Alert archive / Wyoming / Wind Chill Advisories in 2017

Wind Chill Advisory 9, NWS Cheyenne, WY

December 25, 2017Converse County, Niobrara County, Wyoming; Dawes County, Sioux County, Nebraska

NWS Cheyenne, WY issued this wind chill advisory at Dec 25, 2017, 5:38 PM MST for Converse County, Niobrara County, Wyoming; Dawes County, Sioux County, Nebraska. It took effect at Dec 25, 2017, 11:00 PM MST. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Dec 25, 2017, 5:38 PM MST (00:38 UTC)
In effect from
Dec 25, 2017, 11:00 PM MST
Expired
Dec 26, 2017, 6:09 AM MST
In force
7 hr
Issued by
NWS Cheyenne, WY

Counties Dawes County, NE, Sioux County, NE, Converse County, WY, Niobrara County, WY

The radar

The Rapid City radar (KUDX), 184 km from the middle of the area, began a volume at 00:43 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

Rapid City, SD (KRAP), launched 00:00Z, 0.6 hours before the alert went out and 177 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, Rapid City, SD at 00:00Z on 2017-12-26Temperature 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 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 00:00Z on 2017-12-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 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
870 m above ground
0-6 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

651 
WWUS45 KCYS 260038
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
538 PM MST Mon Dec 25 2017

...BLOWING SNOW CONTINUING NEAR ARLINGTON AND ELK MOUNTAIN THIS
EVENING... 

...SNOW INCREASING ACROSS PORTIONS OF SOUTHEAST WYOMING AND THE
SOUTHERN NEBRASKA PANHANDLE... 

WYZ110-260600-
/O.CAN.KCYS.BZ.W.0002.000000T0000Z-171226T0600Z/
/O.EXA.KCYS.WW.Y.0039.000000T0000Z-171226T0600Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
538 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 PM MST THIS
EVENING...
...BLIZZARD WARNING IS CANCELLED...

* WHAT...Blowing snow expected. Plan on areas of poor visibilities
  and slick roadways to create difficult travel conditions at
  times. 

* WHERE...Interstate 80 between mile markers 240 and 285. 

* WHEN...Until 11 PM this evening. 

* ADDITIONAL DETAILS...Winds gusting as high as 55 mph will 
  cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for blowing snow means periods of
blowing snow will cause primarily travel difficulties. Be
prepared for snow covered roads and limited visibilities, and use
caution while driving. The latest road conditions for the state
you are calling from can be obtained by calling 5 1 1.

$$

NEZ095-260900-
/O.CAN.KCYS.WW.Y.0039.000000T0000Z-171226T0600Z/
/O.NEW.KCYS.WC.Y.0003.171226T0600Z-171226T1700Z/
North Sioux-
Including the city of Harrison
538 PM MST Mon Dec 25 2017

...WIND CHILL ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 10 AM
MST TUESDAY...
...WINTER WEATHER ADVISORY IS CANCELLED...

* WHAT...Very cold wind chills expected. The cold wind chills will
  cause frostbite in as little as 30 minutes to exposed skin.
  Expect wind chills as low as 25 below zero.

* WHERE...Northern Sioux county. 

* WHEN...11 PM this evening until 10 AM Tuesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Advisory means that cold air and the wind will
combine to create low wind chills. Frost bite and hypothermia can
occur if precautions are not taken. Make sure you wear a hat and
gloves.

$$

WYZ112-114-260900-
/O.CON.KCYS.WS.W.0020.000000T0000Z-171226T1300Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
538 PM MST Mon Dec 25 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 AM MST
TUESDAY...

* WHAT...Heavy snow and blowing snow occurring. Plan on 
  difficult travel conditions. Additional snow accumulations of 
  1 to 3 inches are expected.

* WHERE...Snowy and Sierra Madre Ranges.

* WHEN...Until 6 AM Tuesday.

* ADDITIONAL DETAILS...Winds gusting as high as 40 mph will 
  cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions are occurring. 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.

$$

NEZ002-WYZ101-102-260900-
/O.NEW.KCYS.WC.Y.0003.171226T0600Z-171226T1700Z/
Dawes-Converse County Lower Elevations-Niobrara County-
Including the cities of Chadron, Chadron St Park, Bill, Douglas, 
Deer Creek, Glenrock, Lusk, and Redbird
538 PM MST Mon Dec 25 2017

...WIND CHILL ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 10 AM
MST TUESDAY...

