National Weather Service forecasters have boosted their estimate of our chances for more accumulating snow Saturday night into Sunday. The risk climbed this evening from a "slight" - 20 pct - chance, to 50 percent. Here's a slice of this evening's forecast discussion from NWS Sterling:

"AN UPPER-LEVEL DISTURBANCE WILL PASS THROUGH THE TENNESSEE AND
MISSISSIPPI VALLEYS SATURDAY BEFORE APPROACHING THE SOUTHEAST COAST
SATURDAY NIGHT. AS THE UPPER-LEVEL DISTURBANCE INTERACTS WITH THE
BAROCLINIC ZONE ALONG THE SOUTHEAST COAST...LOW PRESSURE IS EXPECTED
TO DEVELOP. LOW PRESSURE WILL MOVE UP THE MID-ATLANTIC COAST SUNDAY
AND TOWARD NEW ENGLAND SUNDAY NIGHT.

"THE TRACK OF THIS SYSTEM WILL HAVE A SIGNIFICANT IMPACT ON OUR
FORECAST SATURDAY NIGHT AND SUNDAY. IF THE SYSTEM HOLDS CLOSER TO
THE COAST...THERE WILL BE ACCUMULATING SNOW ACROSS MOST OF THE AREA.

"IF THE SYSTEM MOVES FURTHER OUT TO SEA...ACCUMULATING SNOW WILL BE
MAINLY TO OUR EAST. THERE IS STILL A GOOD DEAL OF UNCERTAINTY AS TO
EXACTLY WHAT SCENARIO WILL PLAY OUT...BUT LATEST GUIDANCE HAS
SUGGESTED THAT THE LOW MAY BE CLOSER TO THE COAST."

Heh heh. Snow.

Foot's Forecast doesn't have much more than this to offer yet on this storm.  AccuWeather.com is leaning more toward a Delmarva event (map, above) as the storm bears right out in the Atlantic:

"The latest consensus among AccuWeather.com meteorologists is the storm will graze the eastern mid-Atlantic with accumulating snow, while the full fury of the storm could be unleashed over New England and neighboring Canada. This is by no means the final word on the storm, but rather our best shot at this early stage. Updates on the storm will follow on AccuWeather.com

"With a track well off the coast Saturday night and Sunday, it appears to be unlikely "heavy" snow will reach the I-95 mid-Atlantic and the northern and western suburbs from Washington, D.C. to Philadelphia."