Winter Storm Warning 14, NWS Cheyenne, WY

607 
WWUS45 KCYS 012033
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
233 PM MDT Sun Oct 1 2017

...Significant Accumulating Snowfall Likely Over the Higher
Elevations of Southeast Wyoming Tonight Through Monday Night...

WYZ116-021200-
/O.UPG.KCYS.WS.A.0014.171002T0000Z-171003T0600Z/
/O.EXB.KCYS.WS.W.0014.171002T0000Z-171003T0600Z/
South Laramie Range-
Including the cities of Buford, Pumpkin Vine, and Vedauwoo
233 PM MDT Sun Oct 1 2017

...WINTER STORM WARNING IN EFFECT FROM 6 PM THIS EVENING TO
MIDNIGHT MDT MONDAY NIGHT...

The National Weather Service in Cheyenne has issued a Winter
Storm Warning for heavy snowfall, which is in effect from 6 PM 
this evening to midnight MDT Monday night. The Winter Storm Watch 
is no longer in effect. 

* TIMING...Periods of snow will be possible this evening, but the
  snow will be on the increase late tonight, and may become heavy
  at times Monday before tapering off Monday night. 

* TOTAL SNOW ACCUMULATIONS...6 to 9 inches possible, with highest
  amounts over the Interstate 80 summit. 

* WINDS/VISIBILITY...Visibility may be reduced below one half 
  mile at times in falling snow. 

* IMPACTS...Mainly to travel, especially over the Interstate 80 
  Summit between Laramie and Cheyenne. Roads could become slick 
  and snow packed along with areas of low visibility. 

Precautionary/Preparedness actions...

A Winter Storm Watch means there is a potential for significant
snow that may impact travel. Continue to monitor the latest
forecasts.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for heavy snow means severe winter weather
conditions are expected or occurring.  Significant amounts of
snow are forecast that will make travel dangerous. Only travel in
an emergency. If you must travel...keep an extra flashlight...
food...and water in your vehicle in case of an emergency.


&&

$$

WYZ112-114-021200-
/O.CON.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-
Including the cities of Centennial and Albany
233 PM MDT Sun Oct 1 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT
MONDAY NIGHT...

* TIMING...Snow will become heavy at times tonight and Monday
  before tapering off late Monday night.  

* TOTAL SNOW ACCUMULATIONS...12 to 16 inches, especially above 
  9000 feet in the Snowy and Sierra Madre mountain ranges. 
  Locally higher amounts are possible. 

* WINDS/VISIBILITY...West winds of 10 to 20 MPH with higher gusts
  are expected. Visibilities may be reduced to less than one half
  mile at times in falling snow. 

* IMPACTS...Mainly to travel and outdoor recreation. Mountain 
  travel will be difficult or impossible with slick, snow packed 
  roads and low visibility. Those planning outdoor activities in 
  the Snowy and Sierra Madre mountain ranges should be prepared 
  for hazardous winter conditions. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for heavy snow means severe winter weather
conditions are expected or occurring.  Significant amounts of
snow are forecast that will make travel dangerous. Only travel in
an emergency. If you must travel...keep an extra flashlight...
food...and water in your vehicle in case of an emergency.

&&

$$

WYZ110-113-115-117-021200-
/O.NEW.KCYS.WW.Y.0027.171002T0900Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
233 PM MDT Sun Oct 1 2017

...WINTER WEATHER ADVISORY IN EFFECT FROM 3 AM MONDAY TO MIDNIGHT
MDT MONDAY NIGHT...

The National Weather Service in Cheyenne has issued a Winter
Weather Advisory for snowfall, which is in effect from 3 AM 
Monday to midnight MDT Monday night. 

* TIMING...Rain and snow mix can be expected this evening, before
  turning to all snow early Monday morning. Snow could be heavy 
  at times on Monday. 

* TOTAL SNOW ACCUMULATIONS...3 to 5 inches.

* WINDS/VISIBILITY...Visibility may be reduced to less than one 
  half mile at times in falling snow.
 
* IMPACTS...Roadways will become slick during the Monday morning
  commute and remain slick through much of the day. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means that periods of snow 
will cause travel difficulties. Be prepared for snow covered roads
and limited visibilities...and use caution while driving.


&&

$$

253 
WWUS45 KCYS 020301
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
901 PM MDT Sun Oct 1 2017

...Significant Accumulating Snowfall Likely Over the Higher
Elevations of Southeast Wyoming Tonight Through Monday Night...

WYZ112-114-116-021200-
/O.CON.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-South Laramie Range-
Including the cities of Centennial, Albany, Buford, Pumpkin Vine,
and Vedauwoo
901 PM MDT Sun Oct 1 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT
MONDAY NIGHT...

