I’ve been tweeting about this since last night, but it’s not just Minnesota that’s getting record cold temperatures today.  A “polar vortex” has settled over the upper Midwest, but the wind chill warnings extend all the way down to Florida. Don’t let the chatty intro to this video fool you — this is a dangerous cold front that could kill people who don’t take it seriously enough:

A whirlpool of frigid, dense air known as a “polar vortex” descended Monday into much of the U.S., pummeling parts of the country with a dangerous cold that could break decades-old records with wind chill warnings stretching from Montana to Alabama.

For a big chunk of the Midwest, the subzero temperatures were moving in behind another winter wallop: more than a foot of snow and high winds that made traveling treacherous. Officials closed schools in cities including Chicago, St. Louis and Milwaukee and warned residents to stay indoors and avoid the frigid cold altogether.

The forecast is extreme: 32 below zero in Fargo, N.D.; minus 21 in Madison, Wis.; and 15 below zero in Minneapolis, 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.

“It’s just a dangerous cold,” said National Weather Service meteorologist Butch Dye in Missouri.

It hasn’t been this cold for almost two decades in many parts of the country. Frostbite and hypothermia can set in quickly at 15 to 30 below zero.

As I write this, the temperature outside my door is -24, and the wind chill would make it seem like -45 … if I was dumb enough to go outside. It never got above zero yesterday, but I still went to church and did some shopping, knowing I wouldn’t get an opportunity to do either for the next couple of days. The weather service has a wind-chill warning up here in effect until late Tuesday, and we’re not expected to see above-zero temps until Wednesday.

Fox News has a little more:

The forecast is extreme: 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. Northeastern Montana was warned of wind chills up to 59 below zero.

“It’s just a dangerous cold,” said National Weather Service meteorologist Butch Dye in Missouri.

Several Midwestern states received up to a foot of new snow Sunday. Five to 9 inches fell in the Chicago area by Sunday afternoon, St. Louis area had about a foot of snow and northern Indiana had at least 8 inches. Central Illinois braced for 8 to 10 inches, and southern Michigan could see up to 15 inches.

Officials closed several Illinois roadways because of drifting snow and warned residents to stay inside. Roads in the Midwest were particularly dangerous, and officials in Missouri said it was too cold for rock salt to be very effective.

NBC did a segment on the bitter weather this morning as well:

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Threatening not just records but lives, a blast of arctic air packing the lowest temperatures in two decades descended on the Midwest on Monday and began a brutal plunge across most of the United States.

People in Minnesota and the Dakotas woke up to temperatures of 20 degrees below zero or worse, and the National Weather Service said that it recorded a wind chill of minus 61 in Montana.

“These temperatures that will be out there will be lower than what’s in your freezer,” warned Greg Ballard, the mayor of Indianapolis.

Actually, it’s far below what you’ll find in your freezer here. I have been using the garage as a “stunt freezer,” since our kitchen freezer is a little overloaded at the moment, and the stunt freezer is working perfectly.

What are your stories of the cold? Share them in the comments below.

Update: Schools are closing tomorrow, too, at least in the Twin Cities:

In a letter to districts, the education commissioner says superintendents should be mindful about health hazards from exposures to the below-zero temperatures as they make decisions.

Monday was the first blanket closure of all public schools in 17 years as the state is gripped with an arctic blast of cold air.

So far, Minneapolis, St. Paul and Roseville announced schools will remain closed on Tuesday.

Today’s closure was ordered by Gov. Mark Dayton, but I suspect we’ll see a statewide closure again tomorrow, just district by district this time.