* WHAT...Dangerously cold wind chills between 15 and 25 below zero possible.

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

* WHEN...From late Sunday night through Wednesday morning.

* IMPACTS...The dangerously cold wind chills as low as 20 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.

* ADDITIONAL DETAILS...A period Monday into Monday night will be able to warm into the single digits below zero which provides additional uncertainty around wind chill magnitude. Time duration of this relatively warm period and individual alignment of wind and temperatures during the watch period are still uncertain. Lake effect snow and accompanying cloud cover will also impact wind chills during this time period insulating them like a blanket and keeping those areas relatively warm.