* TIMING...Periods of snow will develop late tonight, and will be 
  heavy at times Monday before tapering off Monday night. 

* TOTAL SNOW ACCUMULATIONS...10 to 16 inches, especially above
  9000 feet over the Snowy and Sierra Madre mountain ranges. 6 to
  9 inches over the South Laramie mountain range, heaviest over 
  the Interstate 80 summit. Locally higher amounts are possible. 

* WINDS/VISIBILITY...West to southwest winds 15 to 25 mph.
  Visibilities will be reduced below one half mile at times in 
  falling snow. 

* IMPACTS...Mainly to travel and outdoor recreation. Mountain
  travel will be difficult or impossible with slick, snow packed
  roads and low visibilities. Those planning outdoor activities 
  in the Snowy and Sierra Madre mountain ranges should be prepared
  for hazardous winter conditions. Travel over the Interstate 80 
  Summit between Laramie and Cheyenne will become difficult. Roads
  will become slick and snow packed along with areas of low 
  visibilities. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for heavy snow means severe winter weather
conditions are expected or occurring. Significant amounts of snow
are forecast that will make travel dangerous. Only travel in an 
emergency. If you must travel...keep an extra flashlight...food...
and water in your vehicle in case of an emergency.

&&

$$

WYZ110-113-115-117-021200-
/O.CON.KCYS.WW.Y.0027.171002T0900Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
901 PM MDT Sun Oct 1 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 3 AM MONDAY TO
MIDNIGHT MDT MONDAY NIGHT...

* TIMING...Mixed rain and snow will changeover to snow early
  Monday morning. Snow may be heavy at times Monday.

* TOTAL SNOW ACCUMULATIONS...3 to 6 inches.

* WINDS/VISIBILITY...Visibility may be reduced to less than one 
  half mile at times in falling snow. 

* IMPACTS...Roadways will become slick and hazardous Monday
  morning and continue through Monday evening. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory for snow means that periods of snow
will cause travel difficulties. Be prepared for snow covered
roads and limited visibilities...and use caution while driving.

&&

$$

707 
WWUS45 KCYS 020931
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
331 AM MDT Mon Oct 2 2017

...Significant Accumulating Snowfall Likely Over the Higher
Elevations of Southeast Wyoming Through This Evening...

WYZ112-114-116-022300-
/O.CON.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-South Laramie Range-
Including the cities of Centennial, Albany, Buford, Pumpkin Vine,
and Vedauwoo
331 AM MDT Mon Oct 2 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Heavy snow will re-develop this morning. Plan on
  difficult travel conditions, including during the evening
  commute. Additional snow accumulations of 4 to 8 inches are 
  expected.

* WHERE...Sierra Madre, Snowy, and South Laramie Ranges including
  the Interstate 80 Summit.

* WHEN...Until midnight tonight.

* ADDITIONAL DETAILS...Travel and outdoor recreation will be
  impacted. Mountain travel will be difficult or impossible with 
  slick, snow packed roads and low visibilities. Those planning 
  outdoor activities in the Snowy and Sierra Madre mountain ranges
  should be prepared for hazardous winter conditions. Travel over
  the Interstate 80 Summit between Laramie and Cheyenne will 
  become difficult. Roads will become slick and snow packed along 
  with areas of low visibilities. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for 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.

&&

$$

WYZ110-113-115-117-022300-
/O.CON.KCYS.WW.Y.0027.000000T0000Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
331 AM MDT Mon Oct 2 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Snow expected. Plan on slippery road conditions,
  including during the evening commute. Total snow accumulations
  of 3 to 6 inches, are expected.

* WHERE...North Snowy Range Foothills, Upper North Platte River
  Basin, Laramie Valley and South Laramie Range Foothills.

* WHEN...Until midnight tonight.

* ADDITIONAL DETAILS...Look for reduced visibilities at times.
  Roadways will become slick and hazardous Monday morning and
  continue through this evening. 

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.

&&

$$

HAHN

038 
WWUS45 KCYS 021455
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
855 AM MDT Mon Oct 2 2017

...Significant Accumulating Snowfall Likely Over the Higher
Elevations of Southeast Wyoming Through This Evening...

WYZ112-114-116-030000-
/O.CON.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-South Laramie Range-
Including the cities of Centennial, Albany, Buford, Pumpkin Vine,
and Vedauwoo
855 AM MDT Mon Oct 2 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Heavy snow occurring. Plan on difficult travel 
  conditions, including during the evening commute. Additional 
  snow accumulations of 4 to 6 inches, with localized amounts up 
  to 8 inches, are expected.

