The National Weather Service has issued a Cold Weather Advisory for all of northern Illinois as very cold conditions return Monday morning, with wind chills falling into the 15 to 25 below range.

The advisory is in effect until noon on Monday.

But cold conditions are expected to persist through the workweek with sub-zero wind chills primarily during the nighttime and morning hours, the weather service said.

Temperatures will remain in the teens for most of the week.