* WHAT...Very cold wind chills expected. The cold wind chills will
  cause frostbite in as little as 30 minutes to exposed skin.
  Expect wind chills as low as 25 below zero.

* WHERE...East central Wyoming and the northern Nebraska
  Panhandle. 

* WHEN...11 PM this evening until 10 AM Tuesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Advisory means that cold air and the wind will
combine to create low wind chills. Frost bite and hypothermia can
occur if precautions are not taken. Make sure you wear a hat and
gloves.

$$

WYZ117-118-260900-
/O.EXB.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
South Laramie Range Foothills-Central Laramie County-
Including the cities of Whitaker, Federal, Horse Creek, 
and Cheyenne
538 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 2 AM MST TUESDAY...

* WHAT...Snow expected. Plan on slippery road conditions and areas
  of low visibilities. Additional snow accumulations of 2 to 4 
  inches expected, with locally higher amounts up to 6 inches 
  possible.

* WHERE...Central Laramie county, including the city of Cheyenne.
  The heaviest snow is expected to fall over northern portions of
  Laramie county. 

* WHEN...Now through 2 AM Tuesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Cold wind chills as low as 15 below zero will cause 
  frostbite in as little as 30 minutes to exposed skin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

WYZ106-116-260900-
/O.EXT.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Central Laramie Range and Southwest Platte County-
South Laramie Range-
Including the cities of Bordeaux, Buford, Pumpkin Vine, 
and Vedauwoo
538 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 2 AM MST TUESDAY...

* WHAT...Snow occurring. Plan on slippery road conditions and
  areas of low visibilities. Additional snow accumulations of 2 
  to 4 inches expected, with locally higher amounts up to 6 inches
  possible.

* WHERE...Southwest Platte county.

* WHEN...Until 2 AM Tuesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Cold wind chills as low as 15 below zero will cause 
  frostbite in as little as 30 minutes to exposed skin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

NEZ003-019>021-054-055-096-WYZ107-108-119-260900-
/O.EXT.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
South Sioux-East Platte County-Goshen County-East Laramie County-
Including the cities of Alliance, Scottsbluff, Gering, 
Harrisburg, Angora, Bridgeport, Bayard, Redington, Kimball, 
Brownson, Sidney, Agate, Wheatland, Guernsey, Torrington, 
and Pine Bluffs
538 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY NOW IN EFFECT UNTIL 2 AM MST TUESDAY...

* WHAT...Snow increasing. Plan on slippery road conditions and
  areas of low visibilities. Additional snow accumulations of 2 
  to 4 inches expected, with locally higher amounts up to 6 inches
  possible.

* WHERE...Mainly along and southwest of a line from Torrington to
  Bridgeport. The heaviest snow is expected to fall just north of
  the Interstate 80 corridor in northern Laramie and Kimball
  counties. 

* WHEN...Until 2 AM Tuesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Cold wind chills as low as 20 below zero will cause 
  frostbite in as little as 30 minutes to exposed skin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

CLH
3 follow-up statements
189 
WWUS45 KCYS 260606
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
1106 PM MST Mon Dec 25 2017

...PERIODS OF SNOW ACROSS SOUTHEAST WYOMING AND THE WESTERN
NEBRASKA PANHANDLE THROUGH EARLY TUESDAY MORNING... 

WYZ110-260715-
/O.EXP.KCYS.WW.Y.0039.000000T0000Z-171226T0600Z/
North Snowy Range Foothills-
Including the cities of Arlington and Elk Mountain
1106 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY HAS EXPIRED...

Significant blowing snow has ended. However, motorists may still
encounter visibilities around one mile through the night in patchy
blowing snow. 

$$

WYZ112-114-261300-
/O.CON.KCYS.WS.W.0020.000000T0000Z-171226T1300Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
1106 PM MST Mon Dec 25 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 AM MST
TUESDAY...

* WHAT...Heavy snow and blowing snow occurring. Plan on 
  difficult travel conditions. Additional snow accumulations of 
  1 to 3 inches are expected.

* WHERE...Snowy and Sierra Madre Ranges.

* WHEN...Until 6 AM Tuesday.

* ADDITIONAL DETAILS...Winds gusting as high as 40 mph will 
  cause areas of blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions are occurring. 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.

$$

WYZ106-116-260900-
/O.CON.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Central Laramie Range and Southwest Platte County-
South Laramie Range-
Including the cities of Bordeaux, Buford, Pumpkin Vine, 
and Vedauwoo
1106 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 AM MST
TUESDAY...

