One … more … day.

The Twin Cities and the rest of Minnesota are creaking through what threatens to be another twice-round-the-clock subzero experience Tuesday, with consequences mirroring Monday's.

Yes, nearly every schoolkid is home, motorists are negotiating slippery black ice conditions on the morning commute and rail service in the metro is struggling again to stay on schedule. The University of Minnesota, which closed its Twin Cities campus Monday, opted Tuesday to only call off morning classes.

Readings in the double digits below zero blanketed the Twin Cities before sunrise, according to the National Weather Service (NWS). Eden Prairie was the metro's coldest of the cold at minus 19. Tuesday's high might get to 0, the NWS is saying.

The Mall of America in Bloomington is offering families with kids who are unexpectedly home to come and enjoy the rides at Nickelodeon Universe for free until 4 p.m.

"We understand that caregivers, grandparents and others have been called upon to help with these unscheduled holidays," the mall explained in a statement, "therefore we are offering free rides as a way to say thanks."

The NWS says the weather will be warming cockles in the hearts of Twin Citians come Wednesday, when a high in the low 20s is an almost certainty. The rest of the week, however, gets chilly again, but nothing like the past few days.

Police and tow truck drivers struggled Tuesday to stay on top of the outbreak of crashes and rollovers littering metro highways. One of them proved fatal. An SUV slid off of icy I-94 on the western edge of St. Paul in a crash that killed the driver, the State Patrol said.

Traffic stacked up on northbound I-35 in Lakeville where a rollover in the median at County 50 was the first obstacle for commuters heading toward Minneapolis. A pair of rollovers at Burnsville Parkway and crashes at 94th Street and 82nd Street tangled traffic for the early portion of the morning commute.

Commuters on westbound 694 through New Brighton and Fridley shared in the pain. Wrecks at East River Road and University Avenue created back up traffic a couple of miles to Interstate 35W. A vehicle that landed on its side on the Wakota Bridge clogged traffic on westbound I-494 in Newport back into Woodbury.

Black ice coated roads, and as police cleared one crash, another one or two took its place. By 7:15 a.m., there had been no fewer than 30 crashes on main roads in the Twin Cities.

Transit riders fared better on Tuesday as buses appeared to be on time. Metro Transit said the second and final Northstar Commuter line runs inbound were about 20 minutes late.

Elsewhere in the state, Fosston in northwestern Minnesota reported 33 below (minus 52 windchill) before dawn. Moose Lake in east-central Minnesota was 31 below. Park Rapids was close behind at minus-29. Basking in relative warmth: Jackson at 8 below.

The run of school closings declared because of extreme predawn cold has inspired the more seniorly crowd that has at the ready their memories of "walking uphill both ways in the snow to school against the wind," and on and on.

Such harrumphing at present-day caution brought licensed school nurse Janelle Holmvig to counter in Tuesday's Star Tribune that "students wait [for buses] in the cold, too frequently with faces, hands, feet and ears exposed to the below-zero temperatures. As a school nurse, I know that children's bodies are more vulnerable to the dangers of frostbite and its potentially debilitating results."

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