It looks quite likely now that Central Maryland will see accumulating snow on Tuesday. Forecasters out at Sterling give it a 90-percent chance. They still aren't able to settle on accumulations, but they are leaning toward a scenario that would drop less than 6 inches on the region. Maybe just an inch or two.
And while that doesn't sound like much after living through the winter of 2009-2010, it would be the first significant storm of this season, and it would begin in time to complicate the morning rush hour. And, given what happened last week when we had less than an inch, it would likely affect school openings across the region.
The NWS is watching as low pressure in the Gulf of Mexico makes its way toward the South Carolina coast. Complicating the forecast is the progress of another low developing to our west. Sterling does not believe the two will merge, or "phase," until they have gone by to our north and east. That would limit the snowfall here:
"IF THIS SCENARIO HOLDS TRUE...THE MID-ATLANTIC...AND IN
PARTICULAR OUR CWA [FORECAST AREA]...WILL REMAIN SANDWICHED BETWEEN THE TWO SYSTEMS AND EXPERIENCE LIGHT THOUGH ACCUMULATING SNOW FOR MAJORITY OF EVENT.
"USING ALL AVAILABLE MODEL GUIDANCE...QUITE CHALLENGING TO FIND A SINGLE
MEMBER RUN THAT PROJECTS MORE THAN 6 INCHES IN THE CWA. SEVERAL MODELS SUGGEST MIX/CHANGE TO [SLEET OR FREEZING RAIN] ACROSS SOUTHEASTERN ZONES...SO HAVE
INCLUDED [WINTRY] MIX FOR LOWER SOUTHERN MD TUE AFTERNOON.
"BY LATE TUES...LOW PRESSURE EXPECTED TO PASS DELMARVA AND QUICKLY BECOME DOMINANT
SURFACE CYCLONE TUES NIGHT...RAPIDLY STRENGTHENING. DRY SLOT SHOULD ERODE
PRECIP FROM SW-NE DURING THE NIGHT...THO WILL HAVE TO WATCH FOR SOME
WRAP-AROUND MOISTURE/PIVOTING OF BANDING BACK TOWARD NE MD. ALSO...UPSLOPE SNOW SHOULD INCREASE TUES NOGHT ACROSS WEST-FACING SLOPES OF ALLEGHENY HIGHLANDS...WHICH MAY CONTINUE ... SEVERAL DAYS."
AccuWeather.com is saying the storm could be disruptive, especially if the track of the coastal low stays a few miles closer to the coast (map, left):
"Plenty of cold air will remain in place across the Northeast following the latest rounds of snow, laying the groundworks for a few to several inches of snowfall for the major Northeast cities if the next storm hugs the coastline Tuesday into Wednesday.
"Travel disruptions both on the ground and in the air are possible, as well as school and activity delays and cancellations."
The Weather Channel is focusing on the snow and ice across the Deep South this weekend. By Tuesday, their forecasters say, the coastal low will move offshore, and the western storm will move into the picture. But they don't seem much concerned with the impacts here:
"Tuesday, a separate storm producing snow in the Midwest and the storm heading up the East Coast will begin to merge. Snow will develop across the Mid-Atlantic. The storm will rapidly strengthen as it heads from off the Mid-Atlantic Coast to off the New England coast Tuesday night and Wednesday. Heavy wind-driven snow is possible across eastern New York and New England with some foot or greater accumulations possible."