* WHAT...Very cold wind chills as low as 30 below, with the coldest wind chills occurring during the morning and overnight hours.

* WHERE...Portions of east central, south central, and southeast Wisconsin.

* WHEN...Until noon CST Tuesday.

* IMPACTS...The dangerously cold wind chills as low as 30 below zero could cause frostbite on exposed skin in as little as 30 minutes.