It was more snow than Baltimore saw in the famed "Knickerbocker" storm of 1922. More than the blizzards of '83, and '96, and '03. It even surpassed the back-to-back "Snowmageddon" storms of 2010 – individually, not combined.
The preliminary measurement of 29.2 inches of snow at Baltimore/Washington International Thurgood Marshall Airport from Friday night through 7 p.m. Saturday should make this weekend's storm No. 1 in the record books.
And with the historic snowfall comes an arduous cleanup.
It could take days to clear, officials warned, with plows and snowblowers not expected to start getting ahead of the more than 2 feet of drifting snow until Sunday.
The storm that delivered on forecasts to become a classic and powerful nor'easter, enhanced by El Niño moisture, buried parts of Virginia and West Virginia with as much as 40 inches of snow. It was potentially one of the five biggest storms to hit the Interstate 95 corridor from Washington to New York, and blamed for at least 12 deaths, mostly in traffic accidents.
At least one person died in Maryland as a result of the storm after suffering a heart attack while shoveling in Abingdon. The weight of the historic snow collapsed roofs on a warehouse in Jessup, a school fieldhouse in Towson and a Safeway supermarket in Bel Air, but no one was reported hurt. Combined with the wind, it caused thousands of power outages around the region.
Officials in Baltimore and surrounding counties said they don't expect plows to reach some streets until Monday, though a rebound in temperatures Sunday and Monday could help the cleanup along. Roads became so treacherous Saturday evening that city officials banned all traffic except emergency vehicles and snowplows, and state officials closed Interstates 70 and 270.
Even some National Guard Humvees brought in to assist city emergency responders were struggling on the streets.
"While we are prepared more than we've ever been for a snowstorm, a storm of this magnitude requires patience," Mayor Stephanie Rawlings-Blake said. "Don't panic if you haven't seen a snowplow on your street. We have a big city and there's a lot of snow to move."
The storm behaved largely as expected, matching or exceeding the snowfall accumulations that often-finicky weather models predicted would happen nearly a week in advance.
"We've been forecasting it to be doom and gloom for the past five days," Andy Woodcock, a meteorologist at the National Weather Service's Baltimore/Washington forecast office, said Saturday afternoon. "This is certainly one for the record books, or the memory books if nothing else."
The historic snowfall made its way into Baltimore's top 10 list of biggest snowfalls by early afternoon, posting nearly 20 inches by 1 p.m. Over the next six hours, it pushed its way to the top of the list. The tally is likely to be revised, with light snow still falling into the night and planned review of the measurements by meteorologists.
The blizzard of Feb. 16-18, 2003, was the record holder, with 26.8 inches of snow.
Some of the highest snowfall totals in the region as of early Saturday evening included 35 inches in New Market in Frederick County, 31.8 inches near Westminster, 30.1 inches near Reisterstown, 29 inches in the McDonogh area of western Baltimore County, 28.5 inches in Bel Air, 27.7 inches near Columbia and 24.8 inches near Cylburn Arboretum, according to the National Weather Service.
It was not clear if the storm was technically a blizzard, though the National Weather Service issued blizzard warnings from Washington to New York. Blizzards require at least three hours of 35 mph winds blowing snow and limiting visibility to a 1/4 mile or less.
Winds peaked at 36 mph during the noon hour at BWI, but otherwise, gusts were in the 25-30 mph range. Visibility hovered at 1/4 mile in the morning hours and improved around midday before dropping to 1/8 of a mile in the afternoon.
"It's very hard for the metro areas to get a verified blizzard," said Troy Arcomano, a winter stormcaster for meteorology website Foot's Forecast and a sophomore meteorology student at the University of Maryland, College Park.
Rich Foot, the website's founder, said confirmation of a blizzard was less important than the National Weather Service's use of the term in watches and warnings to convey the danger of the storm.
"The average Marylander is going to feel like they got blizzarded," Foot said.
As heavy snow continued Saturday, Baltimore police officers were investigating overnight break-ins at four pharmacies across Baltimore, and firefighters were called in the early morning to a burning home in Northeast Baltimore in which an elderly man died.
In addition to the person who died in Abingdon, Harford County officials reported a second death in Aberdeen but said the cause was unknown Saturday afternoon. Two other people in the county reported heart attacks, Harford spokeswoman Cindy Mumby said.
Swirling and drifting snow hindered plowing efforts during the storm, and that could stretch cleanup efforts well into the coming week, officials warned.
Rawlings-Blake said that the city took lessons from the February 2010 "Snowmageddon" storms to speed up efforts to clear roadways, but that it nevertheless may take a couple of days to finish the job. The city hired extra private contractors to help remove snow from neighborhood streets, and it lined up contractors to haul snow away, as well, she said.
Baltimore transportation director William Johnson said crews were fighting the rapid snowfall and blustery winds all day Saturday. They hoped to keep no more than 4 or 6 inches of snow from accumulating on emergency routes to ease efforts to clear the pavement later. Once the snow stopped, crews planned to plow through the night and into Sunday and Monday, he said.
Other counties and municipalities told residents to expect a longer wait until all roads are cleared.
Baltimore County told residents via Twitter that crews would start tackling side streets Saturday night, and expected to finish clearing roads Monday night.
Howard County officials expect main roads to be in good condition by Monday morning, but warned it could be until Wednesday or Thursday until all of the county's 4,100 streets are cleared, spokesman Mark Miller said.
In Annapolis, Mayor Mike Pantelides ordered all traffic except emergency vehicles and snow removal equipment from roadways Saturday. The city has a six-day timeline for clearing all roads, city spokeswoman Rhonda Wardlaw said.
Carroll County spokeswoman Deborah Lundahl said plow drivers were doing their best to reach every portion of the county in a timely manner.
Once the last outer bands of the storm move out by early Sunday morning, sunshine is forecast to help speed the melting, but with so much snow it will take time. Winds could continue blowing snow for the first half of Sunday and temperatures could stay below freezing all day.
High temperatures are forecast in the upper 30s Monday under mostly sunny skies, and in the mid-40s with possible rain showers Tuesday. But then more cold is expected to prevent any fast melting of what is sure to be left over.
Baltimore Sun Media Group reporters Jessica Anderson, Andrew Michaels, Bryna Zumer, Jacob deNobel, David Anderson and Fatimah Waseem contributed to this report.