* WHAT...Snow occurring. Plan on slippery road conditions and
  areas of low visibilities. 

* WHERE...Southwest Platte county.

* WHEN...Until 2 AM Tuesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Cold wind chills as low as 15 below zero will cause 
  frostbite in as little as 30 minutes to exposed skin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for blowing snow means that
visibilities will be limited due to strong winds blowing snow
around. Use caution when traveling, especially in open areas. The
latest road conditions for the state you are calling from can be
obtained by calling 5 1 1.

$$

NEZ003-019>021-054-055-096-WYZ107-108-117>119-260900-
/O.CON.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
South Sioux-East Platte County-Goshen County-
South Laramie Range Foothills-Central Laramie County-
East Laramie County-
Including the cities of Alliance, Scottsbluff, Gering, 
Harrisburg, Angora, Bridgeport, Bayard, Redington, Kimball, 
Brownson, Sidney, Agate, Wheatland, Guernsey, Torrington, 
Whitaker, Federal, Horse Creek, Cheyenne, and Pine Bluffs
1106 PM MST Mon Dec 25 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 2 AM MST
TUESDAY...

* WHAT...Periods of snow. Plan on slippery road conditions and
  areas of low visibilities. Additional snow accumulations will be
  less than one inch. 

* WHERE...High plains of southeast Wyoming and the western
  Nebraska Panhandle. 

* WHEN...Until 2 AM Tuesday.

* ADDITIONAL DETAILS...Be prepared for reduced visibilities at 
  times. Cold wind chills as low as 20 below zero will cause 
  frostbite in as little as 30 minutes to exposed skin.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means periods of snow will
cause primarily travel difficulties. Be prepared for snow covered
roads and limited visibilities, and use caution while driving.
The latest road conditions for the state you are calling from can
be obtained by calling 5 1 1.

$$

NEZ002-095-WYZ101-102-261415-
/O.CON.KCYS.WC.Y.0003.000000T0000Z-171226T1700Z/
Dawes-North Sioux-Converse County Lower Elevations-
Niobrara County-
Including the cities of Chadron, Chadron St Park, Harrison, Bill,
Douglas, Deer Creek, Glenrock, Lusk, and Redbird
1106 PM MST Mon Dec 25 2017

...WIND CHILL ADVISORY REMAINS IN EFFECT UNTIL 10 AM MST
TUESDAY...

* WHAT...Very cold wind chills expected. The cold wind chills 
  will cause frostbite in as little as 30 minutes to exposed 
  skin. Expect wind chills as low as 25 below zero.

* WHERE...Northern Sioux county.

* WHEN...11 PM this evening until 10 AM Tuesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Advisory means that cold air and the wind will
combine to create low wind chills. Frost bite and hypothermia can
occur if precautions are not taken. Make sure you wear a hat and
gloves.

$$
359 
WWUS45 KCYS 260855
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
155 AM MST Tue Dec 26 2017

...SNOW TAPERING OFF EARLY THIS MORNING ACROSS SOUTHEAST WYOMING 
AND THE WESTERN NEBRASKA PANHANDLE...

WYZ106-116-261000-
/O.EXP.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Central Laramie Range and Southwest Platte County-
South Laramie Range-
Including the cities of Bordeaux, Buford, Pumpkin Vine, 
and Vedauwoo
155 AM MST Tue Dec 26 2017

...WINTER WEATHER ADVISORY WILL EXPIRE AT 2 AM MST EARLY THIS
MORNING...

Snow is tapering off over the area early this morning. Some areas
of light snow and flurries will persist this morning but little if
any additional accumulations are anticipated. 

$$

NEZ003-019>021-054-055-096-WYZ107-108-117>119-261000-
/O.EXP.KCYS.WW.Y.0039.000000T0000Z-171226T0900Z/
Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
South Sioux-East Platte County-Goshen County-
South Laramie Range Foothills-Central Laramie County-
East Laramie County-
Including the cities of Alliance, Scottsbluff, Gering, 
Harrisburg, Angora, Bridgeport, Bayard, Redington, Kimball, 
Brownson, Sidney, Agate, Wheatland, Guernsey, Torrington, 
Whitaker, Federal, Horse Creek, Cheyenne, and Pine Bluffs
155 AM MST Tue Dec 26 2017

...WINTER WEATHER ADVISORY WILL EXPIRE AT 2 AM MST EARLY THIS
MORNING...

