Alert archive / Wyoming / Winter Storm Warnings in 2021

Winter Storm Warning 13, NWS Cheyenne, WY

April 27, 2021Albany County, Carbon County, Wyoming

NWS Cheyenne, WY issued this winter storm warning at Apr 27, 2021, 2:34 AM MDT for Albany County, Carbon County, Wyoming. It took effect at Apr 27, 2021, 12:00 PM MDT. It was in force for 18 hr. 8 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
Apr 27, 2021, 2:34 AM MDT (08:34 UTC)
In effect from
Apr 27, 2021, 12:00 PM MDT
Expired
Apr 28, 2021, 6:00 AM MDT
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 08:33 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
Apr 28, 3:00 AM MDTSNOW 42 Nw Jack Creek Campgro, WYDIVIDE PEAK SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 8880 FEET. SNOW WATER EQUIVALENT IS 0.4 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 42 Se Yellow Pine Campgr, WYCROW CREEK SNOTEL IN THE LARAMIE RANGE. ELEVATION 8330 FEET. SNOW WATER EQUIVALENT IS 0.4 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 4.8W Deep Creek Campground, WYSAND LAKE SNOTEL IN THE SNOWY RANGE. ELEVATION 10050 FEET. SNOW WATER EQUIVALENT IS 0.4 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 63 Wnw Sugar Loaf Campgr, WYMEDICINE BOW SNOTEL IN THE SNOWY RANGE. ELEVATION 10500 FEET. SNOW WATER EQUIVALENT IS 0.5 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 65 Wsw Sugar Loaf Campgr, WYNORTH FRENCH CREEK SNOTEL IN THE SNOWY RANGE. ELEVATION 10130 FEET. SNOW WATER EQUIVALENT IS 0.5 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 12 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 72 E Battle Lake, WYOLD BATTLE SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 10000 FEET. SNOW WATER EQUIVALENT IS 0.7 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 98 Ene Hog Park Campgrou, WYBLACKHALL MOUNTAIN SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 9820 FEET. SNOW WATER EQUIVALENT IS 0.9 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 15 HOURS.
Apr 28, 3:00 AM MDTSNOW 102 Wsw Bottle Creek Camp, WYWEBBER SPRINGS SNOTEL IN THE SIERRA MADRE RANGE. ELEVATION 9250 FEET. SNOW WATER EQUIVALENT IS 1.0 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 10 TO 1. ACCUMULATION WAS OVER PAST 15 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 00:00Z, 8.6 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 2021-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 joules per kilogram.LCLLFCEL10008507005003002001001 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 2021-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 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
2 J/kg
Mixed-layer CIN
-130 J/kg
Mixed-layer LCL
1570 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
98 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

687 
WWUS45 KCYS 270834
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
234 AM MDT Tue Apr 27 2021

...ACCUMULATING SNOW LIKELY FOR THE SOUTHEAST WYOMING MOUNTAINS
THIS AFTERNOON THROUGH LATE TONIGHT...

WYZ114-272200-
/O.UPG.KCYS.WS.A.0007.210428T0000Z-210428T1500Z/
/O.NEW.KCYS.WS.W.0013.210427T1800Z-210428T1200Z/
Snowy Range-
Including the cities of Centennial and Albany
234 AM MDT Tue Apr 27 2021

...WINTER STORM WARNING IN EFFECT FROM NOON TODAY TO 6 AM MDT
WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 14
  inches, heaviest above 9500 feet.

* WHERE...Snowy Range including Albany and Centennial.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous
  conditions could impact the evening commute. Heavy mountain snow
  could lead to hikers and outdoor enthusiasts becoming disoriented.

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.

&&

$$

WYZ116-272200-
/O.UPG.KCYS.WS.A.0007.210428T0000Z-210428T1500Z/
/O.NEW.KCYS.WW.Y.0030.210427T1800Z-210428T1200Z/
South Laramie Range-
Including the cities of Buford, Pumpkin Vine, and Vedauwoo
234 AM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM NOON TODAY TO 6 AM MDT
WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 6 inches.

