The Berkshires continue to ride a roller coaster of winter weather as the region plunges into another deep freeze, following a one-day warm-up.
A whirlpool of frigid, dense air known as a "polar vortex" was expected to suppress temperatures in more than half of the continental U.S. starting today, with wind chill warnings stretching from Montana to Alabama, according to forecasters.
Locally, the second arctic air mass in less than a week will settle in on Tuesday, resulting in 30-degree difference compared to this afternoon's temperatures, according to the National Weather Service office in Albany, N.Y.
"Highs could be in the low 40s, gradually dropping through 20s," said NWS meteorologist Luigi Meccariello. "Sometime after midnight, they will fall into the teens with temperatures 8-10 degrees by daybreak [on Tuesday]."
Meccariello said subzero lows will be felt overnight Tuesday, with a gradual warming trend to nearly 30 degrees by the end of the week.
The Berkshires will be mild compared to the central part of the country, parts of which expected to be as cold as 30 degress below zero overnight Sunday, with a wind chill approaching dangerous levels of 60 below.
The forecast was extreme by daybreak today: 25 below zero in Fargo, N.D., minus 31 in International Falls, Minn., and minus 15 in Indianapolis and Chicago. Wind chills -- what it feels like outside when high winds are factored into the temperature -- could drop into the minus 50s and 60s.
Ahead of the bitter cold was a winter storm that brought up to a foot of snow to several Midwestern states. From Missouri to southern Michigan, 5-12 inches of the white stuff fell on Sunday, with major cities like St. Louis and Chicago in the 8-10 inch range. However, the same low pressure system tracked north and west of the Berkshires, allowing warm air to override the colder air at the surface, creating an icy mix of sleet and freezing rain overnight Sunday, according to forecasters. The National Weather Service had posted a winter weather advisory until 6 a.m. today.
"By the time of the [Monday] morning commute, we expect all liquid precipitation," noted Meccariello.
He added that the rain was expected to change to snow before ending this evening.
To reach Dick Lindsay:
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