Special Weather Statement National Weather Service Riverton WY 649 AM MDT Mon Sep 7 2020 Yellowstone National Park-Teton and Gros Ventre Mountains- Jackson Hole-Wind River Mountains West-Star Valley- Upper Green River Basin Foothills-Upper Green River Basin- Including the cities of Lake, Mammoth, Old Faithful, Jackson, Afton, Alpine, Star Valley Ranch, Thayne, Pinedale, La Barge, Big Piney, and Farson 649 AM MDT Mon Sep 7 2020 ...Major Change to Colder Temperatures with some Snow Monday and Monday Night... This is a special weather statement from the National Weather Service Office in Riverton. * WHAT...A very strong cold front will pull south into northwest areas today and move southward across the entire area this evening, ushering in much colder temperatures. Overall snowfall amounts will be light, generally a trace to 2 inches even in the mountains. * WHERE...Far western Wyoming. * WHEN...This afternoon through Tuesday Morning. * ADDITIONAL DETAILS...People recreating on this holiday weekend need to be prepared for a sudden change to cold and wet conditions. Strong gusty winds will be possible tonight.