* WHAT...Dangerously cold wind chills around 30 below zero.
* WHERE...Dallas, Jasper, Polk, and Poweshiek Counties.
* WHEN...Until noon CST Tuesday.
* IMPACTS...The dangerously cold wind chills could cause frostbite on exposed skin in as little as 10 minutes.
* ADDITIONAL DETAILS...Wind chill values will rise quickly late Tuesday morning and by afternoon wind chills of 5 to 15 below zero will be common.