WWUS45 KRIW 151756 WSWRIW URGENT - WINTER WEATHER MESSAGE National Weather Service Riverton WY 1156 AM MDT Wed Apr 15 2026 WYZ001-002-012-161300- /O.CON.KRIW.WS.W.0004.260416T0000Z-260417T1200Z/ Yellowstone National Park-Absaroka Mountains-Teton and Gros Ventre Mountains- Including the cities of Lake, Mammoth, and Old Faithful 1156 AM MDT Wed Apr 15 2026 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING TO 6 AM MDT FRIDAY... * WHAT...Heavy snow expected. Total snow accumulations between 9 and 18 inches, with the highest elevations could see up to 20 inches. Winds gusting between 30 and 50 mph. Higher elevations could gust up to 55 mph. * WHERE...Absaroka Mountains, Teton and Gros Ventre Mountains, and Yellowstone National Park. * WHEN...From 6 PM this evening to 6 AM MDT Friday. * IMPACTS...Travel could be very difficult, especially across Teton Pass and Togwotee Pass. Strong winds will cause limited visibility. 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 . && $$ WYZ014-015-161300- /O.CON.KRIW.WS.W.0004.260416T0000Z-260418T0000Z/ Wind River Mountains West-Wind River Mountains East- 1156 AM MDT Wed Apr 15 2026 ...WINTER STORM WARNING REMAINS IN EFFECT FROM 6 PM THIS EVENING TO 6 PM MDT FRIDAY... * WHAT...Heavy snow expected. Total snow accumulations between 9 and 18 inches across the mountains. Expect snow accumulations of 5 to 7 inches for South Pass. Winds gusting between 45 and 60 mph, including across South Pass. * WHERE...Wind River Mountains East and Wind River Mountains West. * WHEN...From 6 PM this evening to 6 PM MDT Friday. * IMPACTS...Travel could be very difficult, especially across South Pass. Strong winds will cause limited visibility. PRECAUTIONARY/PREPAREDNESS ACTIONS... If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. For graphical depictions of the snowfall forecast, including the official NWS forecast, high end amounts, and low end amounts, visit https://weather.gov/riw/winter . For winter road conditions from the Wyoming Department of Transportation, visit https://wyoroad.info . && $$ WYZ008-009-161300- /O.NEW.KRIW.WW.Y.0015.260416T1500Z-260417T1200Z/ Bighorn Mountains West-Bighorn Mountains Southeast- 1156 AM MDT Wed Apr 15 2026 ...WINTER WEATHER ADVISORY IN EFFECT FROM 9 AM THURSDAY TO 6 AM MDT FRIDAY... * WHAT...Snow and wind expected. Total snow accumulations between 6 and 13 inches for elevations above 7,000 feet. Total snow accumulations of 9 to 12 inches across Powder River Pass. Winds gusting between 35 and 55 mph. * WHERE...Bighorn Mountains Southeast and Bighorn Mountains West. * WHEN...From 9 AM Thursday to 6 AM MDT Friday. * IMPACTS...Travel could be difficult, especially over Powder River Pass, on Thursday. Gusty winds will cause limited visibility. 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 . && $$ WYZ010-011-161300- /O.NEW.KRIW.WW.Y.0015.260416T1800Z-260417T1200Z/ Northeast Johnson County-Southeast Johnson County- Including the cities of Kaycee and Buffalo 1156 AM MDT Wed Apr 15 2026 ...WINTER WEATHER ADVISORY IN EFFECT FROM NOON THURSDAY TO 6 AM MDT FRIDAY... * WHAT...Snow, wind, and cold expected. Total snow accumulations between 1 and 3 inches with gusty north winds. Winds gusting between 35 and 55 mph, with gusts of 60 mph possible. Expect temperatures below 28 degrees Friday morning. * WHERE...Northeast Johnson County and Southeast Johnson County. * WHEN...From noon Thursday to 6 AM MDT Friday. * IMPACTS...Plan on hazardous road conditions, including along I-25. Gusty winds and snow will cause limited visibility. Vulnerable outdoor equipment and vegetation could be impacted by freezing temperatures. * ADDITIONAL DETAILS...Snow squalls are possible Thursday afternoon and evening. If a snow squall does occur, expect instances of very low visibilities. Temperatures will drop below 28 degrees by Friday morning. