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Hazardous Weather Outlook


Hazardous Weather Outlook
National Weather Service Riverton WY
304 AM MDT Tue May 18 2021

WYZ001>020-022>030-190915-
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-
304 AM MDT Tue May 18 2021

This Hazardous Weather Outlook is for Western and Central Wyoming.

.DAY ONE...Today and Tonight.

Very isolated late day thunderstorms in and near the mountains.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

Wednesday...Afternoon thunderstorms possible across much of the
area, with the most numerous in the northwest.

Thursday...A good chance of thunderstorms across the northern half
of the area, some storms could be strong to severe. Strong winds
and elevated fire weather possible across southern Wyoming in the
afternoon.

Friday and Saturday...Widespread afternoon and evening
thunderstorms across the area. Some storms could be strong.


.SPOTTER INFORMATION STATEMENT...

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

$$

Hazardous Weather Outlook
National Weather Service Salt Lake City UT
418 PM MDT Tue May 18 2021

UTZ101>131-WYZ021-191300-
Great Salt Lake Desert and Mountains-Tooele and Rush Valleys-
Eastern Box Elder County-Northern Wasatch Front-Salt Lake Valley-
Utah Valley-Cache Valley/Utah Portion-Wasatch Back-
Bear Lake and Bear River Valley-Wasatch Mountains I-80 North-
Wasatch Mountains South of I-80-Western Uinta Mountains-
Wasatch Plateau/Book Cliffs-Western Uinta Basin-
Western Millard and Juab Counties-Eastern Juab/Millard Counties-
Central Mountains-Sanpete Valley-Sevier Valley-Castle Country-
San Rafael Swell-Southwest Utah-Lower Washington County-
Zion National Park-Southern Mountains-Upper Sevier River Valleys-
Bryce Canyon Country-South Central Utah-
Capitol Reef National Park and Vicinity-Western Canyonlands-
Glen Canyon Recreation Area/Lake Powell-Southwest Wyoming-
418 PM MDT Tue May 18 2021

This Hazardous Weather Outlook is for portions of central Utah...
northern Utah...southern Utah...southwest Utah and southwest
Wyoming.

.DAY ONE...Tonight

No hazardous weather is expected.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Mid level moisture will increase Wednesday across northern Utah
Wednesday resulting in a threat for high based showers and
thunderstorms capable of producing strong microburst winds.

Southwesterly winds are expected to begin to increase Wednesday
and continue through Friday which will result in hazardous fire
weather conditions across southern Utah where fuels are dry.

These winds will strengthen Thursday with windy to very windy
conditions expected across central and southern Utah. A High Wind
Watch is in effect for western Millard and Juab counties as well
as southwest Utah. These winds may cause areas of blowing dust
and choppy conditions on area waterways. There is a potential for
similar conditions to linger into at least Saturday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please relay any information
about observed severe weather to the NWS while following all
local, state, and CDC guidelines.

$$

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 Billings MT
314 PM MDT Tue May 18 2021

MTZ030>033-036-037-057-058-138-WYZ199-192115-
Treasure-Northern Rosebud-Custer-Fallon-Powder River-Carter-
Northern Big Horn-Southern Rosebud-Southern Big Horn-
Sheridan Foothills-
314 PM MDT Tue May 18 2021

This Hazardous Weather Outlook is for portions of south central
Montana...southeast Montana and north central Wyoming.

* WHAT...Potential for severe thunderstorms.

* WHERE...Southeast Montana and north central Wyoming.

* WHEN...Thursday afternoon and evening.

* ADDITIONAL DETAILS...Storms on Thursday have the potential to
  produce strong wind gusts and hail. Greatest potential for severe
  weather is east of Forsyth and Lame Deer. Stay alert if you have
  outdoor plans Thursday afternoon and evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be sure to check back for further updates on this potentially
hazardous weather.

Additional graphics can be found at:

https://www.weather.gov/billings

&&

$$

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1104 AM MDT Tue May 18 2021

COZ030>051-191715-
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-
1104 AM MDT Tue May 18 2021

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

.DAY ONE...Today and Tonight

Cool today with scattered moderate to heavy rain with isolated
thunderstorms possible through the afternoon. Storms will be
moving fairly quickly but could drop a quick one to two tenths of
rain in a short period of time. Conditions will improve after 6 pm
with mostly cloudy skies overnight and mild temperatures.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Scattered to isolated thunderstorms will be possible Wednesday and
Thursday with most of these storms over the higher terrain and far
northern Colorado. On Wednesday, there will be a limited threat
for flash flooding in the recent burn areas. On Thursday, a
couple storms may be severe over the northern border area.

