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Wind Chill Warning


URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
516 AM MST Tue Feb 20 2018

...Wind Chill Warning for much of Natrona County this Morning...

.The combination of temperatures 10 below to 15 below zero, and
winds of 5 to 15 mph will result in wind chills between 25 and 40
below zero this morning.

WYZ020-201700-
/O.NEW.KRIW.WC.W.0001.180220T1216Z-180220T1700Z/
Natrona County Lower Elevations-
Including the city of Casper
516 AM MST Tue Feb 20 2018

...WIND CHILL WARNING IN EFFECT UNTIL 10 AM MST THIS MORNING...

* WHAT...Dangerously cold wind chills expected. Expect wind chills
  as low as 30 to 40 below zero.

* WHERE...Natrona County Lower Elevations.

* WHEN...Until 10 AM MST this morning.

* ADDITIONAL DETAILS...The dangerously cold wind chills could
  cause frostbite on exposed skin in as little as 10 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Wind Chill Warning means the combination of very cold air and
the wind will create dangerously low wind chill values. Frostbite
can occur quickly and even hypothermia or death if precautions
are not taken.

&&

$$

21

For more information from the National Weather Service visit
http://weather.gov/riw


Wind Chill Advisory


URGENT - WINTER WEATHER MESSAGE
National Weather Service Rapid City SD
535 AM MST Tue Feb 20 2018

.The heaviest snowfall with the winter storm has now moved east
of the area. Arctic air over the area this morning will produce
wind chills of 25 below to 35 below zero over southern portions of
northeast Wyoming.

WYZ055-058-201600-
/O.CON.KUNR.WC.Y.0007.000000T0000Z-180220T1600Z/
Southern Campbell-Weston-
Including the cities of Wright, Newcastle, and Upton
535 AM MST Tue Feb 20 2018

...WIND CHILL ADVISORY REMAINS IN EFFECT UNTIL 9 AM MST THIS
MORNING...

* WHAT...Very cold wind chills expected. Expect wind chills as
  low as 35 below zero.

* WHERE...Southern Campbell County and the Weston County Plains.

* WHEN...Until 9 AM MST this morning.

* ADDITIONAL DETAILS...The cold wind chills could cause
  frostbite on exposed skin in as little as 30 minutes.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A wind chill advisory means the combination of wind and cold
temperatures will create dangerously low wind chill values. If
you go outside, cover all parts of your body, especially your
head, face, and hands.

&&

$$


Special Weather Statement


Special Weather Statement
National Weather Service Riverton WY
1120 PM MST Mon Feb 19 2018

WYZ001>020-022>030-201600-
Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Big Horn Basin-Southwest Big Horn Basin-
Southeast Big Horn Basin-Owl Creek and Bridger Mountains-
Bighorn Mountains West-Bighorn Mountains Southeast-
Northeast Johnson County-Southeast Johnson County-
Teton and Gros Ventre Mountains-Jackson Hole-
Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
Including the cities of Lake, Mammoth, Old Faithful, Cody,
Meeteetse, Thermopolis, Worland, Buffalo, Kaycee, Jackson,
Dubois, Riverton, Shoshoni, Lander, Jeffrey City, Casper, Afton,
Alpine, Star Valley Ranch, Thayne, Pinedale, La Barge, Big Piney,
Farson, Kemmerer, Cokeville, Rock Springs, Green River,
and Wamsutter
1120 PM MST Mon Feb 19 2018

...Bitter Cold Temperatures in Place for the Next Couple of
Days...

Behind the exiting Arctic cold front and clearing skies, temperatures
will fall rapidly. Much of the region will range from 5 to 25
below zero by around or just after sunrise. Yellowstone National
Park in addition to many other mountain locations will see low
temperatures dropping to as low as 30 below zero. The lowest
temperatures will occur in places where the skies clear
completely. High temperatures tomorrow will only rise into the
single digits to lower teens. Wednesday morning lows will be
equally cold across the region...even colder in some Basin
locations. Although winds themselves will be relatively quiet,
wind chill temperatures this morning through Wednesday morning may
drop as low as 25 to 40 below zero at times.

$$


Hazardous Weather Outlook


Hazardous Weather Outlook
National Weather Service Cheyenne WY
602 AM MST Tue Feb 20 2018

WYZ101>119-211045-
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-
602 AM MST Tue Feb 20 2018

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

.DAY ONE...TODAY AND TONIGHT

A Wind Chill Advisory is in effect until 8 am today for much of
southeast Wyoming, with a Wind Chill Warning in effect until 8 am
for Arlington, Elk Mountain, the Laramie Valley and the I-80
Summit and foothills between Laramie and Cheyenne. Wind chill
temperatures in the advisory will range from 20 below to 30
degrees below zero. Wind chill temperatures will range from 30
below to 40 degrees below zero in the warning.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

The probability for widespread hazardous weather is low.

.Spotter information statement...

Spotter activation will not be needed.

$$

Hazardous Weather Outlook
National Weather Service Rapid City SD
557 AM MST Tue Feb 20 2018

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-211300-
Harding-Perkins-Butte-Northern Meade Co Plains-Ziebach-
Northern Black Hills-Northern Foot Hills-Rapid City-
Southern Foot Hills-Central Black Hills-Southern Black Hills-
Custer Co Plains-Pennington Co Plains-Haakon-Fall River-
Oglala Lakota-Jackson-Bennett-Mellette-Todd-Tripp-
Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-Northern Campbell-Southern Campbell-
Western Crook-Wyoming Black Hills-Weston-Northeastern Crook-
557 AM MST Tue Feb 20 2018 /657 AM CST Tue Feb 20 2018/

This Hazardous Weather Outlook is for western South Dakota and
northeastern Wyoming.

