Tree limbs snapped with a sound like gunshots, blacking out thousands of homes and businesses, and schools and government offices were closed as a major storm spread a glaze of ice and snow from the southern U.S. Plains to the East Coast.
At least 19 deaths had been blamed on the weather.
Highway crews fought to keep up with slippery roads and in some places were blocked by fallen tree limbs and power lines. Ice had built up 3 inches thick in sections of Arkansas and Oklahoma.
The National Weather Service posted ice storm and winter storm warnings Tuesday along a broad swath from Texas and Oklahoma through the Mississippi and Ohio valleys all the way into northern New England. Radar showed smears of snow and freezing rain stretching from Texas to Pennsylvania during the evening.
Broken tree limbs weighted down by ice crashed onto power lines, cutting service to at least 165,000 homes and businesses in hard-hit Arkansas, utilities said. Arkansas utilities warned customers that their power could be out for at least three days.
"Trees are falling everywhere you look. It's amazing. I saw power lines broken in half," said Nancy Stears, 37, of Midway, Arkansas, in a Taco Bell restaurant that had briefly managed to stay open despite the ice.
Kentucky state officials reported more than 80,000 customers with no electricity as ice up to 1.5 inches thick broke tree limbs.
"You hear the popping — it sounded like gunfire — and it's limbs from trees breaking," said Hopkins County, Kentucky, Judge-Executive Donald Carroll, who was among those with no power. He said crews in his western Kentucky county were busy trying to clear broken branches from roads.
Emergency shelters were set up in several western Kentucky communities.
About 25,000 customers were blacked out in Oklahoma. More than 42,000 outages were reported in southern and eastern Missouri.
Kentucky Gov. Steve Beshear declared a statewide emergency Tuesday; Oklahoma Gov. Brad Henry did the same on Monday.
Hundreds of public schools, colleges and universities called off classes Tuesday in parts of Arkansas, Oklahoma, Ohio, Indiana, Kentucky, Illinois, Missouri, West Virginia and Maryland.
Arkansas state government offices opened two hours late because of the weather. All but essential state workers in Oklahoma were told to stay home. West Virginia state offices shut down early.
The New Hampshire Legislature canceled Wednesday's sessions. Up to 15 inches of snow was forecast Wednesday in New Hampshire.
Since the storm began building on Monday, the weather had been blamed for five deaths in Texas, three in Arkansas, three in Virginia, five in Missouri, two in Oklahoma and one in Indiana.