December 23, 2010
There’s only a little more clarity this Thursday morning about the prospects for significant snowfall in Central Maryland this weekend.
Although AccuWeather.com blogger Henry Margusity (map at left) – almost always at the extremes on these things – is already predicting snow totals, more mainstream forecasters aren’t ready to go that far out on a limb.
The National Weather Service forecast office in Sterling, Va. has added 30 percent chances for snow on Christmas Day and Saturday night as a weak storm system drops through the area from the northwest. Those chances then rise to 50 percent on Sunday and 40 percent on Monday as a bigger, more powerful system moves out of the Gulf and up the East Coast.
But there’s still an exasperating uncertainty in their morning discussion about the intensity and track of that bigger storm:
“GUIDANCE STILL NOT IN CONSENSUS WITH EVOLUTION OF THIS COASTAL LOW PRESSURE…IN INTENSITY OR TRACK…THOUGH SPREAD OF SOLUTIONS HAS NARROWED A BIT OVER LAST 12 HRS.
“IF THE TRACK OF SYSTEM REMAINS FAR ENUF OFFSHORE…CLOSER TO GFS [MODEL] FORECAST…THE CWA [FORECAST AREA] MAY STILL [SEE] LITTLE IMPACT ASIDE FROM INCREASING NORTHERLY WINDS SUN/MON.
“HOWEVER…IF THE TRACK IS CLOSER TO THE COAST…AS INDICATED BY THE ECMWF [MODEL]…WHICH ALSO PAINTS A SLOWER MOVING AND STRONGER LOW PRESSURE SYSTEM DUE TO THE AFOREMENTIONED PHASING…SIGNIFICANT SNOW ACCUMULATIONS COULD RESULT. AT THE MOMENT…FORECAST IS HIGHLY UNCERTAIN…”
Over at AccuWeather.com, the regular forecasters are beginning to go with a more southern storm, with snow in places like Birmingham, Atlanta and Charlotte. But that doesn’t yet get us off the hook:
“The storm appears as though it will be stronger and farther south upon crossing the middle of the nation. While this probably means snow for part of Dixie on Christmas, it could lead to a wrapped-up storm heading northward along the Atlantic Seaboard in the Sunday-to-Monday period.”
More immediately, Marylanders should be prepared today – Thursday – for persistent cold temperatures and stiff winds gusting out of the northwest at 40 mph – and more in the mountain highlands. Wind chills today will sink into the 20s or less, with a chance for flurries in northern sections of Baltimore and Harford counties.