Snow is tapering off over the area early this morning. Some areas
of light snow and flurries will persist this morning but little if
any additional accumulations are anticipated. 

$$

WYZ112-114-261300-
/O.CON.KCYS.WS.W.0020.000000T0000Z-171226T1300Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
155 AM MST Tue Dec 26 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 6 AM MST EARLY
THIS MORNING...

* WHAT...Snow and blowing snow occurring. Plan on difficult 
  travel conditions. Additional snow accumulations of 1 to 3 
  inches are expected. 

* WHERE...Snowy and Sierra Madre Ranges.

* WHEN...Until 6 AM this morning.

* ADDITIONAL DETAILS...Winds gusting as high as 40 mph will 
  cause areas of blowing and drifting snow. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for snow and blowing snow means severe
winter weather conditions are occurring. 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.

$$

NEZ002-095-WYZ101-102-261700-
/O.CON.KCYS.WC.Y.0003.000000T0000Z-171226T1700Z/
Dawes-North Sioux-Converse County Lower Elevations-
Niobrara County-
Including the cities of Chadron, Chadron St Park, Harrison, Bill,
Douglas, Deer Creek, Glenrock, Lusk, and Redbird
155 AM MST Tue Dec 26 2017

...WIND CHILL ADVISORY REMAINS IN EFFECT UNTIL 10 AM MST THIS
MORNING...

* WHAT...Very cold wind chills expected. The cold wind chills 
  will cause frostbite in as little as 30 minutes to exposed 
  skin. Expect wind chills as low as 25 below zero. 

* WHERE...East central Wyoming and the northern Nebraska 
  Panhandle.

* WHEN...Until 10 AM Tuesday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Advisory means that cold air and the wind will
combine to create low wind chills. Frost bite and hypothermia can
occur if precautions are not taken. Make sure you wear a hat and
gloves.

$$
228 
WWUS45 KCYS 261309
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
609 AM MST Tue Dec 26 2017

WYZ112-114-261415-
/O.EXP.KCYS.WS.W.0020.000000T0000Z-171226T1300Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
609 AM MST Tue Dec 26 2017

...WINTER STORM WARNING HAS EXPIRED...

Snow and wind has diminished over the area this morning. There
will still be some snow showers into this afternoon but little
additional accumulation is expected.

$$

NEZ002-095-WYZ101-102-261415-
/O.CAN.KCYS.WC.Y.0003.000000T0000Z-171226T1700Z/
Dawes-North Sioux-Converse County Lower Elevations-
Niobrara County-
Including the cities of Chadron, Chadron St Park, Harrison, Bill,
Douglas, Deer Creek, Glenrock, Lusk, and Redbird
609 AM MST Tue Dec 26 2017

...WIND CHILL ADVISORY IS CANCELLED...

Wind chills have remained generally in the zero to 10 below zero
range this morning and dangerous wind chills are no longer
expected.

$$

What forecasters said that day

The local office's own words before this wind chill advisory 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 wind chill advisory went out at Dec 25, 2:51 PM MST, 2 hours 47 minutes earlier.

Area forecast discussion, Dec 25, 2:51 PM MST, 2 hours 47 minutes before
Area Forecast Discussion
National Weather Service Cheyenne WY
251 PM MST Mon Dec 25 2017

.SHORT TERM...(This evening through Tuesday night)
Issued at 200 PM MST Mon Dec 25 2017

Tricky forecast for late this afternoon and evening. Forecast
challenges continue to deal with snow locations and amounts.

Currently...Frontal boundary stalled over our southwestern CWFA
this afternoon, currently laying over southern Albany
County...through central Carbon County and then west over
southwestern WYoming this afternoon. Along and west of this front,
snow has stopped and temperatures have climbed into the low to mid
30s. East of this front, we are seeing very cold temperatures with
single digits in the Panhandle and the eastern plains of southeast
Wyoming. First upper shortwave moved through the area this
morning, bringing fairly widespread snow to many areas. Back edge
moving into the Panhandle this afternoon with snow really tapering
off behind.

To our west, water vapor imagery continues to show another weak
shortwave near Riverton this afternoon moving east. Question is,
what is this shortwave going to do once it interacts with the
stalled boundary out west?

