Troopers in Tennessee are fanning out for welfare checks on those who haven’t been heard from in days. It could be days before power is restored across the South, where more subfreezing temperatures are expected by Friday in areas unaccustomed to and ill-equipped for such cold. The situation in northern Mississippi was “life-or-death,” said Jamie Parttridge, a longtime resident of Batesville, along icy Interstate 55 in the hard-hit northern part of the state. Nancy Dillon, 87, spent three days without power on her family farm in the rural outskirts of Nashville, relying on her fireplace for warmth. Around 90,000 outages remained in Nashville, Tennessee, where downed trees and snapped power lines blocked access to some areas.