Travelers, beware! A wintry storm advancing toward the Northeast region is expected to cause icy, dicey conditions from Wednesday evening into midday Thursday as temperatures nosedive and rain turns to freezing rain, sleet and then snow.

North and Central Berkshire areas could see 4 to 8 inches of heavy, wet snow on the ground by dawn Thursday, according to the National Weather Service's mid-morning update. South Berkshire is targeted for only 1 to 4 inches because the changeover to a wintry mix is unlikely before late evening.

The government forecasters issued a winter weather advisory for Berkshire County, in effect from 6 p.m. Wednesday to 11 a.m. Thursday. But areas to the north -- all of Vermont and much of upstate New York -- are under a winter storm warning with 10 to 20 inches of snowfall expected.

After Tuesday's taste of spring, with a high of 49 at Pittsfield Municipal Airport, the return of winter with only eight days until the vernal equinox will come as an unwelcome reminder that March is a stormy month in the Berkshires, with a long-term snowfall total of13 inches by April Fool's Day.

The hazardous brew of rain, then ice and snow -- with a flash freeze caused by a sharp temperature drop from the 30s into the teens or lower overnight -- is the result of an intensifying winter storm that was over Pittsburgh at midday on Wednesday, tracking toward New York City, Long Island and, by Thursday noon, heading out to sea off Cape Cod.

Rain, which could become heavy on Wednesday afternoon, is set to transition to a mix of sleet and freezing rain shortly before dark, followed by a changeover to all snow by midnight, then tapering off before dawn on Thursday, according to meteorologist Brian Frugis of the National Weather Service in Albany, N.Y.

The greatest hazard is likely to be a flash freeze as temperatures skid Wednesday evening, causing roads and sidewalks to ice over as colder air rushes in, Frugis pointed out. Travel will be hazardous, and the snow will make matters worse. Northerly winds will pick up to 15 to 25 mph, with gusts up to 35 mph possible.

"The evening commute looks to be significantly impacted as falling temperatures and changing precipitation types make for hazardous travel across the region," Frugis said. Once the transition is completed, snowfall rates could reach one inch per hour at times, with a quick accumulation and rapid freeze up.

It will feel like mid-winter from Thursday through Sunday, with lows from zero to 10 before first light on Friday as strong winds continue. Forecasts through Tuesday call for well below normal temperatures, but the next major storm is expected to stay south of Western Massachusetts on Monday, based on current computer models.

To contact Clarence Fanto:

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