* WHERE...Sierra Madre Range, Snowy Range and South Laramie Range.

* WHEN...Until midnight.

* ADDITIONAL DETAILS...Look for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for 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.

&&

$$

WYZ110-113-115-117-030000-
/O.CON.KCYS.WW.Y.0027.000000T0000Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
855 AM MDT Mon Oct 2 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Snow occurring. Plan on slippery road conditions, 
  including during the evening commute. Additional snow 
  accumulations of 2 to 4 inches are expected.

* WHERE...North Snowy Range Foothills, Upper North Platte River
  Basin, Laramie Valley and South Laramie Range Foothills.

* WHEN...Until midnight.

* ADDITIONAL DETAILS...Look for reduced visibilities at times.

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.

&&

$$

929 
WWUS45 KCYS 022124
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
324 PM MDT Mon Oct 2 2017

...Significant Accumulating Snowfall Likely Over the Higher
Elevations of Southeast Wyoming Through This Evening...

WYZ112-114-116-030600-
/O.CON.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-South Laramie Range-
Including the cities of Centennial, Albany, Buford, Pumpkin Vine,
and Vedauwoo
324 PM MDT Mon Oct 2 2017

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Moderate to heavy snow still occurring. Plan on 
  difficult travel conditions, including during the evening 
  commute. Additional snow accumulations of 2 to 4 inches are 
  expected.

* WHERE...Sierra Madre, Snowy, and South Laramie Range.

* WHEN...Until midnight.

* ADDITIONAL DETAILS...Look for significant reductions in 
  visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning for 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.

&&

$$

WYZ110-113-115-117-030600-
/O.CON.KCYS.WW.Y.0027.000000T0000Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
324 PM MDT Mon Oct 2 2017

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL MIDNIGHT MDT
TONIGHT...

* WHAT...Snow continues late this afternoon. Plan on slippery 
  road conditions, including during the evening commute. 
  Additional snow accumulations of 1 to 3 inches are expected.

* WHERE...Laramie Valley, Upper North Platte River Basin, and
  South Laramie Range Foothills.

* WHEN...Until midnight.

* ADDITIONAL DETAILS...Look for reduced visibilities at times.

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.

&&

$$

465 
WWUS45 KCYS 030213
WSWCYS

URGENT - WINTER WEATHER MESSAGE
National Weather Service Cheyenne WY
813 PM MDT Mon Oct 2 2017

...SNOW HAS COME TO AN END ACROSS SOUTHEAST WYOMING...

WYZ112-114-116-030315-
/O.CAN.KCYS.WS.W.0014.000000T0000Z-171003T0600Z/
Sierra Madre Range-Snowy Range-South Laramie Range-
Including the cities of Centennial, Albany, Buford, Pumpkin Vine,
and Vedauwoo
813 PM MDT Mon Oct 2 2017

...WINTER STORM WARNING IS CANCELLED...

Snow has largely come to an end across the area. Light snow 
showers or flurries will still be possible through midnight, 
however any additional accumulation will be minimal.

$$

WYZ110-113-115-117-030315-
/O.CAN.KCYS.WW.Y.0027.000000T0000Z-171003T0600Z/
North Snowy Range Foothills-Upper North Platte River Basin-
Laramie Valley-South Laramie Range Foothills-
Including the cities of Arlington, Elk Mountain, Saratoga, 
Encampment, Bosler, Laramie, Whitaker, Federal, and Horse Creek
813 PM MDT Mon Oct 2 2017

...WINTER WEATHER ADVISORY IS CANCELLED...

Snow has largely come to an end across the area. Light snow 
showers or flurries will still be possible through midnight, 
however any additional accumulation will be minimal.

$$

Area Forecast Discussion
National Weather Service Cheyenne WY
326 PM MDT Sat Sep 30 2017

.SHORT TERM...(This evening through Monday night)
Issued at 335 PM MDT Sat Sep 30 2017

Main forecast concern in the short term period will be the
potential for the first significant snowfall of the season for a
few of our higher elevations.

For tonight, a lead shortwave currently seen on GOES 16 WV imagery
over western CO will traverse the area through the late evening
hours.  A small convective complex has formed over western CO in
association with this wave and some of this activity will likely get
into our mountain zones by late afternoon.  Hi-res guidance also
indicating some of this activity may hold together affect our
southern Panhandle counties this evening. With 500-1000 J/kg of
SBCAPE currently analyzed over the Panhandle, there is the potential
for a strong storm or two with small hail and gusty downdraft winds.

