• Water tower freezes in Iowa and New York ferry service halted
• Indianapolis schools closed and snow flurries seen in Texas

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.

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.

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.