Maps show where winter storm threatens to bring heavy snow, ice, brutal cold this weekend
More than 200 million people across the United States are bracing for the arrival of a major winter storm that is set to take hold over the weekend. About 175 million are under winter weather or extreme cold alerts, as the system threatens to bring a mix of frigid conditions to a 2,000-mile expanse of the country. Meanwhile, roughly 132 million are under alerts for snow, sleet and freezing rain, according to the National Weather Service.
The storm is shaping up to begin in the southern Plains on Friday before moving across the South and into the East Coast. Heavy snow, ice and brutal cold are expected to make the storm a potentially life-threatening weather event for a huge portion of the country — 35 states.
From the Rockies to the East Coast, forecasts show about two-thirds of the U.S. could be affected by what will likely be the largest winter storm in at least five years. As the system pushes east, temperatures through the weekend are expected to sink to record lows across parts of the southern Plains and mid-Atlantic regions, with people around Washington, D.C., and Raleigh, North Carolina, potentially experiencing those areas' coldest stretches since 2018.
Maps show what to expect from the winter storm
A low-pressure system is forecast to develop in the Southwest and interact with incoming Gulf moisture and Arctic cold air. Forecast models indicate it will begin dropping precipitation on Friday in the southern Plains.
The system is expected to slowly move eastward, bringing snow and accumulating ice. Forecast models continue to change as the event nears, but it is set to impact broad swaths of the U.S., from Arizona to Maine, said National Weather Service meteorologists Rich Otto and Tony Fracasso, of the agency's Weather Prediction Center.
Heavy snow is expected over a wide band of the country, with a foot or more potentially headed for parts of the Texas Panhandle and the Ozarks, Otto and Fracasso told CBS News. The highest snowfall totals — possibly up to 2 feet — could accumulate in the central Appalachians and into the Northeast, they said.
Meanwhile, the polar vortex that is usually situated over the North Pole is forecast to dip down into the eastern half of the U.S. starting Thursday and lasting through the first half of next week.
This will make temperatures drop well below average for this time of year and even bring record-breaking temperatures to some locations. Frostbite can occur in as little as 5 to 10 minutes if exposed to this dangerous cold. Wind chill temperatures are forecast to feel like 40 to 50 degrees below zero in some places across the northern U.S.
Ice is expected to accumulate along the southern side of the storm's track, but considering its slow movement, the amount of accumulation is expected to be between two-tenths of an inch to up to half an inch. Impacts of this magnitude can bring down power lines. With the harsh cold in place, power outages could leave people freezing without indoor heat in some communities.
Parts of northeastern Texas, northern Mississippi and southwestern Tennessee will likely feel the most substantial effects of the ice, said Otto and Fracasso. They noted that icy conditions are also expected to have significant impacts on a block of the eastern U.S., from northern Georgia into the Carolinas.
Possible snowfall amounts are still in flux for individual locations as forecast models continue to come together. But up to 5 or 10 inches is already expected across the southern Plains as the system takes shape over the region on Friday into Saturday.
As this system moves east, snowfall amounts will vary depending on location.
Winter storm may impact travel plans
Travel is likely to be disrupted by weather conditions on roadways and at the airports. Some airports in the South do not have deicing equipment for aircraft to take off safely, possibly leading to widespread cancellations and delays over the weekend.
Some airports that could see issues are Dallas Fort Worth International Airport; Will Rogers International Airport in Oklahoma City; Clinton National Airport in Little Rock, Arkansas; Memphis International Airport and Nashville International Airport in Tennessee; and Hartsfield-Jackson Atlanta International Airport.
The roads could also become very difficult to navigate if not impossible with slick conditions on major interstates such as I-10, I-20, I-30, I-35, I-40, I-44, I-49 and I-55.
Travel on the roads is highly discouraged through the weekend, but if it's absolutely necessary, people are advised to drive with caution.
"Treacherous and hazardous driving conditions are likely due to both the ice and snow accumulations. In some areas, travel will become nearly impossible during the peak of the storm," said Otto and Fracasso. "The extreme cold that follows the storm will prolong the potential impacts, with many areas not getting above freezing for much of next week."
Officials urge drivers to consider taking a winter storm kit with them, including such items as booster cables, a flashlight, a shovel, blankets and extra clothing as well as water, a first aid kit and anything else that would help survive being stranded.
Reasons for forecast uncertainty
After weather prediction models showed considerable variation in their winter storm forecasts earlier in the week, the uncertainty is decreasing as the storm's arrival nears.
Those variations seen earlier in the week were not unusual, said Otto and Fracasso, adding that there can be significant differences "among forecast models 3-4 days ahead of the start of a storm."
Predicting winter storms can carry an additional layer of uncertainty, as freezing temperatures create another variable in the forecast.
"For winter storms, the uncertainty is compounded due to the uncertainty in total precipitation amount in addition to the type of precipitation that may fall," said Otto and Fracasso. When the type of precipitation is snow, very slight atmospheric changes like temperature variations of just one or two degrees can alter the forecast dramatically, they added.