A late-season storm was forecast to bring the first significant snowfall in Baltimore in two years Wednesday, prompting worries about travel difficulties and power outages from the wet, heavy flakes and strong wind.
The National Weather Service forecasts snowfall of 6 to 12 inches north and west of Interstate 95, though a rain mix along the I-95 corridor could reduce accumulations. The storm, which dumped nearly a foot of snow on the northern Plains states, could bring intense bands of heavier precipitation in some areas, forecasters warned.
Emergency responders and utility crews were mustering resources, officials urged residents to stay off roads and check on elderly neighbors, school closings were being considered and crews were hurrying to pre-treat roads. Baltimore Gas and Electric Co. was preparing for the possibility of "several hundred thousand" outages.
Regardless of how the storm compares with expectations, it wouldn't take much to surpass the recent winters, which have paled in comparison to the memorable "Snowmageddon" winter of 2009-2010. The predicted accumulation would likely at least double the region's snowfall total this winter, with spring not far off.
"I always hate to say it, but this is probably winter's last gasp," said Steve Zubrick, science and operations officer for the weather service's Baltimore-Washington forecast office in Sterling, Va.
Precipitation was expected to start as rain or a wintry mix late Tuesday, turning to snow in most of the area by early Wednesday. There was a chance that rain could mix in, with the divide between frozen and liquid precipitation difficult for forecasters to place.
"Baltimore, kind of like D.C., they're kind of right on the edge of getting rain and snow during the day," Zubrick said. "It's just so close."
But heavy snow was considered almost a certainty farther north and west. For Frederick County and points west in Maryland, 10 to 14 inches was expected. The heaviest snowfall is likely along Virginia's Blue Ridge Mountains, where up to a foot and a half is possible, according to the weather service.
At least two deaths have been tied to the storm, when a semi-trailer flipped off a highway bridge and sank in a Wisconsin river. Winter storm warnings were in effect Tuesday for all or parts of 16 states, including most of Maryland, from the upper Midwest to the Mid-Atlantic.
The snow is expected to be wet and heavy, which could weigh down trees and roofs. With highs Wednesday expected to reach slightly above freezing, relatively warm air near the ground can help make flakes thicken and clump together, Zubrick said. Snow can accumulate despite warm surface temperatures if the air aloft is cold enough and precipitation intense enough, he said.
Winds were expected to be blustery, 15 to 25 mph with gusts of 35 mph or more through the day Wednesday.
BGE was mustering 1,500 utility employees and 650 out-of-state workers. Utility officials use storm experiences and predictive algorithms to estimate the magnitude of outages a storm might cause, said BGE spokeswoman Rachael Lighty.
"We can plan as much as we want, but the weather is crazy and it can change at any minute," Lighty said. "We do the best we can, but we definitely hope for the best-case scenario but make sure we're prepared for the worst."
For many in Maryland, memories of lengthy storm-related outages are fresh. A derecho in June left many without power for a week, and superstorm Sandy caused power grid disruptions. But utility officials said tree-trimming efforts and other upgrades could prevent some outages.
"Especially around the Towson area, we've gotten a lot of our aggressive trimming done in a lot of the areas we've experienced problems in the past," said Mike Garzon, BGE's supervisor for customer reliability support in Baltimore County. "We do believe there's going to be a significant improvement in some of these areas."
AAA Mid-Atlantic warned motorists to be aware of potentially hazardous conditions during the Wednesday morning commute . Forecasters said that while roads may be passable in the morning, the evening commute could be more difficult.
"The longer motorists can stay off the roads, the safer it will be and the faster area road crews can clear the roads. Our best advice is to just stay home if possible or take mass transit," said Christine Sarames Delise, a spokeswoman for AAA Mid-Atlantic. "If you do have to drive, understanding how to safely navigate your vehicle during this type of weather will improve your safety and reduce your risk of a crash."
Dangerous travel could prompt area schools to close. McDaniel College decided Tuesday afternoon to close its Westminster campus Wednesday. A spokeswoman for Howard County Superintendent Renee Foose said the district would announce a decision on whether to close schools by 5:30 a.m.
At Baltimore-Washington International Thurgood Marshall Airport, snow-removal crews that included airport employees and contractors were at the ready to clear runways and other surfaces. Airport officials urged travelers to check with airlines before heading to the airport Wednesday, warning of the possibility of delays or cancellations.
About three dozen flights to and from BWI had been canceled by Tuesday evening as the storm approached, according to airline statistics website FlightAware.com.
Road crews were preparing for their first major challenge of the season on Maryland highways. Drivers were urged to stay at least five car lengths behind plows.
"After numerous squalls with minimal snow accumulation in the metropolitan areas, many drivers may have become complacent in preparing for driving in winter weather," said state highway administrator Melinda B. Peters. "If predictions are correct, everyone will need to be alert and prepared."
This winter, 4.8 inches of snow have fallen at BWI, compared with 18 to 20 inches in a typical winter.
Any snow that accumulates isn't expected to stick around for long. Temperatures were forecast to reach highs in the 40s after the storm and into the 50s by early next week.
Reuters and Baltimore Sun Media Group reporters Jon Meoli and Luke Lavoie contributed to this article.