There is a Dense Fog Advisory in effect along the Interstate 25 corridor from south of Denver to Wyoming until 9 a.m.
Visibility is 100 yards or less in spots, according to the National Weather Service in Boulder.
The conditions are causing slick spots along I-25 especially to the north, 7NEWS traffic anchor Jayson Luber warned.
"Dense Fog at Denver's International Airport early this morning. Check ahead with your airline about possible delays," the NWS Boulder tweeted. https://twitter.com/NWSBoulder
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