The first major winter storm of the year is endangering a 2,100-mile swath of the country from the Northwest and Plains to the Mid-Atlantic and East Coasts, bringing a variety of life-threatening hazards to major metropolitan areas, including potentially heavy snow, blizzard-like conditions and paralyzing ice accumulations can lead to longer power outages.

WINTER STORM LIVE TRACKER: SNOWFALL MAPS, CURRENT WARNINGS, POWER OUTAGE FORECASTS

The storm is making its way through the northern Rockies and Central Plains on Saturday, hours after ravaging the West Coast and even triggering the first tornado of the year in California.

More than 6 million residents were under winter weather advisories, including winter storm warnings and ice storm warnings, with significant impacts expected between Interstates 50 and 70.

NOAA forecasters and the FOX Weather Center said travel will likely be impossible for some communities as more than a foot of snow will cover some roads despite efforts to prepare pavement for winter weather.

South of the heavy snow band, ice is expected to be problematic, accumulating to nearly an inch from southern Missouri through Kentucky to West Virginia. The heavy glazing is likely to result in power outages and due to the nature of the site, outages could be prolonged.

The arctic air will keep much of the northern parts of the country below freezing for several days due to wintry weather, bringing additional hardships for those unprepared for winter’s plunge.

Biggest snowfall event of the season

Communities in Kansas, Missouri, Illinois, Ohio and parts of West Virginia are expected to see snowfall totals approaching a foot. That makes this winter storm the most significant event of the season and, for some areas, possibly the largest snowfall in over a decade. according to NOAA’s Weather Prediction Center.

Isolated higher amounts are expected in the Appalachian Mountains and along the Great Lakes, where the influence of the terrain will take full effect.

Many cities and towns in the storm system’s catchment area have declared snow emergencies as crews repair major roads and prepare for around-the-clock snow removal.

“That’s the big problem,” Becky Allmeroth, chief safety and operations officer for the Missouri Department of Transportation, told FOX Weather on Friday. “We are informing motorists in advance that our travel will be nearly impossible on some of our major highways: Interstate 70 because of the amount of snow and Interstate 44 – that’s really the slam dunk right now for some of these heavier amounts of ice.”

Heavy snowfall of 5 to 8 inches is expected in the Kansas City, St. Louis and Louisville metropolitan areas, with even higher amounts possible around Indianapolis. Snowfall is expected to reach even Philadelphia and Washington, D.C., where 3 to 6 inches is possible through Monday evening, with isolated higher amounts.

HOW MUCH ICE IS NEEDED TO TURN OFF POWER AND DAMAGE TREES?

Significant amounts of ice could knock out power

An ice storm is likely south of the heavy snowfall, with hours of freezing rain expected, the FOX Forecast Center said.

At least half an inch of ice could accumulate in parts of southern Missouri, southern Illinois and the Appalachian Mountains, causing widespread tree damage and prolonged power outages.

“Traveling is strongly discouraged. If you must travel, keep an extra flashlight, food, and water in your vehicle in case of an emergency. “Prepare for possible power outages,” an NWS meteorologist warned residents in the highest ice probability zone.

The effects of ice formation depend largely on the amount of ice that accumulates on surfaces. When total ice thickness is less than 0.25 inches, impacts are typically limited and result in roads becoming slippery and treacherous. However, if the total ice thickness exceeds 0.25 inches, the weather event becomes more serious, causing power outages and weak tree branches that begin to fall.

Unlike previous winter weather events this season, there doesn’t appear to be much warm air on the horizon, meaning much of the snowfall will remain on the ground for a significant portion of the month.

“On top of that, we have another round of cold air coming in, and then the coldest air after that. So we’ve got a few rounds here that we need to get through,” said FOX Weather meteorologist Steve Bender.

HOW TO WATCH FOX WEATHER

Severe risk of thunderstorms in the south

On the warm side of the storm system, thunderstorms are expected to develop along the Gulf Coast on Sunday and Monday.

Some of these storms are expected to meet severe criteria, with gusty winds and the possibility of tornadoes.

The NOAA Storm Prediction Center has identified a low risk of severe storms from East Texas to West Alabama, rating it 2 out of 5 on the agency’s severity threat scale.

These thunderstorms are expected to impact regions that were recently affected by a tornado outbreak in late December.

Severe thunderstorms in the south are not uncommon during the winter months, as the region is in tornado season.