.DAY ONE...Today and Tonight

Wind chills of 20 below to 35 below zero are expected this
morning.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Wind chills of 20 below to 35 below zero are expected Wednesday
morning.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

$$

Hazardous Weather Outlook
National Weather Service Riverton WY
527 AM MST Tue Feb 20 2018

WYZ001>020-022>030-211230-
Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Big Horn Basin-Southwest Big Horn Basin-
Southeast Big Horn Basin-Owl Creek and Bridger Mountains-
Bighorn Mountains West-Bighorn Mountains Southeast-
Northeast Johnson County-Southeast Johnson County-
Teton and Gros Ventre Mountains-Jackson Hole-
Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
527 AM MST Tue Feb 20 2018

...Wind Chill Warning for much of Natrona County through 10 AM
this Morning...

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...Today and Tonight

Wind chills between 25 and 40 below zero are expected across the lower
elevations of Natrona County this morning. Otherwise, bitter cold
temperatures will occur. Morning low temperatures will range from
5 to 30 below zero west of the Divide...10 to 30 below zero east
of the Divide. Highs today will only range into the single digits
to lower teens.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Wednesday...Extremely cold temperatures continue. Morning low
temperatures will range from 10 to 20 below zero west of the
Divide...10 to 25 below zero east of the Divide.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report snowfall amounts. Thank you.

$$

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
447 AM MST Tue Feb 20 2018

COZ030>051-211200-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
447 AM MST Tue Feb 20 2018

...Wind Chill advisory until 8 am this morning for portions of far
Northern and Northeast plains of Colorado...

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

Very cold wind chill readings of -15 to -25 degrees below zero can
be expected through 8 am across portions of northeast Colorado and
locations near the Wyoming border. A weak disturbance will bring
areas of light snow to the mountains and the adjacent plains later
this afternoon and evening. Additional snowfall in the mountains
will be up to 2 inches, while the adjacent plains will see
amounts less than an inch. Temperatures will remain very cold
today with readings struggling into the teens.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Scattered snow showers will continue over the higher mountains
into Wednesday morning. The plains will see dry conditions through
Wednesday with temperatures staying around freezing. By Thursday
into early Friday another disturbance will bring chances for
additional snow in the mountains and a slight chance for the
plains. Conditions will dry into the weekend with temperatures
slowly rebounding back into the lower 40s.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

$$

Hazardous Weather Outlook
National Weather Service GRAND JUNCTION CO
435 AM MST Tue Feb 20 2018

COZ001>014-017>023-UTZ022>025-027>029-211145-
Lower Yampa River Basin-Central Yampa River Basin-
Roan and Tavaputs Plateaus-Elkhead and Park Mountains-
Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor-
Central Colorado River Basin-Grand and Battlement Mesas-
Gore and Elk Mountains/Central Mountain Valleys-
Central Gunnison and Uncompahgre River Basin-
West Elk and Sawatch Mountains-Flat Tops-
Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide-
Northwest San Juan Mountains-Southwest San Juan Mountains-
Paradox Valley/Lower Dolores River-
Four Corners/Upper Dolores River-Animas River Basin-
San Juan River Basin-Southeast Utah-Eastern Uinta Mountains-
Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat-
La Sal and Abajo Mountains-Canyonlands/Natural Bridges-
435 AM MST Tue Feb 20 2018

This hazardous weather outlook is for eastern Utah and western
Colorado.

.DAY ONE...Today and Tonight

Isolated to scattered snow showers will continue to today focused
on the mountain ranges but a few will venture into the valley
locations. Snow amounts should remain fairly light but impact
could include quickly dropping visibility along with a quick
dusting of snow on the roadway. Travel could be impacted at times
due to icy and snow packed roadways.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Cold conditions settle into the area tonight as skies clear.
Patchy dense valley fog may develop as a result of these clearing
skies over new snow the new snow pack. Snow re-enters the picture
late Wednesday into Thursday with the next storm system. The
southern to central Colorado mountains will be favored for heavier
snowfall. Another system then arrives late in the week into the
weekend and should bring another round of snowfall to the area.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected today or tonight, however
spotters are encouraged to report snowfall amounts to the
National Weather Service in Grand Junction.

$$

Hazardous Weather Outlook
National Weather Service North Platte NE
352 AM CST Tue Feb 20 2018

NEZ004>010-022>029-035>038-056>059-069>071-094-211000-
Sheridan-Eastern Cherry-Keya Paha-Boyd-Brown-Rock-Holt-Garden-
Grant-Hooker-Thomas-Blaine-Loup-Garfield-Wheeler-Arthur-McPherson-
Logan-Custer-Deuel-Keith-Perkins-Lincoln-Chase-Hayes-Frontier-
Western Cherry-
352 AM CST Tue Feb 20 2018 /252 AM MST Tue Feb 20 2018/

This Hazardous Weather Outlook is for portions of western and
north central Nebraska.

.DAY ONE...TODAY AND TONIGHT.

Light snow will taper off this morning with additional
accumulations of an inch or less.

The combination of subzero lows and north winds will create
dangerously cold wind chills across the northern Sandhills
tonight. The coldest wind chills are expected in Sheridan and
Cherry counties with values approaching -25.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

A quick-moving system will bring light snow to the area Thursday.
Light accumulations are possible, mainly for north central
Nebraska.

Another chance of snow exists late Friday into Saturday. Light
accumulations cannot be ruled out.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

&&

Get your weather, hydrological, and climate information at
http://www.weather.gov/northplatte

$$

U.S. Dept. of Commerce
NOAA National Weather Service
1325 East West Highway
Silver Spring, MD 20910
E-mail: w-nws.webmaster@noaa.gov
Page last modified: June 2, 2009
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