* WHAT...Very cold wind chills as low as 25 below zero.

* WHERE...Portions of northern Indiana, southwest Michigan, and northwest Ohio.

* WHEN...Until 10 AM EST /9 AM CST/ Wednesday.

* IMPACTS...The dangerously cold wind chills as low as 25 below zero could cause frostbite on exposed skin in as little as 30 minutes. Frostbite and hypothermia will occur if unprotected skin is exposed to these temperatures. Wind chill values can lead to hypothermia with prolonged exposure.