Latest guidance in good agreement with the boundary slowly inching
eastward late this afternoon and evening. Area of snow developing
over the eastern plains as the shortwave to our west gets closer.
Looks like a band of light to moderate snow develops from the
southern nebraska Panhandle, northwestward to Wheatland this
evening that persists into the early morning hours Tuesday. Given
the extreme cold temperatures, snow ratios are going to be quite
high, on the order of 20 to 25 to 1, so accumulations are still
expected along that band. strong winds continuing out by Arlington
this evening, so kept the Blizzard Warning going out there.

Not seeing a whole lot of snow for Converse/Niobrara and Laramie
Counties late this afternoon and evening. Looking at the latest
short term guidance (HRRR), the band stays north of Cheyenne and
south of Converse/Niobrara Counties, so went ahead and cancelled
the Advisories for these counties. Evening shift will need to
monitor trends closely tonight and make last minute adjustments as
needed.

Lift from upper shortwave may persists into Tuesday morning
before subsidence returns mid morning. Low levels winds shift
easterly Tuesday afternoon, effectively washing out the boundary
towards 00Z Wednesday. Seeing only slight warming in 700mb
temperatures Tuesday, with single digit highs for the Panhandle
and eastern Wyoming plains.

.LONG TERM...(Wednesday through Sunday)
Issued at 300 AM MST Mon Dec 25 2017

Northwesterly upper flow will persist over the region through the
period with several impulses moving by in the flow. The arctic front
likely will oscillate ne and sw in response to these impulses with
some snow behind the front. Timing of these frontal shifts will be
the main difficulty. One push of cooler air looks to arrive Thursday
with the next surge on Saturday. Best chances for snow will be over
the northeast parts of the CWA Friday night and Saturday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 251 PM MST Mon Dec 25 2017

Tough forecast on the aviation desk today. Snow lingering in the
east from Chadron south to Alliance and Sidney will see a break
for a bit going into late afternoon, then more snow developing
this evening as the next shortwave moves in from the east.
Snowbands also increasing around Cheyenne and that band should
move off to the east affecting the southern Panhandle through late
evening. So, will see less snow and lower ceilings around Rawlins,
MVFR visibility/ceilings Laramie and Cheyenne through mid evening
with periods of IFR visibility, and more persistent IFR conditions
over the central and southern Nebraska Panhandle this evening as
that next band of snow sets up (as advertised in the higher
resolution models).

&&

.FIRE WEATHER...
Issued at 300 AM MST Mon Dec 25 2017

No fire weather concerns this week. A upper level weather disturbance
and Arctic cold front stalled along the Laramie Range will produce
more snowfall and cold temperatures through tonight. Strong west
to northwest winds will create blizzard conditions for the
Arlington and Elk Mountain areas with blowing and drifting snow.
The southern Wyoming mountains can expect heavy snow accumulations
as well as areas of blowing and drifting snow. Moderate snow
accumulations are forecast for the surrounding valleys as well as
areas east of Interstate 25. Cold temperatures Tuesday will
moderate Wednesday and Thursday. Another surge of very cold air
will spread southwest into the northeast plains Friday.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Weather Advisory until 11 PM MST this evening for
     WYZ106>108-116-119.

     Winter Storm Warning until 6 AM MST Tuesday for WYZ112-114.

     Blizzard Warning until 11 PM MST this evening for WYZ110.

NE...Winter Weather Advisory until 11 PM MST this evening for NEZ003-
     019>021-054-055-095-096.

&&

SHORT TERM...GCC
LONG TERM...RE
AVIATION...JG
FIRE WEATHER...GCC
Hazardous weather outlook, Dec 25, 3:35 AM MST, 14 hours 3 minutes before
Hazardous Weather Outlook
National Weather Service Cheyenne WY
335 AM MST Mon Dec 25 2017

WYZ110-112-114-261100-
North Snowy Range Foothills-Sierra Madre Range-Snowy Range-
335 AM MST Mon Dec 25 2017

This hazardous weather outlook is for portions of south central
Wyoming.

.DAY ONE...TODAY AND TONIGHT

Snow, heavy at times, will fall over the area today into this
evening. Locally strong winds will also occur which should create
areas of blizzard or near blizzard conditions. The snow should end
slowly tonight.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

Snow showers will occur at times through Saturday.

.Spotter information statement...

Spotter activation will not be needed.

