LUBBOCK — The impacts of an ice storm that was moving into North Texas late Thursday could be worse than the snowfalls in the days leading up to the Super Bowl two years ago.

LUBBOCK — The impacts of an ice storm that was moving into North Texas late Thursday could be worse than the snowfalls in the days leading up to the Super Bowl two years ago.

National Weather Service meteorologist Victor Murphy in Fort Worth said the half-inch of freezing rain expected to hit the Dallas-Fort Worth area could also cause power outages in addition to glazing roadways.

"The one big wild card could be ice on tree limbs, purely ice," he said. "That would be my biggest fear: power outages."

Oncor, the energy company that serves about 10 million households across the state of Texas, was preparing for possible outages in North and Central Texas. At a facility in Lancaster, crews prepared backup transformers should bad weather cause mass power outages.

"They can take all the pre-emptive steps they want," Murphy said. "The question would be: How quickly can they get out to access" outages?

The half-inch of freezing rain forecast for Dallas-Fort Worth is about the liquid equivalent of the snow that fell over three days in the week leading up to the 2011 Super Bowl played in Arlington. The freezing rain will fall for as long as nine hours, Murphy said. In 2011, the 3 inches of snow that fell Feb. 1-4 came over three days.

The cities of Dallas and Fort Worth and the North Texas Tollway Authority were preparing scores of dump trucks to spread sand and de-icing agents along bridges, overpasses and thoroughfares.

The temperatures across North Texas won’t get above freezing until at least Monday, Murphy said, meaning ice coating roads, bridges and overpasses won’t melt until at least then.

Texas Department of Transportation spokesman Tony Hartzel said crews in Denton, Collins and Dallas counties pretreated roadways to keep them passable. Liquid magnesium chloride, a salt that prevents the formation of ice on roads, was being applied on Interstates 35 and 20, and U.S. 67 and 75 in the three counties. Only bridges and overpasses on major thoroughfares in Navarro, Rockwall, Ellis and Kaufman counties were being treated, he said.

Officials at Dallas/Fort Worth International Airport advised passengers and those meeting flights to check with their airlines for the latest information, or check the Flight Information page at Airlines were ready to begin de-icing planes when the freezing rain arrived.

American Airlines and American Eagle canceled nearly 500 flights as the wintry blast swept across much of the U.S. Fort Worth-based American announced the cancellations systemwide in anticipation of deteriorating travel conditions.

Dallas-based Southwest Airlines did not cancel any flights Thursday but was monitoring the worsening weather. A travel advisory was posted on its website warning of the possibility of flight delays, spokeswoman Michelle Agnew said.

Officials with Dallas-based Greyhound Bus Lines Inc. had no immediate reports of cancellations Thursday but advised travelers to check the carrier’s website.

A spokeswoman for ERCOT, the operator of the electric transmission grid for most of Texas, said there will be enough power to handle usage during the storm. But, Robbie G. Searcy said in an email, ERCOT may ask customers to cut their usage should there be significant failures at power plants.

Dallas residents were bustling to get prepared for the storm. At a Home Depot, aisles and checkout lines were jammed with shoppers. Firewood and ice melt were in short supply during the day, store manager James McGilberry said

"Some of them know exactly what they want and they just grab as much as they can," he said. "Some of them we have to coach and teach just what kind of device do they need to keep their pipes from freezing."

Motorists across much of West Texas faced slick roadways earlier Thursday as the winter storm brought sleet and freezing rain.

A West Texas man was killed in an accident caused by slick road conditions. Francisco Javier Alvizo, 34, of Lubbock died on Texas 114 in a two-vehicle wreck early Thursday.

Weather service meteorologist Brad Charboneau in Lubbock said the region’s winter storm advisory called for a quarter-inch of freezing precipitation Thursday. By midmorning a layer of thin ice had coated roads in Lubbock.

"Ice is challenging for everybody," Charboneau said. "It’s a whole other animal" from snow.

The wintry mix was worse in areas south of Lubbock, including Midland, he said.

The freezing precipitation was expected to transition to snow as the storm moved northeast. The system brought dramatically colder temperatures across much of the country.

Areas northwest of Lubbock were forecast to get about 2 inches of snow. Lubbock was expected to get about an inch, Charboneau said.

Temperatures in West Texas are expected to stay in the 20s Thursday and Friday.

Traffic along Interstate 27 in Lubbock was moving slowly Thursday, said Leilani Pierce, a manager at Flying J Travel Plaza.

Many truckers had already decided to pull off the interstate, she said. About 40 of the truck stop’s 76 spaces were occupied by midmorning Thursday but she didn’t know how many of those were because of the weather.

About 70 miles north of Lubbock in Tulia, Pilot Travel Center manager Linda Juarez said snow started falling around noon and truckers on I-27 weren’t experiencing much difficulty.

"So far, so good," she said. "Right now they can do what they want."