Winter Weather Warnings / Watches / Advisories
Issued by NWS Riverton, WY

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WWUS45 KRIW 171755
WSWRIW

URGENT - WINTER WEATHER MESSAGE
National Weather Service Riverton WY
1155 AM MDT Sun May 17 2026

WYZ018-181300-
/O.UPG.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
/O.EXA.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
Lander Foothills-
Including the cities of Lander
1155 AM MDT Sun May 17 2026

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

* WHAT...Snow expected. Total snow accumulations between 5 and 8
  inches, with higher amounts near Sinks Canyon Park.

* WHERE...Lander Foothills.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult. The hazardous conditions
  could impact the Monday morning commute. Heavy snow could break
  tree limbs as many trees have leafed out.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ015-181300-
/O.CON.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
Wind River Mountains East-
1155 AM MDT Sun May 17 2026

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

* WHAT...Heavy snow expected. Total snow accumulations between 9 and
  18 inches, with locally higher amounts at the highest elevations.
  Winds gusting as high as 60 mph.

* WHERE...Wind River Mountains East.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be very difficult. The hazardous conditions
  could impact the Monday morning commute, including over South Pass.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ019-181300-
/O.CON.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
Green Mountains and Rattlesnake Range-
Including the cities of Jeffrey City
1155 AM MDT Sun May 17 2026

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

* WHAT...Heavy snow possible. Total snow accumulations between 7 and
  12 inches possible with locally higher amounts up to 15 inches.
  Winds gusting as high as 55 mph.

* WHERE...Green Mountains and Rattlesnake Range.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel will be difficult. The hazardous conditions will
  impact the Monday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ020-181300-
/O.CON.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
Natrona County Lower Elevations-
Including the cities of Casper
1155 AM MDT Sun May 17 2026

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

* WHAT...Heavy snow expected. Total snow accumulations between 3 and
  6 inches. Areas of higher amounts up to 8 inches between Hiland
  and Casper. Winds gusting as high as 40 mph.

* WHERE...Natrona County Lower Elevations.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel will be difficult, especially along Highway 20/26
  between Hiland and Casper. The hazardous conditions will impact
  the Monday morning commute. Heavy snow could break tree limbs as
  many trees have leafed out.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ022-181300-
/O.CON.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
Casper Mountain-
1155 AM MDT Sun May 17 2026

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

* WHAT...Heavy snow possible. Total snow accumulations between 10
  and 18 inches possible. Winds could gust as high as 40 mph.

* WHERE...Casper Mountain.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be very difficult. Areas of blowing snow
  could significantly reduce visibility. The hazardous conditions
  could impact the Monday morning commute. Heavy snow could break
  tree limbs as many trees have leafed out.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ030-181300-
/O.CON.KRIW.WS.W.0005.260518T0000Z-260519T0000Z/
East Sweetwater County-
Including the cities of Wamsutter
1155 AM MDT Sun May 17 2026

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

* WHAT...Heavy snow expected. Total snow accumulations between 7 and
  10 inches. Winds gusting as high as 60 mph.

* WHERE...East Sweetwater County.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel will be very difficult, especially along
  Interstate 80. The hazardous conditions will impact the Monday
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in
your vehicle in case of an emergency.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ002-007>009-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Absaroka Mountains-Owl Creek and Bridger Mountains-Bighorn
Mountains West-Bighorn Mountains Southeast-
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations between 4 and 8
  inches, with 7 to 12 inches at the highest elevations of the
  southern Absaroka and southern Bighorn Mountains. Winds gusting as
  high as 50 mph.

* WHERE...Owl Creek and Bridger Mountains, Bighorn Mountains
  Southeast, Bighorn Mountains West, and Absaroka Mountains.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult, especially over mountain
  passes such as Powder River Pass.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ003-005-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Cody Foothills-Southwest Bighorn Basin-
Including the cities of Clark, Meeteetse, Cody, and Thermopolis
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations up to 2 inches.
  Winds gusting as high as 50 mph.

* WHERE...Southwest Bighorn Basin and Cody Foothills.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult due to a combination of snow
  and wind. The hazardous conditions could impact the Monday morning
  commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ010-011-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Northeast Johnson County-Southeast Johnson County-
Including the cities of Buffalo and Kaycee
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations up to 2 inches.
  Winds gusting as high as 50 mph.

* WHERE...Northeast Johnson County and Southeast Johnson County.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult due to a combination of wind
  and blowing snow. The hazardous conditions could impact the Monday
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ014-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Wind River Mountains West-
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations between 4 and 8
  inches. Winds gusting as high as 50 mph.

* WHERE...Wind River Mountains West.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult, especially along South Pass.
  The hazardous conditions could impact the Monday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ016-017-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Upper Wind River Basin-Wind River Basin-
Including the cities of Dubois, Shoshoni, and Riverton
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations between 1 and 4
  inches, with locally higher amounts are possible around Hudson and
  Fort Washakie. Winds gusting as high as 45 mph.

* WHERE...Upper Wind River Basin and Wind River Basin.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult due to a combination of snow
  and wind. The hazardous conditions could impact the Monday morning
  commute. Where heavy snow occurs, it is possible for tree limbs to
  break, as many trees have leafed out.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ026-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Upper Green River Basin-
Including the cities of Farson, La Barge, and Big Piney
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations 1 to 3 inches.
  Winds gusting as high as 45 mph.

* WHERE...Upper Green River Basin.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult due to a combination of wind
  and falling snow. The hazardous conditions could impact the Monday
  morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ027-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
South Lincoln County-
Including the cities of Cokeville and Kemmerer
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations between 3 and 5
  inches. Winds gusting as high as 40 mph.

* WHERE...South Lincoln County.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult. The hazardous conditions
  could impact the Monday morning commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

WYZ028-029-181300-
/O.CON.KRIW.WW.Y.0019.260518T0000Z-260519T0000Z/
Rock Springs and Green River-Flaming Gorge-
Including the cities of Green River and Rock Springs
1155 AM MDT Sun May 17 2026

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING
TO 6 PM MDT MONDAY...

* WHAT...Snow expected. Total snow accumulations between 2 and 5
  inches. Winds gusting as high as 55 mph.

* WHERE...Flaming Gorge and Rock Springs and Green River.

* WHEN...From 6 PM this evening to 6 PM MDT Monday.

* IMPACTS...Travel could be difficult, especially along Interstate
  80. The hazardous conditions could impact the Monday morning
  commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling.

For graphical depictions of the snowfall forecast, including the
official NWS forecast, high end amounts, and low end amounts, visit
https://weather.gov/riw/winter .

For winter road conditions from the Wyoming Department of
Transportation, visit https://wyoroad.info .

&&

$$

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

Wittmann