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. For graphical depictions of the snowfall forecast, including the official NWS forecast, high end amounts, and low end amounts, visit https://weather.gov/riw/winter . For winter road conditions from the Wyoming Department of Transportation, visit https://wyoroad.info . && $$ WYZ016>018-161300- /O.NEW.KRIW.WW.Y.0015.260416T2100Z-260417T1200Z/ Upper Wind River Basin-Wind River Basin-Lander Foothills- Including the cities of Lander, Shoshoni, Riverton, and Dubois 1156 AM MDT Wed Apr 15 2026 ...WINTER WEATHER ADVISORY IN EFFECT FROM 3 PM THURSDAY TO 6 AM MDT FRIDAY... * WHAT...Snow, wind, and cold expected. Total snow accumulations of 0.5 to 3 inches, with isolated amounts up to 5 inches possible in the Lander Foothills. Winds gusting between 35 and 45 mph, with occasional gusts around 50 mph possible. Expect temperatures below 28 degrees Friday morning. * WHERE...Lander Foothills, Upper Wind River Basin, and Wind River Basin. * WHEN...From 3 PM Thursday to 6 AM MDT Friday. * IMPACTS...Plan on slippery and potentially hazardous road conditions, especially on US 20/26 from Shoshoni to the Fremont/Natrona County line. The hazardous conditions could impact travel on Thursday evening. Gusty winds and snow will cause limited visibility. Vulnerable outdoor equipment and vegetation could be impacted by freezing temperatures. * ADDITIONAL DETAILS...Brief periods of heavy snow bands and strong winds are possible Thursday evening, especially on US 20/26 from Shoshoni to the Fremont/Natrona County line. If a heavy band of snow does occur, expect instances of very low visibilities. Temperatures will drop below 28 degrees by Friday morning. 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 . && $$ WYZ019-022-161300- /O.NEW.KRIW.WW.Y.0015.260416T2100Z-260417T1800Z/ Green Mountains and Rattlesnake Range-Casper Mountain- Including the cities of Jeffrey City 1156 AM MDT Wed Apr 15 2026 ...WINTER WEATHER ADVISORY IN EFFECT FROM 3 PM THURSDAY TO NOON MDT FRIDAY... * WHAT...Snow and wind expected. Total snow accumulations between 3 and 8 inches, with localized higher amounts possible across the highest terrain. Winds gusting between 35 and 55 mph. * WHERE...Casper Mountain and Green Mountains and Rattlesnake Range. * WHEN...From 3 PM Thursday to noon MDT Friday. * IMPACTS...Travel could be difficult, especially across US 287. The hazardous conditions could impact travel Thursday evening through Friday morning. Gusty winds and snow will cause limited visibility. * ADDITIONAL DETAILS...Heavy snow bands and strong winds are possible Thursday evening through Friday morning. If a heavy band of snow does occur, expect instances of very low visibilities. PRECAUTIONARY/PREPAREDNESS ACTIONS... Slow down and use caution while traveling. For graphical depictions of the snowfall forecast, including the official NWS forecast, high end amounts, and low end amounts, visit https://weather.gov/riw/winter . For winter road conditions from the Wyoming Department of Transportation, visit https://wyoroad.info . && $$ WYZ020-161300- /O.NEW.KRIW.WW.Y.0015.260416T2100Z-260417T1800Z/ Natrona County Lower Elevations- Including the cities of Casper 1156 AM MDT Wed Apr 15 2026 ...WINTER WEATHER ADVISORY IN EFFECT FROM 3 PM THURSDAY TO NOON MDT FRIDAY... * WHAT...Snow, wind, and cold expected. Total snow accumulations between 2 and 5 inches, with localized amounts up to 6 inches possible. Winds gusting between 45 and 55 mph. Expect temperatures below 28 degrees Friday morning. * WHERE...Natrona County Lower Elevations. * WHEN...From 3 PM Thursday to noon MDT Friday. * IMPACTS...Plan on hazardous road conditions, including along US 20/26 from the Fremont/Natrona County line and east. Gusty winds and snow will cause limited visibility. Vulnerable outdoor equipment and vegetation could be impacted by freezing temperatures. * ADDITIONAL DETAILS...Snow squalls are possible Thursday afternoon and evening. If a snow squall does occur, expect instances of very low visibilities. Temperatures will drop below 28 degrees by Friday morning. 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/ . Gerhardt