DECATUR, Ill. (WAND) - A Christmas inversion is probably something that you didn't want to hear.

Nonetheless, here we are.

You may even ask yourself, if an inversion is when warm air aloft resides over cool air at the ground, when is it getting cool? The short answer is not until later this weekend/early next week. 

CLICK HERE for Jim Kosek's Christmas Day forecast.

So, what gives?

Well, the mild air at the ground is still trapped under an inversion. A better way to say it may be warm air at the ground underneath, even warmer air above our heads.   

Inversions trap everything: pollutants, moisture in the form of clouds and fog, but also our latest dose of mild weather. 

A Dense Fog Advisory is in place for most of central Illinois until 10 a.m. Christmas morning. The National Weather Service visibility in some areas to drop to a quarter-mile or less. 

Fog could make driving conditions hazardous so allow extra time if you are traveling. 

While it is warm the rest of this holiday week, you will need to allow extra time to get to your destination due to the blanket of fog.

Good thing Santa has Rudolph. Christmas is on!

Happy Holidays!

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