* WHERE...South Laramie Range including Buford, Vedauwoo and the
  Interstate 80 Summit.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous
  conditions could impact the 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.

&&

$$

WYZ112-272200-
/O.NEW.KCYS.WW.Y.0030.210427T1800Z-210428T1200Z/
Sierra Madre Range-
234 AM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM NOON TODAY TO 6 AM MDT
WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 4 to 8 inches.

* WHERE...Sierra Madre Range.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the 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.

&&

$$
2 follow-up statements
079 
WWUS45 KCYS 272125
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
325 PM MDT Tue Apr 27 2021

...ACCUMULATING SNOW LIKELY FOR THE SOUTHEAST WYOMING MOUNTAINS
THIS AFTERNOON THROUGH LATE TONIGHT...

WYZ114-281100-
/O.CON.KCYS.WS.W.0013.000000T0000Z-210428T1200Z/
Snowy Range-
Including the cities of Centennial and Albany
325 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 AM MDT
WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 
  14 inches, heaviest above 9500 feet.

* WHERE...Snowy Range including Albany and Centennial.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the evening commute. Heavy mountain 
  snow could lead to hikers and outdoor enthusiasts becoming 
  disoriented.

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.

&&

$$

WYZ112-116-281100-
/O.CON.KCYS.WW.Y.0030.000000T0000Z-210428T1200Z/
Sierra Madre Range-South Laramie Range-
Including the cities of Buford, Pumpkin Vine, and Vedauwoo
325 PM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 AM MDT
WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 6 
  inches.

* WHERE...South Laramie Range including Buford, Vedauwoo and the 
  Interstate 80 Summit.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the 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.

&&

$$
812 
WWUS45 KCYS 280326
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
926 PM MDT Tue Apr 27 2021

...ACCUMULATING SNOW LIKELY FOR THE SOUTHEAST WYOMING MOUNTAINS
AND FOOTHILLS THROUGH LATE TONIGHT...

WYZ114-281130-
/O.CON.KCYS.WS.W.0013.000000T0000Z-210428T1200Z/
Snowy Range-
Including the cities of Centennial and Albany
926 PM MDT Tue Apr 27 2021

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 AM MDT
WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations of 7 to 
  14 inches, heaviest above 9500 feet.

* WHERE...Snowy Range including Albany and Centennial.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the evening commute. Heavy mountain 
  snow could lead to hikers and outdoor enthusiasts becoming 
  disoriented.

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.

&&

$$

WYZ117-281130-
/O.EXA.KCYS.WW.Y.0030.000000T0000Z-210428T1200Z/
South Laramie Range Foothills-
Including the cities of Whitaker, Federal, and Horse Creek
926 PM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 6 AM MDT WEDNESDAY...

* WHAT...Wet snow. Total snow accumulation of 1 to 3 inches,
  mainly above 6500 feet. 

* WHERE...Southern Laramie Range Foothills. 

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions due to slushy and
  partially snow covered roads.

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.

&&

$$

WYZ112-116-281130-
/O.CON.KCYS.WW.Y.0030.000000T0000Z-210428T1200Z/
Sierra Madre Range-South Laramie Range-
Including the cities of Buford, Pumpkin Vine, and Vedauwoo
926 PM MDT Tue Apr 27 2021

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 AM MDT
WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations of 3 to 6 
  inches.

* WHERE...South Laramie Range including Buford, Vedauwoo and the 
  Interstate 80 Summit.

* WHEN...From noon today to 6 AM MDT Wednesday.

* IMPACTS...Plan on slippery road conditions. The hazardous 
  conditions could impact the 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.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 27, 2:34 AM MDTWinter Weather AdvisoryCYSAlbany, Carbon, Laramie27 hr
Apr 27, 2:00 PM MDTSpecial Weather StatementCYSAlbany30 min

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.