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Hazardous Weather Outlook


Hazardous Weather Outlook
National Weather Service Riverton WY
210 AM MDT Mon May 21 2018

WYZ001>020-022>030-221100-
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-
210 AM MDT Mon May 21 2018

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...Today and Tonight

Isolated afternoon and evening thunderstorms mainly over the
northern and western portions.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Tuesday...Widespread showers and thunderstorms by late afternoon,
continuing overnight. Heavy rain with localized flooding with the
stronger storms, especially east of the Divide. Some stronger
storms will have hail and strong wind gusts.

Wednesday...A chance of afternoon and evening thunderstorms,
especially over western and northern portions. Locally heavy rain
possible over the northwest.

Thursday...A chance of afternoon and evening thunderstorms over
and near the mountains. Isolated thunderstorms elsewhere.

Sunday...A chance of thunderstorms in the west. Isolated
thunderstorms elsewhere.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

$$

Hazardous Weather Outlook
National Weather Service Rapid City SD
619 AM MDT Mon May 21 2018

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ057-071-
221300-
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-Wyoming Black Hills-Northeastern Crook-
619 AM MDT Mon May 21 2018 /719 AM CDT Mon May 21 2018/

This Hazardous Weather Outlook is for portions of northwestern
South Dakota...south central South Dakota...southwestern South
Dakota...the Black Hills of South Dakota...northeast Wyoming...
and the Black Hills of Wyoming.

.DAY ONE...Today and Tonight

No hazardous weather expected at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Daily chances for thunderstorms can be expected for the remainder
of the week as warmer air returns to the region. The best chances
for storms will be on Tuesday and Wednesday, when there is a
marginal risk of strong to severe storms across much of the area.

.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 Rapid City SD
619 AM MDT Mon May 21 2018

WYZ054>056-058-221300-
Northern Campbell-Southern Campbell-Western Crook-Weston-
619 AM MDT Mon May 21 2018

This Hazardous Weather Outlook is for portions of northeast
Wyoming.

.DAY ONE...Today and Tonight

Isolated thunderstorms will be possible late this afternoon and
evening. Severe storms are not anticipated at this time.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Daily chances for thunderstorms can be expected for the remainder
of the week as warmer air returns to the region. The best chances
for storms will be on Tuesday and Wednesday, when there is a
marginal risk of strong to severe storms across much of the area.

.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 Grand Junction CO
533 AM MDT Mon May 21 2018

COZ001>014-017>023-UTZ022>025-027>029-221200-
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-
533 AM MDT Mon May 21 2018

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

.DAY ONE...Today and Tonight

An area of low pressure to the west will bring moisture into the
area today. Daytime heating and favorable orographics will lend
themselves to some showers and thunderstorms for the southern
valleys, San Juans and central mountains. Most convection will end
shortly after sunset.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Low pressure will continue to march eastward and as it does, bring
showers and storms Tuesday and less on Wednesday. After that, dry
conditions look to build in briefly until another low approaches
from the west.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

$$

Hazardous Weather Outlook
National Weather Service Salt Lake City UT
523 AM MDT Mon May 21 2018

UTZ001>016-019>021-517-518-WYZ021-221300-
Cache Valley/Utah Portion-Northern Wasatch Front-
Salt Lake and Tooele Valleys-Southern Wasatch Front-
Great Salt Lake Desert and Mountains-Wasatch Mountain Valleys-
Wasatch Mountains I-80 North-Wasatch Mountains South of I-80-
Western Uinta Mountains-Wasatch Plateau/Book Cliffs-
Western Uinta Basin-Castle Country-San Rafael Swell-
Sanpete/Sevier Valleys-West Central Utah-Southwest Utah-
Utahs Dixie and Zion National Park-South Central Utah-
Glen Canyon Recreation Area/Lake Powell-Central Mountains-
Southern Mountains-Southwest Wyoming-
523 AM MDT Mon May 21 2018

This Hazardous Weather Outlook is for the western two thirds of
Utah and southwest Wyoming.

.DAY ONE...Today and Tonight

Warm conditions combined with single digit RH values and gusty
southerly winds will enhance the fire weather threat across
southern Utah this afternoon.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

It will remain warm and dry with gusty winds Tuesday across
southeast Utah.

After a cooler day Tuesday, a significant warming and drying trend
is expected Wednesday through the upcoming weekend.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

$$

For more information from NOAA/s National Weather Service visit...
http://weather.gov/saltlakecity

For information on potential road travel impacts visit...
http://www.udottraffic.utah.gov/roadweatherforecast.aspx

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
506 AM MDT Mon May 21 2018

COZ030>051-221115-
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-
506 AM MDT Mon May 21 2018

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

.DAY ONE...Today and Tonight

Patchy morning fog may reduce visibility to a quarter mile through
mid morning. It will be warmer today with scattered afternoon and
evening thunderstorms, mainly over the mountains. The stronger
storms may produce brief moderate to heavy rain and small hail.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Drier and warmer weather will continue through the week. There
will be a chance of of afternoon and evening thunderstorms on
Tuesday with only a slight chance of storms Wednesday through
Friday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

$$

Hazardous Weather Outlook
National Weather Service Cheyenne WY
357 AM MDT Mon May 21 2018

NEZ002-003-019>021-054-055-095-096-WYZ101>119-221000-
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-
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-
357 AM MDT Mon May 21 2018

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

.DAY ONE...TODAY AND TONIGHT

isolated thunderstorms are possible this afternoon into early this
evening.  Severe storms are not expected.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

Widely scattered thunderstorms are possible mainly Tuesday and
Wednesday. A few strong to severe storms are possible over the
plains east of the mountains.

.Spotter information statement...

Spotter activation will not be needed.

$$

Hazardous Weather Outlook
National Weather Service Billings MT
327 AM MDT Mon May 21 2018

MTZ030>033-036-037-058-220930-
Treasure-Northern Rosebud-Custer-Fallon-Powder River-Carter-
Southern Rosebud-
327 AM MDT Mon May 21 2018

This Hazardous Weather Outlook is for portions of southeast
Montana.

* WHAT...Showers and thunderstorms, with potential for heavy
  rainfall and a few severe storms.

* WHERE...Across southeast Montana.

* WHEN...Tuesday afternoon through Wednesday.

* ADDITIONAL DETAILS...A few severe thunderstorms capable of
  producing large hail and strong winds are possible Tuesday
  afternoon and evening.

* ADDITIONAL HAZARD CONCERNS...Showers and thunderstorms will
  likely produce areas of heavy rainfall Tuesday afternoon through
  Wednesday. Some rivers and streams could see rises from this
  rainfall.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Hazardous Weather Outlook is issued when hazardous weather could
impact the region within the next week. Be sure to stay tuned for
future updates as locations, timing, and impacts could change.
Begin preparations to mitigate any impacts that could result from
the hazardous weather.

&&

$$

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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