FOTOS: Se congela el centro-norte de Estados Unidos

With temperatures around minus 20 degrees, a person crosses the tracks as a late-arriving Union Pacific-Northwest Line Metra train pulls out of the station early Jan. 30, 2019, in Palatine.

A man rides the CTA Blue Line in below-zero temperatures on Jan. 30, 2019.

With temperatures around minus 20 degrees, early morning commuters board a late-arriving Union Pacific-Northwest Line Metra train early Jan. 30, 2019, in Palatine.

The Chicago skyline seen from North Avenue Beach as the sun rises on a cold and chilly morning Jan. 30, 2019.

Charles Robertson, assistant cemetery manager at All Saints Cemetery, checks a gravesite for upcoming burials on Jan. 30, 2019, in Des Plaines.

The sunrise reveals a frigid Chicago lakefront near Montrose Harbor with temperatures around minus 20 degrees early Jan. 30, 2019.

Metra Electric line commuters waiting for a train at the Flossmoor station listen to an announcement early Jan. 30, 2019, that the agency was suspending all service on the line due to problems related to extreme cold.

Metra Electric line commuters at the Flossmoor station listen to an announcement from the agency that all service is suspended on the line early Jan. 30, 2019, due to problems related to the extreme cold.

A man walks by the Picasso statue in the Loop as temperatures begin to fall below zero Jan. 29, 2019, in Chicago.

Richard Vargas of the Salvation Army and a woman from a local church pray with David Jefferson, 30, near Lower Lower Wacker Drive on Jan. 29, 2019, in Chicago. Vargas visited several locations around the city to ask anyone sleeping outside to seek shelter.

Mimi Hristova of the Salvation Army helps Tia Williams collect her things near Lower Wacker Drive before going to a warming center for the night at the Salvation Army’s Freedom Center on the 800 block of North Christiana Avenue Jan. 29, 2019, in Chicago.

Richard Vargas of the Salvation Army gives a woman food who was sleeping in a tent near a wooded area adjacent to the Dan Ryan Expressway Jan. 29, 2019, in Chicago. Vargas visited several locations around the city to ask anyone sleeping outside to seek shelter.

A bicyclist rides a Divvy along Milwaukee Avenue in negative temperatures on Jan. 30, 2019, in West Town.

A man carries a propane tank he brought to donate to people sleeping in a wooded area near the Dan Ryan Expressway on Jan. 29, 2019, in Chicago.

Stephanie Haaser, 32, gets her cot ready before going to sleep in a warming center at the Salvation Army’s Freedom Center on the 800 block of North Christiana Avenue on Jan. 29, 2019, in Chicago.

A person walks between tents while people sleep near a wooded area adjacent to the Dan Ryan Expressway on Jan. 29, 2019, in Chicago.

A woman walks a dog in circles at a park on the corner of Oak Street and East Lake Shore Drive on Jan. 29, 2019, in Chicago.

A man walks in the 600 block of North Michigan Avenue on Jan. 29, 2019, in Chicago.

A man walks through Pioneer Plaza in the 400 block of North Michigan Avenue on Jan. 29, 2019, in Chicago.

An ice breaking boat operated by the Chicago Department of Water Management cuts through the ice in the Chicago River near the DuSable Michigan Avenue Bridge as frigid temperatures persist in Chicago on Jan. 29, 2019.

Ice forms along the shoreline and around Navy Pier on Lake Michigan, Jan. 29, 2019 in Chicago.

Ice forms on Lake Michigan along Lake Shore Drive Jan. 29, 2019, in Chicago.

A woman poses for a photograph at Oak Street Beach on Jan. 29, 2019, in Chicago.

People wait for buses in the 600 block of North Michigan Avenue on Jan. 29, 2019, in Chicago.

People walk in temperatures near zero degrees as snow and wind swirl during a cold weather snap on Jan. 29, 2019 in Chicago’s Loop.

A woman’s glasses fog up while covered up in layers as the frigid temperatures continue in Chicago, Jan. 29, 2019.

Metra trains go in and out of the Western Avenue Station in subzero temperatures on Tuesday, Jan. 29, 2019 in Chicago. The tracks are heated with gas-fired switch heaters that help prevent switching problems in extreme weather.

Metra trains go in and out of the Western Avenue station in subzero temperatures on Jan. 29, 2019, in Chicago. This is the busiest station with over 300 trains passing through on weekdays.

