Historic winter storm on tap? System expected to bring Washington’s heaviest snow in years

A potentially historic winter storm will bear down on Washington this weekend, threatening to deliver the most significant snowfall the region has seen in years alongside dangerously cold temperatures that could linger for days.

The National Weather Service has issued a Winter Storm Watch for the District and surrounding areas from Saturday evening through Monday morning, warning of heavy snow mixed with sleet and freezing rain. Forecasters say there is a high likelihood of at least 5 inches of snow across the region, with some areas potentially seeing over 10 inches.

“A large area of precipitation will overrun Arctic air in place over the Mid-Atlantic,” the National Weather Service Baltimore/Washington office stated. “This will likely lead to widespread significant snow beginning late Saturday, with the potential for ice Sunday especially south of Highway 50 and near and east of Interstate 95.”

Arctic blast sets the stage

The weekend’s weather threat consists of two distinct but related components: the dangerous Arctic air mass already sweeping across the country, followed by the major winter storm that will interact with the frigid temperatures.

The Arctic blast moved into the Northern Plains and Upper Midwest on Thursday, bringing what the Weather Prediction Center described as “dangerously cold and very dry Arctic air.” Wind chills in some areas of the Northern Plains could reach 50 degrees below zero.

For Washington, a Cold Weather Advisory takes effect Friday evening through Saturday morning, with wind chills expected to drop as low as 8 degrees below zero. The extreme cold will ensure that precipitation falls entirely as snow when it first arrives Saturday evening.

Timeline and uncertainty

The winter storm will track from the Southern High Plains on Friday, across the Mid-South and Ohio Valley on Saturday, before reaching the Mid-Atlantic and Northeast on Sunday. Over 160 million Americans across more than 40 states are under winter weather alerts.

For the District, the first snowflakes could appear Saturday evening between 8 p.m. and midnight. However, the extremely cold and dry air in place may cause some initial precipitation to evaporate before reaching the ground, potentially delaying accumulation by a few hours.

Once snow begins sticking, forecasters warn it could intensify rapidly. The National Weather Service indicates snowfall rates could reach one to two inches per hour late Saturday night, with visibility potentially dropping to one-quarter mile or less.

The critical uncertainty centers on Sunday afternoon, when some computer models suggest warmer air aloft could change snow to sleet and freezing rain, particularly south of Highway 50 and along the Interstate 95 corridor. This possibility has created a wide range in snowfall forecasts.

“The big question this afternoon is, will this be an all-snow event, or will some milder temperatures sneak into the middle levels of the atmosphere and change parts of the region over to sleet or even freezing rain on Sunday afternoon,” FOX 5 DC meteorologist Mike Thomas wrote.

If significant icing occurs, the Weather Prediction Center warned of “the potential for long duration power outages, extensive tree damage, and difficult to impassable travel conditions.”

Snowfall forecasts vary widely

Specific accumulation predictions depend heavily on whether and where any changeover to ice occurs.

7News meteorologists predict 7 to 11 inches for Washington with 70 percent confidence, though totals could range from 5 inches to more than 12 inches. FOX 5 DC suggests 8 to 14 inches for the District, with higher amounts of 12 to 18 inches possible northwest of the city where all-snow conditions are more likely.

Just In Weather analysis by meteorologist Justin Berk shows 100 percent confidence that Baltimore will receive at least 6 inches, with an 80 percent chance of 12 inches or more in areas north and west of the city.

These would be significant totals for a region that has seen only two snowstorms exceeding 10 inches in the past decade: 17.8 inches in January 2016 and 10.3 inches in January 2019.

Winter storm preparations underway

Local jurisdictions are mobilizing resources ahead of the storm. The District’s Department of Public Works has deployed approximately 200 city trucks and 100 contractors, with crews beginning to pretreat roadways Thursday night.

Warnique West, the District’s director of snow operations, urged residents to stay at least 100 feet back from snow plows and to move vehicles from emergency snow routes.

Maryland Gov. Wes Moore declared a state of preparedness, with the Maryland National Guard preparing personnel and specialized vehicles for deployment across the state.

An extended deep freeze will grip the region

Perhaps more concerning than the snow itself is the prolonged cold expected to follow. Temperatures are forecast to remain below freezing through much of next week, with morning lows potentially dropping below zero in areas north and west of Washington.

“A prolonged period wind chills in the teens and single digits is likely beginning Friday evening and lasting through the middle of next week, with sub-zero wind chills possible at times,” the National Weather Service stated.

This extended cold snap will cause snow and ice to persist on roadways for days after the storm, potentially impacting travel well into next week. The National Weather Service noted that with temperatures so low, road chemicals will not work as effectively as they would closer to the freezing mark.

The Weather Prediction Center emphasized that residents should finish preparations now, including obtaining necessary groceries and medicines that may be inaccessible this weekend into early next week. The National Oceanic and Atmospheric Administration is deploying Hurricane Hunter aircraft to sample the developing storm system, which should provide better data to help forecasters narrow the range of potential outcomes before the first flakes fall Saturday evening.