Special Weather Statement
Special Weather Statement
National Weather Service Riverton WY
307 AM MST Thu Nov 20 2025
WYZ013-017>020-023-025>028-201700-
Jackson Hole-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Star Valley-
Upper Green River Basin Foothills-Upper Green River Basin-
South Lincoln County-Rock Springs and Green River-
Including the cities of Jackson, Riverton, Shoshoni, Lander,
Jeffrey City, Casper, Afton, Alpine, Star Valley Ranch, Thayne,
Pinedale, La Barge, Big Piney, Farson, Kemmerer, Cokeville,
Rock Springs, and Green River
307 AM MST Thu Nov 20 2025
...PATCHY AREAS OF FOG THIS MORNING ACROSS PORTIONS OF WESTERN,
SOUTHERN, AND CENTRAL WYOMING...
Clearing skies and ample moisture have led to the development of
patchy areas of fog across portions of the state this morning.
Visibilities of less than one mile have already been observed
along US 20/26 from Casper to Hiland. Other locations such as Star
Valley have seen fog develop, leading to reduced visibilities of
less than one mile as well.
* WHAT...Patchy areas of fog leading to decreased visibilities of
less than one mile.
* WHERE...Portions of Western, Southern, and Central WY. Locations
such as Star Valley, Jackson Hole, Green River Basin, Wind River
Basin, and Natrona County.
* WHEN...Through 10 AM Thursday.
* ADDITIONAL DETAILS... If needing to drive through these areas
this morning, allow extra time for your commute and be prepared
for sudden drops in visibility. Slow down, use low beam
headlights, and leave extra space between you and other
motorists.
$$
Special Weather Statement
National Weather Service Sioux Falls SD
225 AM CST Thu Nov 20 2025
IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ039-040-050-054>056-059>071-201200-
Lyon-Osceola-Dickinson-Sioux-O`Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson-
Pipestone-Rock-Dixon-Dakota-Kingsbury-Brookings-Gregory-Miner-
Lake-Moody-Davison-Hanson-McCook-Minnehaha-Charles Mix-Douglas-
Hutchinson-Turner-Bon Homme-Yankton-Union-
Including the cities of Rock Rapids, George, Inwood, Larchwood,
Sibley, Spirit Lake, Milford, Arnolds Park, Sioux Center,
Orange City, Rock Valley, Hawarden, Hull, Sheldon, Hartley,
Sanborn, Spencer, Le Mars, Cherokee, Storm Lake, Sioux City,
Ida Grove, Holstein, Battle Creek, Tyler, Hendricks, Lake Benton,
Ivanhoe, Marshall, Slayton, Fulda, Windom, Mountain Lake,
Worthington, Jackson, Lakefield, Pipestone, Luverne, Wakefield,
Ponca, Allen, South Sioux City, De Smet, Arlington, Lake Preston,
Brookings, Gregory, Burke, Howard, Madison, Orland, Flandreau,
Mitchell, Alexandria, Emery, Salem, Canistota, Bridgewater,
Montrose, Sioux Falls, Wagner, Platte, Lake Andes, Marty, Armour,
Corsica, Delmont, Parkston, Freeman, Menno, Tripp, Clayton,
Parker, Centerville, Marion, Viborg, Irene, Hurley, Chancellor,
Canton, Lennox, Tea, Harrisburg, Tyndall, Scotland, Springfield,
Avon, Tabor, Yankton, Vermillion, North Sioux City, Beresford,
Elk Point, Alcester, and Jefferson
225 AM CST Thu Nov 20 2025
...AREAS OF FOG EARLY THIS MORNING...
Areas of fog occasionally reducing visibility to less than a mile
have developed early this morning. Locally dense fog will reduce
visibility to a quarter mile or less at times.
Conditions are expected to improve from northwest to southeast
through mid-morning.
Travelers should be prepared for rapidly changing visibility, and
use extra caution at intersections and railroad crossings.
$$
Hazardous Weather Outlook
Hazardous Weather Outlook
National Weather Service Sioux Falls SD
429 AM CST Thu Nov 20 2025
IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-211030-
Lyon-Osceola-Dickinson-Sioux-O`Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson-
Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Gregory-
Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-McCook-
Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-Yankton-
Union-
429 AM CST Thu Nov 20 2025
This Hazardous Weather Outlook is for northwest Iowa, west central
Iowa, southwest Minnesota, northeast Nebraska, central South
Dakota, east central South Dakota, south central South Dakota and
southeast South Dakota.
