If you don't have to travel tonight or early Tuesday, don't.

And it's not just a matter of don't, because on a growing number of highways, you can't.

The winter storm clobbering central Wyoming from Montana to Colorado already has dumped several inches of snow on wet and now freezing pavement.

This is making for hazardous driving conditions,.

And as of 10:45 p.m. Monday, the Wyoming Department of Transportation has shut down Interstate 25 from Casper to Buffalo. I-25 is increasingly slick in spots south of Casper.

While I-80 remains open, WYDOT reports the highway across most of the state is beleaguered with slick spots, snowfall, blowing snow, fog, limited visibility and other rough conditions.

Likewise, I-90 between Buffalo and Sheridan is slick with snowfall, blowing snow and black ice.

The same conditions exist on U.S. Highway 26 from Afton, through Jackson, Dubois and Riverton, with one big exception: WYDOT has closed the U.S.  Highway 20-26 between Casper and Shoshoni.

WYDOT also has closed Wyoming Highway 487 from Wyoming Highway 220  through the Shirley Basin to Medicine Bow.

Medicine Bow is along U.S. Highway 30, which is closed between Walcott Junction at I-80 east to Rock River.

It advises no unnecessary travel on Wyoming Highway 220.

WYDOT cautions motorist to not travel if necessary north of Sheridan, between Shoshoni and Cody, near Powell.

The weather and road conditions are changing quickly. So before you head out, check the National Weather Service and WYDOT links above.

No unnecessary travel in the Casper area is also advised. More snowfall is expected overnight as the winter storm warning remains in effect until midnight Tuesday 12/15.

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