MEMPHIS, Tenn. - A late fall cold snap that has gripped much of the country is being blamed for a handful of deaths and has forced people to deal with frigid temperatures, power outages by the thousands, and treacherous roads.

Weather forecasters say the powerful weather system has Virginia and the Mid-Atlantic in its icy sights.

Temperatures in Montana and South Dakota were more than 20 degrees below zero during the day Saturday while much of the Midwest was in the teens and single digits. Wind chill readings could drop as low as 50 below zero in northwestern Minnesota, weather officials said.

Icy conditions were expected to last through the weekend from Texas to Ohio to Tennessee, and Virginia officials warned residents of a major ice storm likely to take shape Sunday, resulting in power outages and hazards on the roads.

In California, four people died of hypothermia in the San Francisco Bay area and about a half-dozen traffic-related deaths were blamed on the weather in several states.

Freezing rain and sleet were likely again Saturday night in Memphis, Nashville, and other areas of Tennessee before the storm surged northeast.

Icy, treacherous sections of Interstate 35 north of Dallas were closed for hours at a time over the last day as tractor-trailers had trouble climbing hills, wrecks occurred and vehicles stalled, authorities said.

Texas Department of Transportation spokeswoman Michelle Releford said road graders and more sand and salt trucks were being sent to try to ease the ice problems.

About 400 departing flights from Dallas/Fort Worth International Airport were canceled, about half of the usual schedule, the airport said.

In Virginia, state Emergency Management spokeswoman Laura Southard said the storm had the potential to be a "historic ice event."