Friday, February 8, 2013

Northeast Blizzard

Yesterday, a chilly rain fell across Missouri on the south side of a winter storm that was centered over eastern Iowa; north of that central low, snow was falling across the Great Lakes region.  Meanwhile, a second, stronger storm was spinning over southwest Georgia, dragging in copious moisture from the Gulf of Mexico and igniting thunderstorms across the Southeast.

By noon today, these storms are forecast to merge along the Mid-Atlantic Coast, producing a potent winter storm system that will move to the northeast, producing heavy snow throughout New England and blizzard conditions along the Northeast Coast, from New York to Maine.  Storm surge is expected to be severe in Massachusetts and snowfall totals may exceed two feet throughout the eastern half of New England as well as in the mountains of Vermont, New Hampshire and Maine.  Good news for the ski resorts but a nightmare for the larger cities and their transportation hubs.

Potent Nor'Easters tend to occur in late autumn and early spring when an unstable jet stream favors the clash of cold, dry and warm, humid air masses.  Counterclockwise winds, whipping around the central low, pull in Atlantic moisture and force it above cold air at the surface, unleashing heavy snowfall.  These same winds, strongest near the center of the storm, combine with the intense snow to produce blizzard conditions and shove ocean water toward the coast, spawning a destructive storm surge.  The peak of the storm should occur from late this evening into the morning hours on Saturday before the system moves out to sea.