Much of southeast Wyoming is under a Winter Storm Warning this morning as an unusually early winter storm system continues its track across the northern Rocky Mountains and into the Great Plains.

The Cheyenne Office of the National Weather Service issued this statement at 3:45 a.m.:

Many of you will wake up to no snow on the ground…yet. Instead of rain changing to snow quickly as originally expected, significant accretion of ice from freezing drizzle has accumulated on surfaces overnight. This has happened due to the coldest air temperatures aloft not arriving as quickly as expected. Some areas have already had over 1/8 of an inch of ice accumulation on elevated surfaces. This may result in potential power outages. More winter weather is on the way for southeast Wyoming and the Nebraska Panhandle as the headlines are out through Wednesday morning. Expect impacts to travel at the highest elevations due to moderate/heavy snow due to reduced visibility and slick roads. Stay tuned for more information on the weather event.

Hazards: Heavy snow accumulations are still possible. Lingering warm surfaces will lead to the first snow to melt on impact. We expect the Wyoming High Plains getting 3 to 6 inches combined with significant ice accretion potentially over ¼ inch, 0 to 2 inches across the Panhandle at elevations below 4000 feet, and higher amounts of 6 to 12 inches across the mountains, with localized higher amounts at the highest elevations in the mountain zones above 9500 feet. Snowfall totals are based off melted liquid equivalents