NEZ002-003-019>021-054-055-095-096-WYZ101>109-111-113-115>119-
261100-
Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
North Sioux-South Sioux-Converse County Lower Elevations-
Niobrara County-North Laramie Range-
Ferris/Seminoe/Shirley Mountains-Shirley Basin-
Central Laramie Range and Southwest Platte County-
East Platte County-Goshen County-Central Carbon County-
Southwest Carbon County-Upper North Platte River Basin-
Laramie Valley-South Laramie Range-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
335 AM MST Mon Dec 25 2017

This hazardous weather outlook is for portions of western
Nebraska...east central Wyoming...south central Wyoming and
southeast Wyoming.

.DAY ONE...TODAY AND TONIGHT

Snow is expected to spread across the area this morning and
continue into this evening. Accumulating snow is likely over many
areas which will create hazardous driving conditions due to slick
roads and low visibilities.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

The probability for widespread hazardous weather is low.

.Spotter information statement...

Spotter activation will not be needed.

In the hours before

Local storm report, Dec 25, 12:30 PM MST, 5 hours 8 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
1230 PM MST MON DEC 25 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1000 AM     SNOW             19 WSW ENCAMPMENT       41.10N 107.13W
12/25/2017  E10.5 INCH       CARBON             WY   PARK/FOREST SRVC

            DIVIDE PEAK SNOTEL IN THE SIERRA MADRE RANGE.  ELEVATION
            8880 FEET.  SNOW WATER EQUIVALENT IS 0.7 INCHES AND THE
            SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS
            OVER PAST 11 HOURS.

1000 AM     SNOW             17 SW ENCAMPMENT        41.03N 107.03W
12/25/2017  E4.5 INCH        CARBON             WY   PARK/FOREST SRVC

            SANDSTONE RANGER STATION SNOTEL IN THE SIERRA MADRE
            RANGE.  ELEVATION 8150 FEET.  SNOW WATER EQUIVALENT IS
            0.3 INCHES AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1.
            ACCUMULATION WAS OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       10 WSW ENCAMPMENT       41.15N 106.97W
12/25/2017  M12.0 INCH       CARBON             WY   PARK/FOREST SRVC

            OLD BATTLE SNOTEL IN THE SIERRA MADRE RANGE.  ELEVATION
            10000 FEET.  SNOW WATER EQUIVALENT IS 0.6 INCHES AND THE
            SNOW TO LIQUID RATIO USED WAS 20 TO 1. ACCUMULATION WAS
            OVER PAST 11 HOURS.

1000 AM     SNOW             5 SW ENCAMPMENT         41.16N 106.86W
12/25/2017  E6.4 INCH        CARBON             WY   PARK/FOREST SRVC

            WEBBER SPRINGS SNOTEL IN THE SIERRA MADRE RANGE.
            ELEVATION 9250 FEET. SNOW WATER EQUIVALENT IS 0.4 INCHES
            AND THE SNOW TO LIQUID RATIO USED WAS 18 TO 1.
            ACCUMULATION WAS OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       10 SW ENCAMPMENT        41.11N 106.93W
12/25/2017  E12.0 INCH       CARBON             WY   PARK/FOREST SRVC

            LITTLE SNAKE RIVER SNOTEL IN THE SIERRA MADRE RANGE.
            ELEVATION 8915 FEET.  SNOW WATER EQUIVALENT IS 0.8 INCHES
            AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1.
            ACCUMULATION WAS OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       28 E SAVERY             41.02N 106.91W
12/25/2017  E12.0 INCH       CARBON             WY   PARK/FOREST SRVC

            WHISKEY PARK SNOTEL IN THE SIERRA MADRE RANGE.  ELEVATION
            8950 FEET.  SNOW WATER EQUIVALENT IS 0.8 INCHES AND THE
            SNOW TO LIQUID RATIO USED WAS 15 TO 1. ACCUMULATION WAS
            OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       11 SSE ENCAMPMENT       41.06N 106.71W
12/25/2017  E14.0 INCH       CARBON             WY   PARK/FOREST SRVC

            BLACKHALL MOUNTAIN SNOTEL IN THE SIERRA MADRE RANGE.
            ELEVATION 9820 FEET.  SNOW WATER EQUIVALENT IS 0.7 INCHES
            AND THE SNOW TO LIQUID RATIO USED WAS 20 TO 1.
            ACCUMULATION WAS OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       12 WNW CENTENNIAL       41.37N 106.32W
12/25/2017  E20.0 INCH       ALBANY             WY   PARK/FOREST SRVC

            NORTH FRENCH CREEK SNOTEL IN THE SNOWY RANGE.  ELEVATION
            10130 FEET.  SNOW WATER EQUIVALENT IS 1.0 INCHES AND THE
            SNOW TO LIQUID RATIO USED WAS 20 TO 1. ACCUMULATION WAS
            OVER PAST 11 HOURS.