There will be a better chance for thunderstorms Friday and
Saturday. Some of these storms may be strong to severe as well.


.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated today or tonight.

$$

Hazardous Weather Outlook
National Weather Service Rapid City SD
558 AM MDT Tue May 18 2021

SDZ028-029-043-044-046-047-049-191300-
Central Black Hills-Southern Black Hills-Jackson-Bennett-Mellette-
Todd-Tripp-
558 AM MDT Tue May 18 2021 /658 AM CDT Tue May 18 2021/

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

.DAY ONE...Today and Tonight

Isolated thunderstorms are possible this afternoon. Severe storms
are not expected at this time.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Chances for showers and thunderstorms will increase, especially
by late week, as an upper level system slowly moves over the
Rockies region. There is a slight risk for severe storms over much
of northeast Wyoming and far western South Dakota Thursday
afternoon and early evening, with a marginal risk elsewhere. Large
hail and strong wind gusts would be the main threats from any
severe storms. A few strong to severe storms are a possibility
on Friday as well.

.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
447 AM MDT Tue May 18 2021

COZ001>014-017>023-UTZ022>025-027>029-191100-
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-
447 AM MDT Tue May 18 2021

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

.DAY ONE...Today and Tonight

Thunderstorm development will be possible over much of the
Colorado High County and adjacent valleys today...with a few
isolated storms possible in the lower valleys. Gusty outflow
winds...and small hail will be the main threats. Snowfall is
likely to fall near pass level through the morning rising to near
treeline this afternoon. Roadways this morning could be slushy to
snowpacked over the passes...with mainly wet roads expected this
afternoon.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Afternoon thunderstorm development will be possible over portions
of the eastern Utah and western Colorado through the remainder of
the week. Critical fire weather conditions could become widespread
by Thursday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

$$

Hazardous Weather Outlook
National Weather Service Cheyenne WY
441 AM MDT Tue May 18 2021

WYZ114-191045-
Snowy Range-
441 AM MDT Tue May 18 2021

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

.DAY ONE...TODAY AND TONIGHT

A couple of brief downpours are possible over the burn scar this
afternoon and early this evening. As a result, there will be a
limited threat for flooding at this point.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

There is still a threat for a few showers and thunderstorms on
Wednesday and Thursday over the burn scar. However, once again
these showers and storms will be brief with limited flood threat.

.Spotter information statement...

Spotter activation will not be needed.


$$

Hazardous Weather Outlook
National Weather Service Cheyenne WY
441 AM MDT Tue May 18 2021

NEZ002-095-WYZ101>107-191045-
Dawes County-Northern Sioux County-
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-
441 AM MDT Tue May 18 2021

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

.DAY ONE...TODAY AND TONIGHT

A couple of isolated thunderstorms will be possible this
afternoon and early this evening. The main threat will be brief
heavy downpours and small hail.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A few isolated thunderstorms cannot be ruled out on Wednesday, but
more scattered thunderstorms are possible on Thursday. A few of
these storms may become severe on Thursday. More thunderstorms
are expected the remainder of this week.

.Spotter information statement...
Spotter activation may be needed on Thursday.

$$

Hazardous Weather Outlook
National Weather Service Cheyenne WY
441 AM MDT Tue May 18 2021

NEZ003-019>021-054-055-096-WYZ108>113-115>119-191045-
Box Butte County-Scotts Bluff County-Banner County-Morrill County-
Kimball County-Cheyenne County-Southern Sioux County-
Goshen County-Central Carbon County-North Snowy Range Foothills-
Southwest Carbon County-Sierra Madre Range-
Upper North Platte River Basin-Laramie Valley-South Laramie Range-
South Laramie Range Foothills-Central Laramie County-
East Laramie County-
441 AM MDT Tue May 18 2021

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

.DAY ONE...TODAY AND TONIGHT

A couple of isolated thunderstorms will be possible this
afternoon and early this evening. The main threat will be brief
heavy downpours and small hail.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A few isolated thunderstorms cannot be ruled out on Wednesday, but
more scattered thunderstorms are possible on Thursday. A few of
these storms may become severe on Thursday. More thunderstorms
are expected the remainder of this week.


.Spotter information statement...
Spotter activation may be needed on Thursday.

$$

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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