(CNN) The winter storm sweeping across the southern United States revealed its power Saturday by dropping 10 inches of snow on Lubbock, Texas -- 2 inches more than the city usually gets in a whole year. 
 
 "They crushed their yearly average in 24 hours," CNN meteorologist Ivan Cabrera said. 
 
 The Lubbock Police Department tweeted late Saturday that black ice and freezing fog were beginning to form on areas Interstate 27. Police said they were "working about 20 wrecks due to these dangerous conditions." 
 
 Right now we are asking citizens to stay off of MSF, I-27 & Loop 289 until further notice! This is because of the black ice and freezing fog. Right now first responders are working about 20 wrecks due to these dangerous conditions. 
 
 Having done its work in Texas, the storm will move east and is expected to pound the Carolinas with heavy snow Sunday, followed by rain, Cabrera said. Sleet and flooding are also possible across the South. 
 
 As much as 6 inches of snow might fall in Charlotte, North Carolina, and ice accumulations of a quarter of an inch to half an inch are possible. 
 
 "Six inches will shut that city down," CNN meteorologist Allison Chinchar said. "It's very much like any other Southern city ... where they don't have the resources that a lot of other cities have. They have few salt trucks, few snowplows. It takes them longer to clean something like that up." 
 
 A #NCwx look at the expected snowfall and ice accumulations from the upcoming #WinterStorm from the seven @NWS offices that serve the state. Get your local forecast: https://t.co/kiwel57HQs pic.twitter.com/MgBUl622Je — NWS Raleigh (@NWSRaleigh) December 8, 2018 
 
 Power outages are likely and air travel will be restricted. More than 1,000 Sunday flights have already been canceled at Charlotte Douglas International Airport, according to FlightAware, a flight tracking service. American Airlines and its regional partners canceled 225 flights Saturday, 1,100 for Sunday and 300 for Monday, American said in a news release. 
 
 Many churches in the Charlotte area have preemptively canceled Sunday services, CNN affiliate WSOC reported , and the city of Charlotte is prepping emergency shelters. Grocery store shelves have been cleared of bread, milk and other staples. 
 
 North Carolina authorities declared a statewide emergency. 
 
 "Snow may be beautiful but it can also be treacherous and I urge North Carolinians to take this storm seriously and get ready for it now," Gov. Roy Cooper said in a statement. 
 
 Very heavy snow is forecast for the Appalachian Mountains, CNN meteorologist Haley Brink said, with Asheville, North Carolina, and Roanoke, Virginia, predicted to get 12-18 inches. Social media showed snow falling Saturday night in Asheville. 
 
 At lower elevations, Raleigh, North Carolina, and Richmond, Virginia, are expected to see 4-6 inches of snow. 
 
 Atlanta will probably see rain but not snow, Cabrera said, though northeast Georgia might. The weather could slow air traffic at Hartsfield-Jackson International Airport. 
 
 More than 25 million people are under winter weather alerts from Oklahoma through Virginia, and more than 10 million are under a flood threat from the Gulf coast to South Carolina. 
 
 Eastern Tennessee, Georgia and the Carolinas 
 
 The culprit is a moisture-heavy storm that brought downpours and flash flooding along the southern edge of Texas and snow and ice in the north. As that moisture moves eastward, it is colliding with a high pressure system over the Ohio Valley that is funneling cold air into the region. 
 
 "It's kind of a big deal," Chinchar said. "It's December. This is not the time of year that they would typically get this stuff." 
 
 Parts of North Carolina could see record snowfall, described by the National Weather Service as a "once-in-a-generation event." 
 
 "This storm comes at a time of year when North Carolinians are usually hearing carols about snow, not actually seeing it. But this time, the real thing is headed our way and North Carolina is getting prepared," Cooper, the North Carolina governor, said, according to WSOC in Charlotte. "A winter storm's not a Christmas carol snow. It's serious, and you need to take steps now to get your family ready." 
 
 The flooding and winter precipitation may also affect Georgia. Heavy rain with 1 to 3 inches is projected Saturday, with "rates expected to be high at times, increasing the threat of flooding," the weather service said. 
 
 About 1 to 2 inches of snow could fall in the higher elevations of North Georgia, with up to 5 inches on the highest ridges Sunday night into Monday. Possible freezing rain and dusting snow could also reach the I-85 corridor. 
 
 Arkansas and western Tennessee 
 
 Half an inch of ice may coat trees and power lines from Little Rock, Arkansas, to Nashville, Cabrera said. 
 
 The National Weather Service predicted 1-3 inches of snow in north and central Arkansas with isolated areas exceeding 4 inches in the northeast. 
 
 The southern half of Arkansas faced up 4 to 5 inches of rain, with flash flooding possible. The higher elevations of the Ozark Mountains were expected to see 2 to 6 inches of snow on top of a glaze of ice up to a quarter of an inch. 
 
