WASHINGTON (AP) — Meteorologists warn that a stretched polar vortex could bring severe winter weather to much of the United States. This week, warm Arctic waters and cold continental land are combining to send subzero temperatures, heavy snow, and ice across the eastern two-thirds of the country. The frigid conditions are expected to persist through January and into early February. Experts say the atmospheric pattern is set, with the potential for crippling ice and snow. The National Weather Service cautions about power outages and treacherous travel conditions. The Midwest and North could see temperatures as low as 30 degrees below zero. (Photo: AP)