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An Arctic outbreak partially tied to the polar vortex encircling the far north is set to bring some of the coldest air in years to locations east of the Rocky Mountains during the next two to three weeks.
Threat level: A high-impact winter storm will bring more than a foot of snow beginning Saturday to places that are unaccustomed to such amounts, including the Kansas City metro area and near St. Louis.
- The storm will help pull more bitterly cold Arctic air southward on its heels, as blustery winds kick in from the northwest. Most of the U.S. will see temperatures dip down to the freezing mark.
- With temperature anomalies of 15°F to 25°F below average for this time of year, the cold will be noteworthy more for its duration than its intensity, however.
- Computer models are still hinting that even more intense cold could move south out of the Arctic later in late January.
- Since January is typically the coldest time of year, any negative temperature departures from average can result in significant cold.
More than half the U.S. population is expected to see temperatures drop to 32°F or below during the next seven days — with many seeing far colder temperatures.
Where it will snow and how much
Zoom in: The National Weather Service is warning of “major” winter storm impacts across central and northern Kansas, into Kansas City, where more than a foot of snow could fall this weekend.
- Unusually heavy snow will also accumulate near St. Louis, where “major” impacts are likely, according to NOAA’s Winter Storm Severity Index.
- For these regions, “This could be the heaviest snowfall in over a decade,” the NWS stated via a post on X.
- Another area of major winter storm impacts is forecast for the Mid-Atlantic, specifically the Baltimore-Washington corridor, where more than 8 inches of snow could fall between Sunday night and Tuesday morning.
- If these amounts verify, it would be the biggest snowstorm in these areas since at least 2022.
The NWS warns areas with major impacts could see “dangerous to impossible driving conditions” along with “considerable disruption to daily life.”
Between the lines: Perhaps the biggest winter storm-related threat is freezing rain.
- To the south of the extensive snow shield, a strip of damaging ice will build up on trees and power lines, potentially knocking out electricity to millions of people from Nebraska to West Virginia.
- Such outages could last many days, particularly because of the lack of experience with such hazards in this region.
- “Widespread tree damage and long-lasting power outages [are] possible in areas with over a half-inch of ice accumulation,” the NWS stated.
The intrigue: After this storm exits into the Atlantic on Tuesday, forecasters will be eyeing both a lobe, or piece, of the polar vortex swirling over Canada, which could be directed southward into the U.S. in about a week.
- Also facing scrutiny will be the potential for any other major winter storms given the cold air entrenched across the U.S.
Fun fact: The annual meeting of meteorologists from around the U.S. and abroad takes place next week, and is infamous for prompting its own extreme weather.
Go deeper:
Arctic blast tied to polar vortex puts U.S., Europe in deep freeze
Polar vortex poised to spin into U.S., leading to frigid January
Major winter storm to usher in Arctic blast for 230 million people