Sunday through Monday will be quite active.  A cold front will push
across the area during the morning and early afternoon hours on
Sunday.  Gusty W to NW winds are likely behind the front along and
west of I-25 but gradients are not quite as tight as earlier model
runs indicated so trimmed wind speeds back just a bit.  Vigorous
disturbance will dive into northern UT by Sunday night/early Monday.
A tight low level frontal zone will lie draped from SW to NE across
some part of our area through the period.  With the approach of the
strong disturbance and associated 120kt upper jet running parallel
to this frontal zone, think an area of relatively heavy
precipitation will set up.  Both the GFS and NAM are indicating
strong frontogenesis in this axis and although lapse rates aren't
the best, some negative values of EPV occur coincident with this
feature during the day on Monday.  Thus some banded precip looks
likely.  The greatest uncertainties are, how cold will the boundary
layer be and exactly where does the axis of heaviest precip set up?
Still a lot of spread between the guidance on the position of the
frontal zone so hard to pinpoint amounts at this time.  Felt
confident enough in temps and amounts though to issue a Winter Storm
Watch for the Sierra Madre and Snowy Ranges and for the South
Laramie Range mainly for transportation impacts near the I-80
summit.  With snow levels falling to around 7000 ft at the lowest,
think most of the lower elevations will be rain with a rain/snow mix
possible down to around 6000 ft.  There is the potential during the
heaviest band of precip for snowlevels to lower more than currently
forecast so areas such as the Laramie Valley and Arlington may
eventually have to be considered for winter headlines of some sort.

.LONG TERM...(Tuesday through Saturday)
Issued at 335 PM MDT Sat Sep 30 2017

Models in pretty good agreement with ejecting one upper low over
the northern plains Tuesday while leaving a second upper low over
the western CONUS, wobbling that one around through Thursday
before sliding it east across Wyoming into the central plains
Friday and Saturday. Short ridging move across the CWA Tuesday
through Wednesday boding for mainly dry conditions, though a few
showers not out of the question over the mtns given favorable swly
upper flow and any weak impulses. Pcpn looks to increase Thursday
night and Friday as the next upper low approaches with lower
elevation rain and some mtn snow. Mainly dry and somewhat windy
Saturday in the wake of the system.

&&

.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 335 PM MDT Sat Sep 30 2017

Mostly VFR through the period except at KRWL where some patchy
MVFR cigs are possible mainly after 06Z. Higher mtns likely will
be obscured with snow showers at times. Elsewhere scattered
showers should move across the area this evening with more
developing Sunday afternoon.

&&

.FIRE WEATHER...
Issued at 335 PM MDT Sat Sep 30 2017

Widespread precipitation and cool temperatures will
mitigate any fire weather concerns through at least Tuesday.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Winter Storm Watch from Sunday afternoon through Monday evening
     for WYZ112-114.

     Winter Storm Watch from Sunday evening through Monday evening
     for WYZ116.

NE...None.
&&

SHORT TERM...DEL
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...DEL

Hazardous Weather Outlook...CORRECTED
National Weather Service Cheyenne WY
905 PM MDT Sat Sep 30 2017

WYZ101>119-020315-
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-
North Snowy Range Foothills-Southwest Carbon County-
Sierra Madre Range-Upper North Platte River Basin-Snowy Range-
Laramie Valley-South Laramie Range-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
905 PM MDT Sat Sep 30 2017

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

.DAY ONE...TONIGHT

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

A series of upper disturbances and strong cold front will move
across Wyoming Sunday and Monday. Numerous rain showers and
isolated non-severe thunderstorms will accompany the cold front
Sunday. Much colder air will lower snow levels to 6500 feet by
Monday morning.

Rain will change to snow as early as Sunday afternoon over the
Snowy and Sierra Madre ranges, and Sunday evening over the
southern Laramie Range. Winter Storm Watches are in effect as
snow may be heavy at times, with significant accumulations
possible through Monday evening.

.Spotter information statement...

Spotter activation will not be required.

NEZ002-003-019>021-054-055-095-096-020315-
Dawes-Box Butte-Scotts Bluff-Banner-Morrill-Kimball-Cheyenne-
North Sioux-South Sioux-
905 PM MDT Sat Sep 30 2017

This hazardous weather outlook is for portions of western
Nebraska.

.DAY ONE...TONIGHT

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

Isolated thunderstorms will accompany a strong cold front Sunday
afternoon. Strong storms with small hail, gusty winds and brief
heavy rain will be possible across the southern Nebraska Panhandle.

.Spotter information statement...

Spotter activation will not be needed.