1000 AM     HEAVY SNOW       30 WNW LARAMIE          41.48N 106.12W
12/25/2017  E14.0 INCH       CARBON             WY   PARK/FOREST SRVC

            SAND LAKE SNOTEL IN THE SNOWY RANGE.  ELEVATION 10050
            FEET.  SNOW WATER EQUIVALENT IS 0.7 INCHES AND THE SNOW
            TO LIQUID RATIO USED WAS 20 TO 1. ACCUMULATION WAS OVER
            PAST 11 HOURS.

1000 AM     HEAVY SNOW       7 NW CENTENNIAL         41.37N 106.21W
12/25/2017  E20.0 INCH       ALBANY             WY   PARK/FOREST SRVC

            BROOKLYN LAKE SNOTEL IN THE SNOWY RANGE.  ELEVATION 10240
            FEET.  SNOW WATER EQUIVALENT IS 1.0 INCHES AND THE SNOW
            TO LIQUID RATIO USED WAS 20 TO 1. ACCUMULATION WAS OVER
            PAST 11 HOURS.

1000 AM     HEAVY SNOW       6 SW CENTENNIAL         41.24N 106.19W
12/25/2017  E22.0 INCH       ALBANY             WY   PARK/FOREST SRVC

            CINNABAR PARK SNOTEL IN THE SNOWY RANGE.  ELEVATION 9574
            FEET.  SNOW WATER EQUIVALENT IS 1.1 INCHES AND THE SNOW
            TO LIQUID RATIO USED WAS 20 TO 1. ACCUMULATION WAS OVER
            PAST 11 HOURS.

1000 AM     HEAVY SNOW       21 SSE ELK MOUNTAIN     41.41N 106.26W
12/25/2017  E26.0 INCH       CARBON             WY   PARK/FOREST SRVC

            MEDICINE BOW SNOTEL IN THE SNOWY RANGE.  ELEVATION 10500
            FEET.  SNOW WATER EQUIVALENT IS 1.3 INCHES AND THE SNOW
            TO LIQUID RATIO USED WAS 20 TO 1.  ACCUMULATION WAS OVER
            PAST 11 HOURS.

1000 AM     SNOW             35 S RAWLINS            41.28N 107.23W
12/25/2017  E4.5 INCH        CARBON             WY   PARK/FOREST SRVC

            SAGE CREEK BASIN SNOTEL IN THE SIERRA MADRE RANGE.
            ELEVATION 7850 FEET. SNOW WATER EQUIVALENT IS 0.3 INCHES
            AND THE SNOW TO LIQUID RATIO USED WAS 15 TO 1.
            ACCUMULATION WAS OVER PAST 11 HOURS.

&&

HAMMER
Local storm report, Dec 25, 4:07 PM MST, 1 hour 31 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
407 PM MST MON DEC 25 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1055 AM     BLIZZARD         ARLINGTON               41.59N 106.21W
12/25/2017                   CARBON             WY   DEPT OF HIGHWAYS

            VISIBILITY UNDER 1/4 MILE WITH WIND GUSTS TO 56 MPH OVER
            PAST HOUR. PEAK GUST 60 MPH AT 850 AM.

0406 PM     SNOW             SCOTTSBLUFF             41.87N 103.66W
12/25/2017  E4.0 INCH        SCOTTS BLUFF       NE   PUBLIC

0406 PM     SNOW             BRIDGEPORT              41.67N 103.10W
12/25/2017  E3.0 INCH        MORRILL            NE   PUBLIC

&&

GCLAYCOM

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 26, 12:39 PM MSTHigh Wind WarningCYSAlbany, Carbon, Laramie, Platte4 days
Dec 26, 12:47 PM MSTWind Chill AdvisoryCYSConverse, Goshen, Laramie, Niobrara19 hr

Nearby

Wind Chill Advisories in Wyoming, 2017Wind Chill Advisories in Nebraska, 2017Every wind chill advisory in 2017

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.