(CNN) -- A bitter mass of cold air extended its grip across much of the United States early Friday morning. The upper Midwest, Ohio Valley, New England and even the Southeast suffered under dangerous temperatures and brisk winds.
A thermometer registers minus 20 degrees Thursday in Hudson, Wisconsin.
In Minneapolis, Minnesota, it was minus 17 degrees early Friday, and the forecast high was only 8 degrees, CNN affiliate KARE reported.
Minnesotans are famous for embracing frigid weather, but this wave even has them staying indoors. A couple hundred schools around Minneapolis either called off classes all together or started late Thursday, KARE said.
The arctic blast caused pipes to bust in St. Louis, Missouri, CNN affiliate KPLR said. Friday's high is expected to reach 18 degrees.
A wind-chill advisory is in effect in Pittsburgh, Pennsylvania, CNN affiliate WPXI said. It was minus 2 degrees early Friday, and with the wind, it felt like minus 20, WPXI said. Watch how people are dealing with the cold »
The cold snap has gripped the United States for days. It was brutal in Ames, Iowa, on Wednesday.
"Last night, the temperature was still above zero (3 degrees Fahrenheit), but the wind chill (minus 14 degrees) was cold enough to make your skin burn," iReporter Kevin Cavallin said.
"When it gets this cold, your hands are just in pain when doing something as simple as carrying bags of groceries from the car to the apartment." iReport.com: What's the weather like near you? Send photos, video
It was 48 below in Fargo, North Dakota, where unprotected fingers could suffer frostbite in 60 seconds, CNN meteorologist Rob Marciano said. Watch the freeze in Iowa »
The freezing temperatures are likely to remain in the East through the weekend, according to the National Weather Service. There were low teens Thursday along much of the Interstate 95 corridor, which hugs the Atlantic from Maine to Florida.
It was 17 in New York, which had a moderate snowfall Thursday that delayed flights a few hours on the ground at LaGuardia Airport.
"If you live east of the Mississippi River, the temperature at mid-morning may be the best you'll get," Marciano added.
Temperatures dipped to 19 degrees below zero in Michigan and 10 below in Chicago, Illinois. Snow caused more traffic nightmares in the Midwest.
The Southeast is not being spared this time. A cold high-pressure system is expected to remain over the area through Saturday, the National Weather Service said. Another cold front is expected to move in late Sunday.
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