Metra carman Diego Lopez helps bring a train car into the Western Avenue yard on Jan. 29, 2019, in Chicago. Workers here perform routine and emergency maintenance on a daily basis, including cleaning cars, replacing brakes, and refueling trains.

A pigeon warms itself up from a memorial flame at Daley Plaza as the frigid temperatures continue in Chicago, Jan. 29, 2019.

A man walks along an icy breakwater at sunrise at 31st Street Beach in Chicago on Jan. 29, 2019.

Lake Michigan waves splash against a breakwater at sunrise at 31st Street Beach in Chicago on Jan. 29, 2019.

Metra trains go in and out of the Western Avenue Station in subzero temperatures on Jan. 29, 2019, in Chicago. The tracks are heated with gas-fired switch heaters that help prevent switching problems in extreme weather. Metra spokesperson Meg Reile said, “They are like giant gas grills.”

A photographer watches the sun rise on the Chicago lakefront at North Avenue beach on Jan. 29, 2019.

A jogger runs along the lakefront with temperatures in the single digits near North Avenue beach in Chicago as the sun rises on Jan. 29, 2019.

Pedestrians cross Lake Street bridge while sheets of ice cover the Chicago River Monday Jan. 28, 2019, in Chicago.

Pedestrians contend with snow and cold weather at Clinton Street and Jackson Boulevard in Chicago on Jan. 28, 2019.

A pedestrian walks by a dress in window near the 2600 block of South Avers Avenue in the Little Village neighborhood of Chicago on Jan. 28, 2019.

A man walks along the Chicago lakefront near Montrose Harbor on a cold and snowy morning Jan. 28, 2019.

Snowplows clear snow along runways and the tarmac at Chicago O’Hare International Airport on Jan. 28, 2019. More snow is expected and temperatures are forecast to drop this week.

Kelly Nichol tosses a snowball for her 11-month-old dog Mason at the dog park at Horner Park on Jan. 28, 2019, in Chicago. In addition to the pink coat, Nichol said she puts a special cream on Mason’s paws to protect him from the cold.

A man clears snow near Western Avenue following several inches of snowfall in Chicago on Jan. 28, 2019.

Commuters await their train at the CTA’s Pink Line Damen station following several inches of snowfall in Chicago on Jan. 28, 2019.

A man shovels snow off the sidewalk after an overnight storm Jan. 28, 2019, in the Albany Park neighborhood of Chicago.

A young boy trudges through the snow with shopping bags following several inches of snowfall in Chicago on Jan. 28, 2019.

A dog plays in the snow near Montrose Harbor in Chicago on a cold and snowy morning Jan. 28, 2019.

Pedestrians walk to the CTA Montrose Blue Line station in Chicago on a cold and snowy morning Jan. 28, 2019. The inbound Kennedy Expressway is on the right.

The outbound Kennedy Expressway, left, and Edens Expressway, right, in Chicago on a cold and snowy morning Jan. 28, 2019.

Urszula Sieron shovels a path in front of her house in the 4400 block of West Montrose Avenue on a cold and snowy morning in Chicago on Jan. 28, 2019.

Don Milliken, of Palatine, clears snow from his neighbors’ sidewalks and driveways along Winston Drive in Hoffman Estates on Jan. 28, 2019. Milliken, a former Floridian, makes the most of the winter by pitching in and teaching scuba lessons at the Park District.

A woman waits for her bus following several inches of snowfall in Chicago, Jan. 28, 2019.

A man walks on West Irving Park Road in the Six Corners intersection in Chicago’s Portage Park neighborhood on a cold and snowy Monday morning, Jan. 28, 2019.

Commuters make their way in the snow in Berwyn on Jan. 28, 2019.

Traffic moves slowly through newly fallen snow on North Cicero Avenue in the Portage Park neighborhood of Chicago early on Jan. 28, 2019.

A pedestrian waits to cross North Cicero Avenue in the Six Corners area of the Portage Park neighborhood in Chicago as snow continues to fall early on Jan. 28, 2019.

Jim Brownlee clears snow that fell overnight in Flossmoor early on Jan. 28, 2019.

People trudge through newly fallen snow as they cross Michigan Avenue at Randolph Street in Chicago early on Jan. 28, 2019.

A pedestrian jogs along the lakefront near Monroe Harbor on Jan. 27, 2019, in Chicago.

Kathy Bakutis walks with her dog Chen on the Centennial Trail along the Des Plaines River as the temperature falls in Romeoville on Jan. 25, 2019.

