Arctic blast leads to warnings about hypothermia, frostbite

PORTLAND, Maine -- As a deep freeze sets in across half the country, officials are urging people to help those most vulnerable, especially the homeless and the elderly.Forecasters warned people to be wary of hypothermia and frostbite from the arctic blast that's gripping a large swath from the Midwest to the Northeast, where the temperature, without the wind chill factored in, dipped to minus 32 Thursday morning in Watertown, New York.The prolonged, dangerous cold weather has sent advocates for