A slow-moving low pressure system and cold, Canadian air will move into the state of Wyoming today and will remained settled over the region through the end of the weekend.  We will see cloudy to mostly cloudy skies, early fog, and significantly colder temperatures statewide today.  Daytime highs will be in the 30's and 40's, with some 50's in the far eastern plains.  Heavy rain and thunderstorms will be likely across lower elevations today.  Watch out for some areas of standing water on roadways.  Light to moderate snowfall will also be possible in the mountains and higher elevations, including parts of I-80 (Elk Mountain and the Summit).  Roads will remain slick and slushy for areas receiving snow and visibility could also be reduced at times.  Heavy rain and a few thunderstorms will continue to be likely for lower elevations tonight, while snow showers will be increasing across the mountains and higher elevations. Expect reduced visibility with slick and icy roadways along I-80 (Cheyenne to Rawlins and also near Evanston), WY-28 near South Pass, and WY-220 (Muddy Gap to Casper).

Light to moderate snowfall is expected throughout the day for higher elevations on Saturday. Rain will also begin to mix with snow across lower elevations early on Saturday morning. Wet snow will then develop for lower elevations of northeastern Wyoming by noon, central Wyoming after 4 PM, and then the rest of southern Wyoming after 6 PM. Moderate to heavy snow will be likely across central and eastern Wyoming Saturday night into Sunday evening.  Expect poor visibility, blowing and drifting snow, strong winds, and hazardous driving conditions throughout these areas during this time.  Snow accumulations will range from 4-10".  Expect smaller amounts (3-6") for the rest of Wyoming, but reduced visibility and slick, icy road conditions will still be expected.  Temperatures will also be cold and well below normal statewide this weekend, with daytime highs in the 30's to lower 40's.