Atlanta, Georgia (CNN) -- Temperatures were slowly warming Thursday across the South, where freezing rain glazed roads with ice, but a sprawling winter storm system remained in place across the upper Plains states.
The National Weather Service issued winter storm warnings and advisories for more than a dozen states. The brunt of the system is poised to hit Kentucky, Virginia and West Virginia, but several inches of snow are forecast for portions of Indiana, Ohio, Tennessee and North Carolina, as well as Minnesota and the Dakotas. Winter weather advisories stretched into Wisconsin and Minnesota.
In Kentucky, up to a quarter-inch of ice could accumulate on roadways, the weather service warned, in addition to previously fallen snow. Three to six inches of snow were forecast for eastern Virginia.
The low pressure system laid down an icy path across northern Georgia, Alabama and Mississippi on Wednesday. Scores of traffic accidents were reported Wednesday night and early Thursday.
"I personally slid through two intersections," one traveler said in Cherokee County northwest of Atlanta. "I spun out a couple of times."
"I grew up in Chicago, for God's sake," another driver said. "This is an absolute disaster."
However, no significant power outages accompanied the wintry weather in Georgia. Fewer than 500 customers were without power as of about 11 a.m. Thursday, Georgia Power reported.
Delays were reported at Washington's Reagan Airport and Atlanta's Hartsfield-Jackson International Airport on Thursday, according to the Federal Aviation Administration's flight status website.
"Winter weather in the Midwest & Southeast has impacted travel to, from, and through Iowa, Minnesota, North Dakota, South Dakota, Wisconsin, Michigan, Ohio, Georgia, Tennessee, and Kentucky," said an advisory Wednesday on the website for Delta Airlines, the largest carrier in Atlanta.
AirTran Airways warned that the wintry weather could result in flight delays and cancellations, according to a company statement.
AirTran passengers scheduled to travel either to or from Atlanta, Georgia, between 7 p.m. Wednesday and noon Thursday will be permitted to change their reservation without penalty as long as the travel is completed within three days of the originally scheduled departure date, the statement said.
Up to a half-inch of ice was forecast to accumulate across Kentucky and Tennessee and into northern Mississippi and Alabama, raising the risk of downed power lines for residents across the region, the National Weather Service said.
Two people died in a wreck on an icy bridge in Alabama on Wednesday, officials said, and another died in a car accident in Mississippi.
Areas from Minnesota to Ohio to New York have seen more than a foot of snow in the past several days.
The harsh weather stranded about 300 people in Canada Tuesday after what a local official called the most brutal storm to hit the Ontario region in more than two decades.
Some people had been stuck in their vehicles for more than 24 hours after blinding snow piled up so high that opening vehicle doors proved nearly impossible.
By Wednesday, officials said everyone had been rescued.
On Tuesday, record lows were set from Virginia to Florida. High temperatures were 30 degrees below average for this time of year.
The cold air lingered again Thursday morning, with freeze warnings posted as far as south as Boca Raton, Florida.
But Florida's winter fruit and vegetable crops have so far survived the freezing temperatures without too much damage, industry officials said Tuesday.
CNN's Ed Payne, Vivian Kuo and Ashley Hayes contributed to this report.