The National Weather Service has posted a winter storm watch for Saturday for all of Western Maryland, and for the northern tier of counties, including Carroll, Frederick, Harford and northern Baltimore County.
The watch called for the "potential" of 5 or more inches of snow in portions of the state on Saturday, beginning overnight Friday as rain, then changing to snow Saturday morning and continuing through Saturday afternoon.
The weather service predicted a small pocket of 6-inch accumulations in extreme northwestern Carroll and northeastern Frederick, surrounded by gradually diminishing totals of 4-, 2- and 1-inch totals. For Baltimore and its immediate suburbs, they're looking for less than an inch. And to the south and east of Interstate 95, there's just rain.
The snowiest day on record for Baltimore in October came on Oct. 30, 1925, when 2.5 inches fell. Since official record-keeping began, measurable snow has fallen on Baltimore on only four October days.
An inch of snow at Baltimore-Washington International Thurgood Marshall Airport could make this the second-snowiest October day on record for Baltimore.
AccuWeather.com says the storm could deliver as much as 6 to 12 inches from western Virginia and Maryland to central New England.
Jeff Halverson, an associate professor of meteorology at University of Maryland, Baltimore County, says he believes the storm's "bull's eye" will be just north of the Mason-Dixon Line, running across eastern Pennsylvania into northern New Jersey.
"This will likely be a very wet, dense snow," he said. "Because so many trees still bear foliage, there is the potential for unprecedented, widespread power outages and temporary closure of major interstates such as I-78."