 Snow totals will be lower in northeastern Arkansas and northwestern Tennessee, where a trace to 1 inch of snow is possible. 
 
 Texas 
 
 After the heavy rain in Lubbock, many community activities were disrupted. The city holiday parade was postponed and Texas Tech rescheduled all Saturday final exams until Sunday, CNN affiliate KCBD reported 
 
 Morning more snow 12/08/18 Here and Lubbock Texas 🙏🙏🙏 pic.twitter.com/H7vgefj7t0 — Eric Lopez (@EricLop51065391) December 8, 2018 ||||| (CNN) One weather-related death has been reported in North Carolina as a result of this weekend's snowstorm. 
 
 Police in Matthews, about 12 miles south of Charlotte, said a tree fell on a vehicle. This led the vehicle to drive through the front lawn of a church until it hit the front of the building. The driver died and the passenger was taken to a hospital with minor injuries, police said. 
 
 A nasty mix of snow and ice gripped the Southeast this weekend, leading to treacherous driving conditions, canceled flights and thousands of people stranded at home. 
 
 "Over 20 million people are under winter weather alerts, over 8 million people are under a flash flood threat, and over 9 million people are under wind advisories," CNN meteorologist Haley Brink said Sunday. 
 
 More than 12 inches of snow fell Sunday in the southern and central Appalachians, the National Weather Service said. The area with the highest snowfall total was Whitetop, Virginia, at the border of North Carolina, which had 2 feet of snow, according to CNN meteorologist Gene Norman. 
 
 Raleigh-Durham International Airport received about 7 inches of snow Sunday, according to CNN affiliate WTVD , which was the most snow at the airport since 2002. 
 
 Charlotte also saw record-setting snowfall totals. With 2.7 inches, the city had its snowiest December since 1997, according to CNN affiliate WSOC-TV 
 
 Snowfall could total 12 to 20 inches over the Appalachians and into the Carolinas by Monday, when the storm is expected to move off the coast, the NWS said. 
 
 "Snowfall amounts in some locations will likely exceed a foot and result in several days of difficult or impossible travel, extended power outages, and downed trees," the agency said. 
 
 The storm already has knocked out power for more than 546,000 customers in the Southeast. 
 
 The bulk of the outages are in North Carolina, where 244,807 customers are in the dark. In South Carolina, more than 225,600 customers have lost power. And Alabama, Tennessee and Georgia each had about 20,000 and 30,000 customers without electricity. 
 
 A snow-covered car sits outside a home Sunday in Greensboro, North Carolina. 
 
 Those hoping to escape the storm may be out of luck. More than 1,100 Sunday flights into and out of North Carolina's Charlotte Douglas International Airport were canceled, according to flight tracking website FlightAware 
 
 More than half the Sunday flights at Raleigh-Durham International Airport and Piedmont Triad International Airport were also called off. 
 
 Virginia extends winter storm warning 
 
 A winter storm warning is in effect for most of Virginia until to 2 p.m. Monday, Norman said. 
 
 Virginia's western and central areas were also hit with snow. The city of Richmond and surrounding areas received about 9 inches of snow, according to the National Weather Service in Wakefield, Virginia. Areas south of Richmond got 6 to 8 inches of snow, Norman said. 
 
 Like it's neighboring states to the south, Virginia also saw power outages for thousands, and dozens of vehicle crashes. 
 
 As of Sunday, there were more than 15,000 customers without power in the western part of the state, according to Appalachian Power. In the Richmond area, Dominion Energy said there were more than 13,000 without power. 
 
 A snowplow is followed closely by cars as it clears US 301 in Hanover County, Virginia, on Sunday. 
 
 Virginia State Police reported nearly 60 crashes in Virginia because of the snow, with most crashes in the agency's Richmond division. 
 
 "The majority of the crashes involve only damage to vehicles. No traffic fatalities have been reported at this time," Virginia State Police spokesperson Corinne Geller told CNN affiliate WTVR 
 
 Virginia Department of Transportation officials told WTVR Sunday that road crews were working 12-hour shifts until all roads were passable. 
 
 Richmond International Airport reported Sunday that nearly 100 flights had been canceled, WTVR reported . One of those flights, a United Airlines flight to Denver, had passengers on the runway for hours. 
 
 WTVR reported that the flight was supposed to leave at 8 a.m. Sunday, but passengers were stuck on the runway until 11 a.m. after officials said the weather worsened. After deboarding and reboarding the plane, passengers sat on the runway again for four more hours until they returned to the gate at 5 p.m. when the flight was officially canceled, WTVR reports. United officials apologized for the inconvenience. 
 
 North Carolina has 500 car wrecks in 11 hours 
 
 In Durham County, residents typically get about 6 inches of snow over an entire year . But on Sunday morning, they woke up to see 6 inches of snow on the ground. 
 
 "The roads in Durham are treacherous and not safe for driving," the Durham County Sheriff's Office tweeted. 
 
