A prolonged, dangerous bout of frigid temperatures with snow, sleet, and freezing rain will encompass much of the central and eastern United States this weekend into early next week. To make matters worse, there are fresh model signals that one or more reinforcing rounds of cold and snow may emerge around the end of January and early February, including parts of the mid-Atlantic and Northeast.
The intensity, duration, and geographic spread of this U.S. winter blast could have major consequences, from sustained power outages to transportation snarls and widespread business closures.
The National Weather Service office for the Washington, D.C., area warned on Friday: “The combination of heavy snow and ice alongside prolonged very cold temperatures presents a unique and significant risk to life and property across virtually the entire region.”
As of midday Friday, January 23, nearly all of the contiguous U.S. east of the Rockies was plastered with one or more winter-weather watches or warnings issued by the National Weather Service. Frozen precipitation is not expected in Florida and nearby parts of the Gulf and Atlantic coast, but even these areas will be markedly colder than average for late January.
Daryl Herzmann, the lead for the Iowa Environmental Mesonet sites that the weather community relies upon for many archived datasets, posted on BlueSky this morning that the number of counties under a winter storm warning for this event is second highest since 2008, only slightly trailing February 15, 2021.
How far south – or north – will the heaviest ice and snow develop?
As we noted in a post on Jan. 7, some of the longest-range forecast models were already suggesting that a strong upper-level ridge could develop over western Canada and Alaska by late January, setting the stage for cold air to surge into the United States on the east side of the ridge. As that scenario firmed up, models such as the European and GFS (U.S.) coalesced on the wintry assault now unfolding. By early this week, there was noteworthy model agreement on the overall picture for this weekend.
The factors in play are:
- a sprawling polar air mass at the surface, which was racing southward on Friday as expected
- a pair of upper-level troughs, one in central Canada and another off the coast of western Mexico, that will come into alignment over the central U.S. this weekend, providing the upward lift for precipitation
- very warm, moist air over the Gulf of Mexico that will get drawn northward atop the cold air, providing ample moisture
High pressure centered in North Dakota on Friday afternoon already extended across much of the eastern half of the country. Air temperatures by early afternoon Friday were already near or below zero Fahrenheit from Omaha, Nebraska, to Detroit, Michigan, with even colder wind-chill values. Multiple days below freezing are possible as far south as Dallas-Fort Worth, which will put major pressure on regional power grids.
The bigger forecast challenge has been placing the north-south extent of the heaviest snow and ice, which will extend roughly from the Southern Plains to the mid-Atlantic and Northeast. There’ll certainly be ample fuel for precipitation: Sea surface temperatures over the Gulf of Mexico are close to record highs for late January. But more moisture doesn’t always mean heavier snow: Temperatures aloft still have to remain cold enough for snow production.
Models briefly converged early this week on the idea of epic, potentially all-time-heavy snowfall in places like Oklahoma City and Nashville. But it now appears the surge of warm, moist air from the Gulf just above the cold surface air will be stronger and will push farther north than originally thought as the upper lows orchestrating the flow join forces a bit sooner.
If more recent model runs prove accurate, the snowfall from the Southern Plains to the Tennessee Valley will be significant rather than record-smashing. However, heavy snow could extend from the Ohio Valley all the way into parts of the mid-Atlantic and Northeast. Totals of six to 12 inches are expected along the Interstate 95 corridor all the way from Washington, D.C., to Boston, with higher totals toward the north and just inland from the larger cities. (Near the coast, sleet and/or freezing rain could invade the mix and cut down on total accumulations.)
The juicy Gulf air will also raise the risk of a highly damaging and disruptive ice storm, especially in a belt from eastern Texas through parts of Arkansas, Louisiana, Mississippi, Alabama, Georgia, and North Carolina. In Raleigh, news outlet WRAL warned on Friday in their forecast for Sunday: “We need you to prepare for a few days or possibly more of no power.”
Cold surface air often remains trapped against the eastern slopes of the Appalachians, a feature called “cold-air damming,” which will help keep the warm air aloft from working its way to the surface in parts of Virginia, the Carolinas and Georgia.
Far above the surface – and even above the jet stream – the stratospheric polar vortex is highly elongated. This isn’t quite the same as the polar vortex “splitting” and a lobe heading toward the United States, which is one mode that can help facilitate intense U.S. winter weather. Instead, it’s more of a stretching out – in this case, from the high Arctic to central Canada.
Read: Update: How’s U.S. winter weather changing in a warming world?
In a 2021 Science paper, Judah Cohen (Atmospheric and Environmental Research) presented evidence for an increase in stretching events during the era of “Arctic amplification,” the phenomenon in which the Arctic is warming faster than other parts of the world as a result of climate change. (See our 2025 coverage of the Gulf Coast snowstorm for more background on polar-vortex stretching.)
A chilly wake-up call
This storm sequence is hitting after what’s been a mild winter with little snow from the Great Plains across the South and Southeast. The past 30 days were warmer than average for virtually all of the contiguous U.S., and only 25% of the nation outside Alaska and Hawaii was snow-covered as of January 23, the lowest fraction for that date in records going back to 2003.
The cold of the next few days doesn’t seem likely to be historically extreme in terms of sheer intensity. In fact, the number of daily record lows set could be surprisingly small, given some of the truly fierce Arctic blasts of the 19th and 20th centuries. However, the duration of noteworthy cold may push into once-in-a-generation territory in some places.
For example, the one-two punch of winter storms in Washington, D.C., assuming little temperature recovery in between, could produce a stretch of seven to 10 days at or below freezing. The longest stretch in modern times with high temperatures at or below 32°F at Washington’s Reagan National Airport lasted seven days, on Feb. 9-15, 1979. Nothing longer has occurred since Jan. 23–Feb. 3, 1936, when the nation’s capital failed to rise above freezing for a record-long 12 days.
Jeff Masters contributed to this post.
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