The winter storm headed for the Northeast early Thursday could bring 3 to 7 more inches of snow to Baltimore, capping a winter in which a few more inches hardly seems to matter anymore.
But this one will be different - one of the most complicated and unusual winter storms we've seen in quite a while. Maryland remains mostly on the southern and western fringes of the blast, which is expected to pound portions of New York and New England with heavy snow, tropical-storm-force winds and flooding. Philadelphians were told Wednesday to expect 8 to 12 inches. New York City could receive 7 to 13 inches, while Binghamton, in south-central New York State, could see as much as 12 to 18 inches.
Forecasters expect the tempest will drift up the coast Thursday, intensify, head inland into southern New York State, then turn west onto some kind of bizarre meteorological cloverleaf, moving west, then south into Pennsylvania, then east again before it finally heads out to sea off the New England coast this weekend.
Along the way it looks like the storm will offer Baltimore rain; a rain/snow mix; then snow; then a lull in the action for a time Thursday afternoon; then more snow into Friday with a big helping of high winds.
For BWI-Marshall, the National Weather Service is calling for the storm to begin late Wednesday evening as rain and snow, turning to all snow after midnight as temperatures drop to freezing. Overnight accumulations could reach 1 to 3 inches of wet snow.
Winter Storm Watches, which mean 5 inches or more are possible by Friday morning, remained posted for Carroll, Baltimore, Harford countries, and Baltimore City. Farther south and west they were replaced Wednesday with Winter Weather Advisories, calling for 3 inches or less during the first phase of the storm.
After daybreak Thursday, the snow is forecast to continue until around 1 p.m., then quit for a time. That's the lull.
The break occurs as the storm intensifies off the coast, and drags dry air in from the southwest, cutting off the
precipitation for much of the region. Portions in the mountains, the western shore of the bay and extreme northern Maryland may be slower to dry out, forecasters said.
Forecasters then expect the winds here will shift to the northwest and increase in speed, pulling colder air down from Canada around the west side of the low, which spins counter-clockwise. The highest winds will occur overnight Thursday into Friday, reaching 15 to 25 mph with gusts to 35 mph.
The high winds, saturated soils and heavy, wet snow may lead to more downed libs and trees, and power outages, forecasters warned.
As the low moves into New York State, and begins to pivot to the west, then south into Central Pennsylvania, it is expected to trigger the third phase of the storm. The weather service says it will drive more snow into Maryland. Two to 5 more inches are possible at BWI before it all ends early Friday morning, according to the weather service.
"Considering the longevity of this system across the area, this period could possibly have the heaviest snows and highest accumulations for the Baltimore metro area and points northeast," said forecasters at AccuWeather.com. "Back into the DC Metro area and points northwest and southeast, lesser amounts expected, especially with wind-driven snow overnight and localized bands that may also be fairly short-lived."
Complicated enough? There's more. The blustery weather could continue through the weekend, with chances for light snow showers as a parting shot.
Eric the Red, a professional meteorologist in Baltimore, says:
"This is a very low confidence forecast, because the heavy snow will be just to our east and northeast, and any slight wobble could well result in blizzard conditions. My best early guess: Northern Va./D.C.: 1-2", perhaps less; Central Maryland: 2-4"; Northern Maryland: 3-6", perhaps as much as 8 inches."
Later, he said the potential for his forecast to "bust" was high:
"I'd place my money on the snow being less than advertised. The current 40-degree temperatures don't help either."
(SUN PHOTO/Amy Davis, March 2009)