TYLER, Texas (KLTV) - East Texas power companies, including Oncor, are preparing for possible outages as a winter storm approaches. Officials say even a thin glaze of ice could cause big problems. “We prepare year-round for these types of events,” said Oncor’s Tom Trimble.

Strong, gusty winds will lead to dangerous wind chills, prompting extreme cold warnings and watches for the northern Plains and the Upper Midwest.

A major winter storm — among the most extreme and widespread in years — is set to lash more than two dozen states with damaging ice and heavy snow late this week.

A large storm system is expected to hit this weekend, with snow and ice from Texas to the Carolinas and up the Eastern seaboard. The winter system could bring more than a foot of snow.

Snow in the forecast brings more than just a winter wonderland. It also increases the chance of power outages. Winter precipitation can cause power lines to sag, particularly if a snow-laden branch pushes them down. Those power lines can snap, causing outages.

Millions of people are expected to endure the impacts of an ice storm set to march across the U.S. later this week.

The South is bracing for a potentially major winter storm this weekend, impacting Texas, Oklahoma, Louisiana, Arkansas, Mississippi, Alabama and Tennessee.The storm is still several days away, so exact timing and locations are not yet clear.

The sixth wave of rain in the past week will drench parts of San Diego County Wednesday and will be followed Thursday by winds powerful enough to make driving difficult on Interstate 8 east of Alpine and cause widespread power outages, the National Weather Service says.

Millions of students could see classes cancelled for days at a time after a winter storm wallops the U.S. later this week.