.DAY ONE...Today and tonight.
Areas of dense fog across portions of the Tri-State area are
expected to improve from northwest to southeast through mid-morning.
However, motorists should be prepared for changing visibility, as
low as a quarter mile or less at times, into the morning commute.
.DAYS TWO THROUGH SEVEN...Friday through Wednesday.
No hazardous weather is expected at this time.
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected at this time.
$$
Hazardous Weather Outlook
National Weather Service Riverton WY
314 AM MST Thu Nov 20 2025
WYZ001>020-022>030-211415-
Yellowstone National Park-Absaroka Mountains-Cody Foothills-
North Bighorn Basin-Southwest Bighorn Basin-Southeast Bighorn Basin-
Owl Creek and Bridger Mountains-Bighorn Mountains West-
Bighorn Mountains Southeast-Northeast Johnson County-
Southeast Johnson County-Teton and Gros Ventre Mountains-
Jackson Hole-Wind River Mountains West-Wind River Mountains East-
Upper Wind River Basin-Wind River Basin-Lander Foothills-
Green Mountains and Rattlesnake Range-
Natrona County Lower Elevations-Casper Mountain-Star Valley-
Salt River and Wyoming Ranges-Upper Green River Basin Foothills-
Upper Green River Basin-South Lincoln County-
Rock Springs and Green River-Flaming Gorge-East Sweetwater County-
314 AM MST Thu Nov 20 2025
...Special Weather Statement Due to Patchy Areas of Fog Has Been
Posted for Portions of Western, Southern, and Central WY to 10 AM
Thursday...
This Hazardous Weather Outlook is for Western and Central Wyoming.
.DAY ONE...Today and tonight.
Patchy areas of fog with visibilities less than one mile have begun
to develop across portions of western, southern, and central WY this
morning. Fog will likely linger through the morning gradually
dissipating by the late morning hours. Isolated showers will be
possible this morning mainly over western and southern WY.
.DAYS TWO THROUGH SEVEN...Friday through Wednesday.
Friday... Near seasonable temperatures with scattered showers
possible across portions of western and southern WY.
.SPOTTER INFORMATION STATEMENT...
Weather spotters are encouraged to report significant weather
conditions according to Standard Operating Procedures.
$$
Hazardous Weather Outlook
National Weather Service North Platte NE
407 AM CST Thu Nov 20 2025
NEZ004>010-022>029-035>038-056>059-069>071-094-211015-
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-
407 AM CST Thu Nov 20 2025 /307 AM MST Thu Nov 20 2025/
This Hazardous Weather Outlook is for portions of western and north
central Nebraska.
.DAY ONE...Today and tonight.
Patchy dense fog will persist across much of western and north
central Nebraska through late this morning.
.DAYS TWO THROUGH SEVEN...Friday through Wednesday.
No hazardous weather is expected at this time.
.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected at this time.
$$
Hazardous Weather Outlook
National Weather Service Cheyenne WY
301 AM MST Thu Nov 20 2025
NEZ002-003-019>021-054-055-095-096-WYZ101>119-211015-
Dawes County-Box Butte County-Scotts Bluff County-Banner County-
Morrill County-Kimball County-Cheyenne County-
Northern Sioux County-Southern Sioux County-
Converse County Lower Elevations-Niobrara County-
North Laramie Range-Ferris/Seminoe/Shirley Mountains-
Shirley Basin-Central Laramie Range and Southwest Platte County-
East Platte County-Goshen County-Central Carbon County-
North Snowy Range Foothills-Southwest Carbon County-
Sierra Madre Range-Upper North Platte River Basin-Snowy Range-
Laramie Valley-South Laramie Range-South Laramie Range Foothills-
Central Laramie County-East Laramie County-
301 AM MST Thu Nov 20 2025
This hazardous weather outlook is for portions of panhandle
Nebraska...east central Wyoming...south central Wyoming and
southeast Wyoming.
.DAY ONE...TODAY AND TONIGHT
Model disagreement and variability remains high for the up-coming
system tonight into early Friday morning. Lighter snow accumulations
possible along I-80, while higher amounts possible in the mountains.
.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY
First real shot of cold air could arrive as early as Tuesday, with
high temperatures possibly in the 20s and 30s Tuesday, Wednesday,
and Thursday.
.Spotter information statement...
Spotter activation will not be needed.
$$
