Yes, again -- forecast calls for up to a foot of snow

Light snow dusted much of the region today, a prelude to a bigger storm arriving Wednesday, a nor'easter that, according to forecasters, could dump 8 to 12 inches of snow on some areas of Massachusetts.

The National Weather Service warned that the coastal storm could drop more than 6 inches of snow in Western, Central, and Northeastern Massachusetts, including Boston; drop 4 to 8 inches on the Cape and islands; and drop 8 to 12 inches on Southeastern Massachusetts.

The snow is expected to begin late afternoon or early evening. On the Cape and islands, it's expected to begin as rain, then change to snow by late Wednesday night.

Forecasters warned of slippery roads on Wednesday night. In Southeastern Massachusetts and on the Cape and islands, they said, the heavy wet snow may bring down tree limbs and power lines.

The unpleasant weather news comes as the state is emerging from a bitter cold snap -- the temperature, which had dipped to 2 below zero on Sunday night, rose to 30 by midafternoon at Logan International Airport -- and with the state already far ahead of the average in terms of snowfall for the year.

Meanwhile, Accuweather.com, the private forecasting service said today that persistent cold is expected through at least the middle of February across much of the eastern part of the country. The colder-than-normal weather could break in late February, but cold and storms could return from mid- to late March into April, the service said.

The New York Times reports today that the cold weather has been caused by the weakening of a pattern of atmospheric circulation that normally keeps cold air penned farther north. The weakening has allowed tongues of cold air to move south, while warm air moves north. Continue ►