Pedestrians walk through the snow near Buckingham Fountain in Chicago on a cold Jan. 27, 2019.

Alan Jimenez, 11, flies down an icy hill while sledding near Montrose Harbor in Chicago on Jan. 26, 2019.

Ice begins to form on Lake Michigan as cold weather envelops the city, as seen from the 360 Chicago observation deck in Chicago on Jan. 25, 2019.

Thousands of birds find a refuge on the Des Plaines River in Romeoville as the temperature falls on Jan. 25, 2019.

Bundled-up residents walk in Chicago’s Chinatown on Jan. 26, 2019, past red lanterns decorating the neighborhood for the approaching Lunar New Year.

Justin Leverenz reads the instructions for hand warmers before participating in the 18th annual Polar Plunge at Oak Street Beach in Chicago on Jan. 26, 2019. The air temperature was about 8 degrees during the event.

Participants run through Lake Michigan during the 18th annual Polar Plunge at Oak Street Beach in Chicago on Jan. 26, 2019. The air temperature was about 8 degrees during the event.

A man works at clearing snow in the Amtrak rail yard near Roosevelt Road during a cold weekend in Chicago, Jan 26, 2019.

George Arroyo, self-proclaimed mayor of a homeless encampment, stands by his tent along the Dan Ryan Expressway between Roosevelt Road and Taylor Street during a cold weekend in Chicago, Jan 26, 2019.

Blankets hang from trees blocking the wind at a homeless encampment located along the Dan Ryan Expressway between Roosevelt Road and Taylor Street during a cold weekend in Chicago, Jan 26, 2019.

Ice forms on Lake Michigan as cold weather envelops the city, as seen from 360 Chicago Observation Deck in Chicago, Jan. 25, 2019.

Ice begins to form on Lake Michigan as cold weather envelops the city, as seen from 360 Chicago Observation Deck in Chicago on Jan. 25, 2019.

Clad in blankets to keep them warm, Fintan, left, and Chester, right, stand in the sun at the Hoofed Animal Rescue & Protection Society (HARPS) on Jan. 25, 2019, in Barrington.

Cowboy nudges the coffee cup of Donna Ewing at the Hoofed Animal Rescue & Protection Society on Jan. 25, 2019, in Barrington. Cowboy wears a blanket so he can endure the frigid temperatures.

A man covers his ears as he walks on West Wacker Drive in Chicago on a cold and frigid morning on Jan. 25. 2019.

A man holds a dog as they enter a building at North Clinton Street at West Kinzie Street in Chicago on a frigid morning, Jan. 25. 2019.

Diversey Harbor on a cold and frigid Friday morning in Chicago, Jan. 25. 2019.

Pedestrians walk on West Wacker Drive in Chicago on a cold and frigid morning on Jan. 25. 2019.

Ice forms on a railing at North Avenue Beach as the sun rises over Lake Michigan and downtown Chicago with temperatures below zero and highs only reaching the single digits, Jan. 25, 2019.

Pedestrians walk on West Wacker Drive in Chicago on a cold and frigid morning, Jan. 25. 2019.

A man walks along the Chicago Riverwalk on a cold and morning, Jan. 25. 2019.

Canada Geese at Montrose beach in Chicago, Jan. 25, 2019.

Safe passage worker Margarita Panora keeps watch for children as she stands outside a school near W. 23rd Street and S. Leavitt Ave., as the cold weather envelops the city, Jan. 25, 2019. Panora was layered up with four shirts and three pairs of pants.

Below zero temperatures doesn’t stop a woman from exercising along the lakefront at Diversey Harbor on Jan. 25, 2019.

Commuters wait in below zero temperatures for a CTA Red line train at the Belmont station, Jan. 25, 2019.  (Steven Rosenberg/Chicago Tribune)

Steam cascades from buildings as the deep cold temperatures envelop the city, Jan. 25, 2019.

Miriam Hurtarte walks 3-year-old Sophie past a sign for Jonathan Burr Elementary School in the Wicker Park neighborhood on Jan. 24, 2019, in Chicago.

CTA passengers stand in a heat shelter at the Blue Line Damen stop on Jan. 24, 2019, in Chicago.

Bundled-up pedestrians make their way downtown as the polar vortex sends arctic air to Chicago on Jan. 24, 2019.

Bundled-up pedestrians walk past a mural on Cermak Road in Chicago on Jan. 24, 2019.

Bundled-up pedestrians make their way downtown as the polar vortex sends arctic air to Chicago on Jan. 24, 2019.