Arctic air blast covers more than half of U.S.

With a giant blast of Arctic air covering more than half the country, it is the coldest morning of the winter for tens of millions of Americans.

The cold extends from the Northeast all the way to the Gulf Coast. Low temperatures are in the 30s all the way to Orlando, and they will be even colder Thursday.

In Nashville, where temperatures fell to around zero overnight, people are bracing for another round of snow and bitter cold, and many of them will have to do so without any power. Outages are affecting more than 59,000 customers across the state dealing with plummeting temperatures not seen in years, reports CBS affilitate WTVF's Cuthbert Langley.

Through piling snow, crews across the South are racing to clear roads that have been iced over by the blistering cold.

"It's going to turn into black ice, and you won't be able to tell where it's slick," Michael Taylor said. "I plan to be inside at that point."

In Franklin, Tennessee, several cars and trucks spun out of control trying to avoid an accident directly in front of them.

The deep freeze turned deadly after a tractor trailer struck and killed 34-year-old Kristi Clark and her 10-year-old son. They had stopped to help people in an overturned SUV.

Throughout the region, slick, snow-covered streets have made driving dangerous and resulted in at least 9 deaths.

Farther north, in Kentucky, rescue crews responded to a call for a dog that had fallen through an icy lake.

"As we were responding, we were updated there was two people now in the water, which changes the game a little bit," Jefferson County Special Operations' Kent Kruer said.

A couple had fallen into the freezing water trying to save their dog. Firefighters were able to pull them to safety, but not their pet. Nicole Young grabbed a kayak from her apartment and helped rescue the stranded animal.

"I just paddled over to the dog, grabbed her collar and then got her up on the nose of the boat," Young said.

"We had a rope attached to her kayak and once she got the dog, we pulled her in," Lyndon fire Capt. Moe Tischendorf said.

Back in Tennessee, utility crews are desperately trying to restore power for thousands as the mercury threatens to plunge to record lows.

Schools in Nashville will be closed Wednesday, as Tennessee remains under a state of emergency. There is no letup in sight from this blast of winter, as forecasters are predicting more snow later this week.

Meanwhile, all that snow and ice in the South is nothing compared to Boston. The city just hit the 8 foot mark -- 96.3 inches of snow this winter.

That is the second highest total it's ever recorded.

Mass transit officials tell commuters it'll be slow going again Wednesday morning.

According to CBS News correspondent Jericka Duncan, seven states are participating in the effort to get rid of the snow and ice that's making it difficult to drive, train and boat around the city.

A 175-foot Coast Guard ice breaker is tearing through ice up to 9 inches thick, clearing pathways so other vessels can travel in and out of Boston Harbor.

"As you can see it's difficult to maneuver in the ice, so what we're doing is trying to keep it broken up," Capt. Jesse Deery said.

He and his crew were called down from Maine.

"Heating, fueling oil, all those things that you know people use to keep warm during this time of year come in to the port. So keeping this port open is critical," Deery said.

Their job also includes making sure 7,800-pound buoys, encased in ice, remain afloat to keep passing ships away from danger. To get the snow and ice off, workers are pounding at the frozen buoys with sledgehammers.

Creating passageways is the priority on land, too, where Boston officials are urging people to shovel out their fire hydrants.

Hundreds of workers along with the help of prison inmates are chipping away at the snow covering Boston's rails lines, which have been delayed, frustrating commuters.

"The commute is horrible. Absolutely horrible," one person said.

The MBTA estimates it could take 30 days to fix the system, which Massachusetts Gov. Charlie Baker said is just too slow.

"We need to be faster than that, but I do not want anybody over promising and under delivering here," Baker said.

To give people some additional incentive to help with the cleanup, the Red Sox are handing out free game tickets to whoever digs out a fire hydrant. The offer expires Wednesday afternoon.