Roadside cameras operated by the Mississippi Department of Transportation showed semitrucks and pickups bumper-to-bumper on stretches of I-22 lined with snow. The Mississippi National Guard said citizen-soldiers equipped with wreckers began arriving before dawn to help clear I-55 and I-22. Temperatures in the Midwest and Northeast were forecast to remain well below freezing throughout the day Wednesday, according to the National Weather Service. In Nashville, Tennessee, where nearly 100,000 power outages lingered early Wednesday, high temperatures were to rise just above freezing before plunging to 13 F (minus 10 C) overnight. Associated Press writers Jonathan Mattise in Nashville, Tennessee, and Sarah Brumfield in Washington contributed to this report.