Deep freeze grips Upper Midwest, more bitter cold to come

MINNEAPOLIS (AP) — An arctic wave has wrapped parts of the Midwest in numbing cold, sending temperatures plunging and prompting officials to close dozens of schools Friday, but forecasters say the worst may be yet to come.Cold weather advisories were in effect from North Dakota to Ohio, with dangerously cold wind chills that could dip to as low as 45 below zero in northern Wisconsin and Minnesota and to 35 below in parts of northern Illinois and Iowa.The bitter cold caused administrators i