An Arctic outbreak even more extreme than one felt in early September is expected to race southeastward from the northern Rockies Friday night to the southern Plains by next Monday that could deliver temperature departures from average of 30-40 degrees Fahrenheit.
The air is forecast to be so cold at its peak as to bring nighttime low temperatures to within a few degrees of zero in parts of Idaho, much of Montana and Wyoming, as well as the western parts of the Dakotas and northern Colorado.
For example, “in Billings, Montana, the temperature is forecast to shatter the current record of 18 set in 1997 Saturday night by at least 14 degrees and to blow away the record low of 22 set in 2002 on Sunday night by 22 degrees,” according to AccuWeather Meteorologist Reneé Duff.
Record-challenging cold will be felt as far south as New Mexico, Kansas, Oklahoma and Texas by early next week, where temperatures are forecast to dip into the teens and 20s at night.
Heavy snow, on the order of a foot or so, is most likely over the north- and east-facing ridges and peaks from Washington on Friday to northern Idaho and Montana on Saturday, Colorado on Sunday and northern New Mexico on Monday as the cold air pours in.
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