It was clear yesterday morning where the boundary fell in our metropolitan area between the areas that got moderately significant early season snowfall and those that got little or none. It was Falls Road, the two-lane arterial road between Potomac and Rockville.

East of Falls Road as far as the Beltway near Montgomery Mall, there was a light dusting of the white stuff that looked more like frost than snow. As one drove west, the whiteness increased. But when one got to the top of the hill on Tuckerman Lane and reached Falls Road, the view to the west was quite solidly white -- a landscape of the season that is traditional across the northern reaches of our nation. (For me, it ain't at all traditional: my own first real snowfall was experienced at age 19.)

A meteorologist I'm not, but a longtime Washington reporter I am -- and such a division on a generally southwest-northeast line in this metropolitan area is nothing new. Snow, heavy rain and tornadoes tend to be sluiced across that route parallel to the eastern slopes of the Blue Ridge, hitting Leesburg, Herndon, occasionally Fairfax City, then Potomac and Gaithersburg; but often missing, or skimping on, Washington itself.