Meteorologists were expecting the heaviest snowfall of an already frigid and snowy season Thursday, with the region forecast to wake up to a blanket of snow and to endure an icy mix of precipitation through the afternoon.
The National Weather Service was expecting six to 10 inches of snow across the Baltimore area by Thursday night, with higher accumulations north and west of the city. Possible sleet or rain closer to Interstate 95 and the Chesapeake Bay could reduce snowfall in those areas.
The heaviest snow was expected overnight, through daybreak Thursday, and meteorologists remained uncertain Wednesday on exactly when and to what degree warm air in the atmosphere might limit snowfall.
Officials nevertheless cautioned residents to expect snow-covered roads and possibly widespread power outages. Snow was expected to be wet and heavy, weighing on tree limbs weakened by past storms, and gusty 15-30 mph winds were expected to send branches swaying.
Many heeded the warnings by Wednesday evening as residents stockpiled provisions and school systems and state offices closed for Thursday. Flight cancellations also started piling up in advance of the storm.
Gov. Martin O'Malley warned of a "24-hour event" that will bring "a big swath of nasty snow and ice" to the state. He declared a state of emergency Tuesday, while the National Weather Service issued a winter storm warning through early Friday morning.
"Neighbors should stay off the roads," O'Malley said.
The storm was considered to be a classic nor'easter, with a moist system coming up from the Southeast and merging with colder air from the north off the Carolinas. It brought a thick layer of ice to Atlanta and snow across the western Carolinas before heading northeast toward Maryland and beyond, into New England.
It was forecast to intensify over the Mid-Atlantic, bringing snowfall rates of an inch or more per hour overnight. This snow should be unlike earlier snows this winter that were dry and fluffy amid bitter cold, with temperatures forecast to straddle the freezing mark Thursday.
"Whenever you have these situations where we're worried about a changeover to rain, it indicates the snow that's falling is going to be of the wet variety," said Randy Adkins, a meteorologist with AccuWeather.com.
Snowfalls were expected to easily surpass a foot near Westminster and Frederick, though, if air stays colder than expected, such accumulations could also be measured closer to Baltimore, forecasters said.
Baltimore Gas and Electric Co. was preparing Wednesday for widespread power outages, mobilizing its own crews and others from outside the state at staging areas across the region. The Maryland Public Service Commission said it was working with state utilities and the Maryland Emergency Management Agency to stay on top of anticipated outages.
With fresh memories of outages last week, some of which lasted for days, many people bought extra provisions. Some of the most popular purchases at Eddie's of Roland Park included cake mixes, ingredients for chili, marshmallows, frozen pizza and deli meats, said Michael Schaffer, the store's vice president.
"I'm just trying to stay one step ahead," said Caroline Pinkin as she rushed into the store Wednesday. "I'm picking up things I don't have to cook in case the power goes out."
Nearby at North Charles Fine Wine & Spirits, people were stocking up on "warm drinks" such as red wine, bourbon and whisky, said Robert Chapman, the store's manager.
Some hardware stores in the Baltimore area reported a shortage in rock salt, which people also sought.
While many were prepared to shutter themselves in their homes, the state was readying to keep roads as clear as possible, deploying about 2,700 plows and other pieces of snow removal equipment through the State Highway Administration and private contractors, O'Malley said.
Baltimore Mayor Stephanie Rawlings-Blake said the city planned to take advantage of on-call contracts it established with road crews "that can help us attack the residential streets at the same time our equipment is doing the primary and secondary roads."
"We haven't done all the analysis, but what we're hearing anecdotally is they're seeing a big difference," Rawlings-Blake said of plowing so far this winter. Baltimore city health officials extended a "code blue" advisory through Thursday, freeing up more shelter space and resources for the homeless.
In Annapolis, residents were encouraged to park their cars for free in city-owned garages to keep the historic city's narrow roadways clear for plowing crews. Residents could get snow vouchers by showing proof of residency to garage staff.
Baltimore County officials asked residents to keep vehicles off the street and in driveways, if possible, to allow snow plows to do their job, while in Howard County, officials planned to close Ellicott City's Main Street for snow removal.
Despite salt shortages in some parts of the country, local jurisdictions and state officials said they had plenty to treat roads, though many already spent more this season on plowing and treatment than budgeted.
Howard County has exceeded its $1.2 million budget for snowstorms this fiscal year, county spokesperson Mark Miller said. Before Sunday's snow, he said, the county had spent $2.4 million cumulatively on weather incidents — double what was budgeted — but had a $2 million natural-disaster contingency fund to fall back on.
Baltimore County officials also said they had sufficient salt, and Rawlings-Blake said the city's stores were at 85 percent of capacity.
The State Highway Administration has exceeded both its snow removal budget of $46 million and its normal annual spending of $70 million, spokeswoman Valerie Burnette Edgar said. The agency typically asks the General Assembly to make up the difference, though it has sought to gradually increase the budget each year, she said. The agency has used 319,000 tons of salt so far this winter and had about 250,000 tons on hand for use Wednesday and Thursday.
The storm snarled air traffic Wednesday, with a coating of ice and snow across the Southeast leading to more than 3,500 cancellations and 2,000 delays across the country, according to FlightAware.com. About 100 flights to and from Baltimore-Washington International Thurgood Marshall Airport were canceled Wednesday, with nearly 50 delayed.
More than 75 flights scheduled to and from BWI on Thursday were canceled Wednesday afternoon.
The storm forecast disrupted what was scheduled to be the election season's first forum of gubernatorial candidates in Maryland. Organizers canceled an event that had been scheduled for 7 p.m. Thursday at Israel Baptist Church in East Baltimore. Democratic candidates Lt. Gov. Anthony G. Brown, Attorney General Douglas F. Gansler and Del. Heather R. Mizeur and Republican candidate Charles Lollar had been expected to attend.
It remained to be seen how Thursday's snow will stack up against historic storms, but it comes at a time of year close to he anniversaries of many memorable snowfalls.
More than 21 inches of snow fell for three days starting Feb. 12, 1899, in what became known as the Valentine's Day Storm. Mail service and rail travel came to a standstill in what was the "worst blizzard ever known here," The Baltimore Sun reported at the time.
The National Guard was mobilized when 22.8 inches of snow fell Feb. 11, 1983, amid gale-force winds. That storm ranks as the second-highest single-day snowfall on record here.
The "Snowmageddon" of 2010 was capped off with a 15.5-inch snowfall on Feb. 10, for a total of nearly 45 inches of snow in six days.
Some melting of Thursday's snow is expected Friday, with highs forecast around 40 degrees and partly cloudy skies during the day before a chance of light snow in the evening. But then a cold weekend is ahead, with lows dropping back to the teens Saturday and possibly single digits Sunday, and highs in the mid-30s.