 All that heavy wet #snow is starting to weigh #powerlines and tree branches down. Here on the 2800 block of Beck Rd a power pole has broken. Remember when the power goes out to safely use alternative heating and lighting sources. #NCWx #DurhamWeather #WinterStorm #WinterSafety pic.twitter.com/aikCgH3htM — Durham Sheriff (@DurhamSheriff) December 9, 2018 
 
 Authorities responded to more than 500 car crashes between midnight and 11 a.m. Sunday, North Carolina Gov. Roy Cooper said. One tractor-trailer ran off the road and into a river. 
 
 "We've seen too many collisions," Cooper said. "From Charlotte across central North Carolina, the biggest concern now is ice making roads even more dangerous." 
 
 A man tries to walk through blowing snow Sunday in Wake Forest, North Carolina. 
 
 Even before the storm hit, Cooper declared a statewide emergency. Grocery store shelves were cleared of bread, milk and other staples. 
 
 Cooper asked residents to check on vulnerable loved ones and the elderly, if possible. He said 11 emergency shelters have opened across the state. 
 
 North Carolina Highway Patrol said anyone who must drive should leave twice as much following space as normal behind the next car, in case that vehicle loses control. 
 
 Driving conditions remain hazardous. If you do not have to leave your home, please do not. If you must leave, be sure to slow down, increase following distances, have emergency supplies on hand and expect delays. #wintersafety #winterstorm pic.twitter.com/QYKZbJQU46 — NC Highway Patrol (@NCSHP) December 9, 2018 
 
 'Ice is becoming a big problem' in South Carolina 
 
 In South Carolina, a state known for palmettos rather than freezing rain, ice-covered roads were making driving conditions perilous. 
 
 It's never a good idea to be out on the roadways in winter weather, but when snow switches to nothing but ice, even a 4x4 will struggle. pic.twitter.com/MDwCpEz3Z7 — Trooper Bill SCHP (@SCHP_Troop3) December 9, 2018 
 
 The Greenville-Spartanburg area received between 2 inches and more than a foot of snow, NWS reported Sunday. 
 
 "Ice is becoming a big problem. Please stay off the roads," Greenville County Emergency Management pleaded. 
 
 The local National Weather Service office had to adjust its forecast map Sunday after it became clear more ice was expected near Interstate 85. 
 
 "We have increased our ice (accumulation) forecast quite a bit along the I-85 corridor," the NWS Greenville-Spartanburg office said. 
 
 The storm left a trail of misery in Texas 
 
 Before striking the Southeast, the moisture-heavy storm walloped Texas, causing flash flooding along the southern edge of the state and snow and ice in the north. 
 
 As the moisture moved east, it collided with a high-pressure system over the Ohio Valley that was funneling cold air into the region. 
 
 snow making my univ even more beautiful pic.twitter.com/WOLJU5vSNC — Kinsey Priesmeyer (@kpriesmeyer_) December 8, 2018 
 
 Parts of Lubbock were buried under 10 inches of snow, 2 inches more than the city usually gets in a whole year. 
 
 "They crushed their yearly average in 24 hours," CNN meteorologist Ivan Cabrera said. 
 
 More flight cancellations to come 
 
 Grounded airline passengers might remain stuck Monday as more flights get canceled. 
 
 The Charlotte airport said it expects cancellations through Monday morning, mostly involving small, regional planes. 
 
 American Airlines, whose second-largest hub is in Charlotte, has canceled 1,100 flights for Sunday. It's not clear when those passengers will be able to get on board, since another 320 flights scheduled for Monday already have been nixed.
– Real-live winter in the South? You bet: Unlikely ice storms hammered southern states yesterday, depriving thousands of power, forcing hundreds of flight cancellations, and killing at least five people, CNN reports. It's not over, either: Storms are poised to strike regions from Dallas to Memphis until tomorrow and Arkansas through Monday. The north will also get its share, with sleet or snow hitting central New England through the central Appalachians into today, and blanketing the nation's capital tomorrow. In other details: Dallas/Forth Worth had it worst, canceling nearly 700 flights and the downtown Dallas holiday parade for the first time in 26 years. The storm cut out power for more than 200,000 customers. Temperature swings were shocking: In Hot Springs, Arkansas, a temperate 75-degree day on Wednesday turned into an ice storm yesterday. Most fatalities occurred on icy roads, including the death of Granby, Missouri, Mayor Ronald Arnall, whose car veered off a state highway in southern Missouri and hit a tree, Reuters reports. Oklahoma alone has recorded about 116 storm-related injuries. A new storm struck the Pacific Coast yesterday, dropping pretty heavy snow on Portland. Even Las Vegas might see snow today—up to 2 inches. But it's not so bad by comparison: In northern Europe, a powerful storm with hurricane-force winds kicked up a huge tidal surge and killed 8 people, CBC News reports.