If you're traveling across the U.S. this week, you might feel summer in one spot and winter in another: The National Weather Service is predicting temperatures hitting record highs and lows, while a huge winter storm "will plague a large portion of the country."
Some areas will see both extremes. After warming up to nearly 80 degrees on Thursday, the Washington, D.C., region will fall below freezing late Friday, with snow and rain likely on Saturday, the NWS says. Many places also will see strong winds.
The weather agency said on Monday that "confidence is high that this winter storm will be extremely disruptive to travel, infrastructure, livestock, and recreation in affected areas."
A 'massive winter storm' will hit much of the U.S.
"A massive winter storm is expected to impact much of the U.S. this week with a variety of hazards," including heavy snowfall, sleet, freezing rain and severe thunderstorms, the NWS said on Monday.
Parts of the Northwest were already feeling the storm early Monday, with snow falling in the Cascades and Northern Rockies. The large system is forecast to expand into California and the Southwest even as it moves east.
In Los Angeles and southwest California, it will be "the coldest storm of the season, and possibly of the last several years," the local NWS office said. As LAist reports, the storm could bring snow and graupel — fragile pellets that form around snow crystals.
By Wednesday, the forecast map shows, active snowfall likely will stretch across a huge swath of the country, from Arizona and Nevada to Minnesota.
"Storm total snowfall will likely be measured in feet for many of the mountain ranges across the West," the NWS said.
The system is driven in part by an "energetic upper-level pattern," the NWS said. At the same time, the agency says, two fronts will push southward from Canada down into the western and central U.S., bringing "significant, widespread snow" and other hazards.
'Numerous' record highs could also be set this week
The term the NWS Climate Prediction Center and many forecasters are using to describe the overall weather pattern is "anomalous" — for the unusual cold and warmth that people will experience.
In the East, people living in areas ahead of the storm can be forgiven for wondering if winter is already over, as they watch early blooms emerge. Temperatures on Monday were forecast to be 10 to 20 degrees warmer than normal across the central and eastern U.S.
As it alerted people to the winter storm, the NWS also predicted "even more anomalously warm highs in the East, with numerous record high maximum temperatures possible."
This mean maximum temperature anomaly forecast graphic tells the story early this week through next weekend:
— National Weather Service (@NWS) February 19, 2023
-West and Upper Midwest: Below normal high temperatures by as much as 25 degrees
-Southeast quad of the U.S.: Above normal temperatures and likely numerous record highs pic.twitter.com/BmEoPQym58
"Highs Tuesday will be similarly above average for most locations, including 70s expanding northward into the Mid-Atlantic," the NWS said, "with only the northern tier cooling off as the clipper system passes through."
Much of the Northeast isn't likely to see as much snow accumulation as in the West, forecasts say, but they could still see freezing rain and ice. And people in Maine and parts of New England — where temperatures were expected to flirt with record highs on Monday — are also on the alert for a significant winter storm to hit, from Wednesday night through Friday.
The pattern of anomalous temperatures is expected to hold sway through at least the first days of March, the Climate Prediction Center says.
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