Dangerously cold temperatures across the US have been blamed for at least nine deaths. The plunge in temperature has wreaked havoc in some places, freezing a water tower in Iowa, halting ferry service in New York and leading officials to open warming centers even in the deep south.

Trump's call for some 'good old global warming' ridiculed by climate experts Read more

The National Weather Service (NWS) issued wind chill advisories and freeze warnings on Tuesday covering a vast area from south Texas to Canada and from Montana through New England.

Indianapolis tied a record low of -12F (-24C) for 2 January, set in 1887, leading Indianapolis Public Schools to cancel classes. The north-west Indiana city of Lafayette got down to -19F (-28C), shattering the previous record of -5F (-21C) for the date, set in 1979, the NWS said. After residents there began complaining of an audible hum, Duke Energy said it was caused by extra power surging through utility lines to meet electricity demands.

“The temperatures are certainly extreme but we’ve seen colder,” said Joseph Nield, a meteorologist in Indianapolis, noting that the all-time low temperature in Indiana was -36F (-38C) in 1994.

Nevertheless, the cold is nothing to trifle with, forecasters warned. With Chicago-area wind chills expected between -35F and -20F (-37C and -29C), forecasters warned of frost bite and hypothermia risks and urged residents to take precautions, including dressing in layers, wearing a hat and gloves, covering exposed skin and bringing pets indoors.

Facebook Twitter Pinterest A town recreational employee clears snow from an outdoor skating rink in Burlington, Massachusetts, on Tuesday. Photograph: Cj Gunther/EPA

Atlanta hospitals were seeing a surge in emergency room visits for hypothermia and other ailments as temperatures plunged well below freezing. The temperature in Atlanta fell to 13F (-11C) before dawn on Tuesday.

“We have a group of patients who are coming in off the street who are looking to escape the cold – we have dozens and dozens of those every day,” said Dr Brooks Moore, associate medical director in the emergency department of Grady Health System, which operates Georgia’s largest hospital in Atlanta.

The cold has been blamed in at least nine deaths in the past week.

Police in St Louis said a homeless man was found dead inside a trash bin on Monday evening, apparently frozen to death as the temperature dropped to -6F (-21C). Sheriff’s officials in Fond du Lac County, Wisconsin, said a 27-year-old woman whose body was found on Monday evening on the shore of Lake Winnebago probably died of exposure.

The Milwaukee County medical examiner’s office said two men whose bodies were found on Sunday showed signs of hypothermia. Police believe the cold weather also may have been a factor in the death of a man in Bismarck, North Dakota, whose body was found near a river.

Warming shelters were opened across the south as freeze watches and warnings blanketed the region, including hard freeze warnings for much of Louisiana, Mississippi and Alabama. Temperatures fell to 8F (-13C) near Cullman, Alabama, and 20F (-7C) in Mobile, Alabama. Georgia saw one of its coldest temperatures of the winter: 2F (-17C) shortly before dawn at a US Forest Service weather station at Toccoa.

Plunging overnight temperatures in Texas brought rare snow flurries as far south as Austin, and accidents racked up on icy roads across the state. In the central Texas city of Abilene, the local police chief said more than three dozen vehicle crashes were reported in 24 hours.

Facebook Twitter Pinterest Participants rush in the water during a polar bear plunge at the beach in Coney Island in New York. Photograph: Anadolu Agency/Getty Images

In Savannah, Georgia – where the January’s average high is 60F (16C) – the temperature hovered at 30F (-1C) at noon on Tuesday, cold enough for icicles to dangle from the ornate wrought-iron fountain in Forsyth Park at the edge of the city’s downtown historic district. The city could see up to 2in of snow and sleet on Wednesday, its first measureable snow since February 2010.

“I’ve never seen icicles in Savannah, period,” said Sean Dempsey, a local restaurant manager who wore a hat, gloves and a thick coat to walk his dogs. “I’m pretty sure last year at New Year’s lots of families were in the park playing catch, Frisbee football and stuff like that.”