AccuWeather.com reports a surge of warm, moist air will lead to fog problems from the Midwest to the Atlantic Seaboard during the New Year's weekend.
Any time you have warm, moist air moving over a cold surface, with or without snow cover, there is the risk of fog formation.
The key is to have the air moist enough in the first place to make it easier for the fog to form.
Ideal fog conditions appear to be setting up as a zone of rain and warm air build over the Midwest and push to the Atlantic coast.
Fog is not a serious problem until the visibility drops below 1/2 mile.
However, the visibility could go much lower than that during New Year's Eve over portions of the Tennessee and Ohio valleys into the Great Lakes. Midwest cities that could end up in pea soup include Detroit, Cincinnati, Indianapolis, Nashville and perhaps Chicago.
Dense fog may also begin to reach into parts of the central and southern Appalachians and the Pittsburgh and Atlanta areas.
Any fog New Year's Eve along the East Coast is likely to be localized. The worst conditions are likely later New Year's Day and Saturday night along the Atlantic Seaboard including the cities of Boston, New York and Philadelphia.
People heading out or home from holiday adventures may run into some difficulty as a result. Fog has been known to keep aircraft on the ground or prevent them from landing.
Be prepared for such delays Friday in the Midwest and Saturday into Saturday night along the East Coast.
By the way, the blizzard hitting the northern Plains Friday night will not head to the East. However, a push of somewhat colder air will follow the weekend rain, fog and warm-up.
Enough wind and dry air from the west should rout the fog from much of the Midwest on New Year's Day and then the Atlantic Seaboard during the day Sunday.
So as the saying goes by AccuWeather colleague and Chief Meteorologist Elliot Abrams, "Once the fog is gone, it won't be mist (missed)."