Wind Chill will be -20 to -25 early this morning. Exposure of skin for 30 minutes to this bitter cold will result in frostbite. Dress Warm!— NWS Northern Indiana (@NWSIWX) January 24, 2014 URGENT - WINTER WEATHER MESSAGENATIONAL WEATHER SERVICE NORTHERN INDIANA336 AM EST FRI JAN 24 2014.AN ARCTIC AI