Snow followed by a wave of frigid air is plodding eastward, bringing warnings well ahead of time for people to take precautions to stay warm. The storm snarled traffic across much of the country and is threatening to bring wind chills into the single digits even to the Deep South over the next few days.
Here's a look at how the winter weather plaguing almost two-thirds of the country is playing out. (It turns out, even Hawaii isn't immune.)
SHOVELING AND SHIVERING IN MIDWEST, PLAINS
Just this past weekend, Ohio residents walked around in light jackets, enjoying temperatures in the 50s. Now, they and their neighbors across the Great Lakes are bundling up as frigid air follows several inches of snow.
Actual air temperatures in Ohio are expected to follow the example of Monday's single-digit wind chills — a calculation of how cold the air feels to exposed skin when wind is factored in — later in the week.
Illinois has it even worse. Wind chills as low as minus 30 are forecast to move in behind the storm, which dropped as much as 6 inches of snow on parts of the state. It was still snowing in parts of northeast Ohio along Lake Erie, where as much as 20 inches could drop by Wednesday night.
The snow snarled travel throughout the region Monday and Tuesday. More than 130 flights in and out of Chicago's two airports were canceled. Many school districts delayed or canceled classes, including in Columbus, Ohio's largest city. School delays and traffic accidents plagued part of Indiana. Traffic crashes in Michigan killed at least five people.
The cold put wheat crops in danger in parts of Nebraska, Iowa, Missouri, Illinois, Indiana, Ohio and Kansas. The few inches of snow that fell in the Dakotas — well used to snow and cold — nonetheless caused crashes and closed dozens of schools. In Sioux Falls, even outdoor ice-skating rinks closed Monday.
Al-Joe's Pet and Garden Center in Hamilton, Ohio, has been selling more bedding for outside dogs and cats and receiving more calls for snow removal, owner Gary Grollmus said.
"They want to get it off before it turns into a solid sheet of ice," he said.
CHAOS IN THE CAPITAL
More snow and colder-than-expected weather surprised officials and residents in and around the nation's capital, leading to frustrating commutes, air cancellations and apologies from school districts that had decided — unwisely — to remain open.
A couple of inches of snow that hit just before Tuesday's rush hour created difficulties for school buses. Twitter users roundly panned decisions by Fairfax and Loudoun, Virginia, county schools to stay open.
The hashtags #closeFCPS and #Wayde — a reference to school system spokesman Wayde Byard, who delivers the news when closures are implemented — made the worldwide list of trending topics.
Later Tuesday, Fairfax, Loudoun, Prince William and Arlington county schools apologized to parents for the difficulties. They said they decided to open using the best information available to them in the early morning.
Maryland reported dozens of accidents, including one that put a 17-year-old girl in critical condition. More than two dozen flights were canceled at Reagan National Airport.
The day was expected to bring 4 inches of snow to parts of the area. Federal officers remained open, but workers had the option to telecommute or take unscheduled leave.
MEANWHILE, IN THE S-S-SOUTH ...
The coldest weather in about a year is expected to reach deep into Georgia by early Thursday. In metro Atlanta, famously brought to a standstill last winter by a few inches of snow, wind chills below 5 degrees are expected (but no snow is forecast). Even in Cordele in south Georgia, the wind chill could hit 8 degrees.
Atlanta officials say they'll open an emergency warming center that can hold 100 people. In north Alabama, gusty winds could make temperatures in the single digits feel like it's below zero.
NORTHEAST BRACES FOR THE WAVE
In the nation's largest city, where people can go years without meeting their neighbors, the mayor is reminding residents to keep an eye out for those who might be at risk. That includes neighbors, relatives and the homeless.
Ahead of temperatures expected to drop to 9 degrees Wednesday night, with a wind chill as low as minus 15, New York Mayor Bill de Blasio made that request and also asked service providers to check on their clients. Next door in New Jersey, wind chills as low as 20 below are expected into Thursday morning.
Snow fell Tuesday on dignitaries attending the Manhattan funeral of former Gov. Mario Cuomo.
Nearby in Connecticut, officials urged people needing shelter to call a 211 hotline. And to the north in New Hampshire, with wind chills forecast to dip below minus 30 on Wednesday night into Thursday, emergency authorities told people they should stay indoors as much as possible and dress in layers if they had to go outside.
Authorities also warned about the perennial cautions needed for alternate heating sources, such as fireplaces, wood stoves and space heaters, making sure to check any cords for fraying and not place heaters too close to flammable materials. Pipes should be wrapped in insulation or old newspapers to avert freezing and bursting.
FEEL SORRY FOR HAWAII?
The Aloha State is recovering from some record-setting ... we'll call it "cold."
A low temperature of 57 degrees was reported Monday morning at Honolulu Airport, breaking the previous record of 58 for that date, set in 1893. The low temperature of 59 in Hilo on Sunday broke the record of 60 set for that date in 1999. And a low of 57 degrees at the Lihue Airport on Kauai on Monday tied a record set in 1993.
A new cold front moved across the islands Tuesday, keeping temperatures in the low- to mid-60s in most areas.