, Saratoga, and Encampment
419 AM MST Tue Jan 5 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow showers and areas of blowing and drifting snow
  expected. Light accumulations. Winds gusting up to 45 MPH. 
 
* WHERE...Lower elevations of Carbon County. 

* WHEN...5 AM until 5 PM MST today. 

* IMPACTS...Hazardous travel due to slick, snow covered roads and
  reduced visibilities in falling and blowing snow. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$

WYZ110-060000-
/O.CON.KCYS.WW.Y.0002.210105T1200Z-210106T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
419 AM MST Tue Jan 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow and blowing snow expected. Near zero visibilities
  possible at times. Total snow accumulations of up to 3 inches.
  Winds gusting as high as 65 MPH. 

* WHERE...Arlington and Elk Mountain along Interstate 80 between 
  Laramie and Rawlins.

* WHEN...5 AM until 5 PM MST today.

* IMPACTS...Dangerous or impossible travel conditions due to slick
  or snow covered roads and significantly reduced visibilities in
  falling and blowing snow. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$

CLH
272 
WWUS45 KCYS 052055
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
155 PM MST Tue Jan 5 2021

...IMPACTFUL WINTER WEATHER FOR AREAS WEST OF THE LARAMIE RANGE 
THIS AFTERNOON...

WYZ112-114-060000-
/O.CON.KCYS.WS.W.0001.000000T0000Z-210106T0000Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
155 PM MST Tue Jan 5 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of one to three
  inches. Total accumulations of 8 to 14 inches. Winds gusting as
  high as 55 mph.

* WHERE...Sierra Madre and Snowy Mountain Ranges.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Extremely dangerous or impossible mountain travel 
  due to icy, snow packed roads and near zero visibilities in 
  falling and blowing snow. Outdoor recreation will be life 
  threatening to those caught unprepared for severe winter 
  conditions.

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.

&&

$$

WYZ110-060000-
/O.CON.KCYS.WW.Y.0002.000000T0000Z-210106T0000Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
155 PM MST Tue Jan 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of up to one inch.
  Total snow accumulations of 2 to 5 inches. Winds gusting as 
  high as 60 mph.

* WHERE...Arlington and Elk Mountain along Interstate 80 between 
  Laramie and Rawlins.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Dangerous or impossible travel conditions due to slick 
  snow covered roads and significantly reduced visibilities in 
  falling and blowing snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$

WYZ104-105-109-111-113-060000-
/O.CON.KCYS.WW.Y.0002.000000T0000Z-210106T0000Z/
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Carbon County-Southwest Carbon County-
Upper North Platte River Basin-
Including the cities of Seminoe Dam, Medicine Bow, Shirley Basin,
Rawlins, Baggs, Saratoga, and Encampment
155 PM MST Tue Jan 5 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 5 PM MST THIS
AFTERNOON...

* WHAT...Snow. Additional snow accumulations of up to one inch.
  Total snow accumulations of 2 to 5 inches. Winds gusting as high
  as 45 mph.

* WHERE...Lower elevations of Carbon County.

* WHEN...Until 5 PM MST this afternoon.

* IMPACTS...Hazardous travel due to slick, snow covered roads 
  and reduced visibilities in falling and blowing snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. 

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

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 4, 12:53 AM MSTHigh Wind WarningCYSAlbany, Carbon, Laramie, Platte12 hr
Jan 4, 3:16 AM MSTHigh Wind WatchCYSAlbany, Carbon, Laramie, Platte16 hr
Jan 4, 3:43 AM MSTWinter Weather AdvisoryCYSAlbany, Carbon9 hr
Jan 4, 1:13 PM MSTHigh Wind WarningCYSAlbany, Carbon, Laramie, Platte30 hr

Nearby

Winter Storm Warnings in Wyoming, 2021Every winter storm 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.