People in the parts of the US are being warned to stay indoors as some of the coldest weather in a generation hits.
At least eight people have died as freezing temperatures hit the US.
The weather system – known as a Polar Vortex – has seen a blast of Arctic air sweeping through the upper Midwest of the country, with the wind chill making it feel like -46C.
Temperatures have plunged as low as -32C in North Dakota with wind chills as low as -52C in Minnesota.
Schools have been closed and flights cancelled due to severity of cold.
In Iowa, residents are being urged to protect their lungs by avoiding taking deep breaths and talking as little as possible when outside.
What can we say, strange things happen when it gets this cold 😆
Photo credit: Sarah Schneewind in Southern MN today. pic.twitter.com/OO0AsIJLsm— NWS Aberdeen (@NWSAberdeen) January 30, 2019
Leon Whitener is from St Louis City Fire Department in Missouri. He's working with other authorities to keep rough sleepers safe and warm.
“It is a tough situation for us to be in,” he said.
“We know that these temperatures are very dangerous and yet a lot of our homeless are comfortable where they are.
“They don’t understand the challenges sometimes with these really cold temperatures.”
Steam is seen rising off the frozen Lake Michigan in Chicago, 30-01-2019. Image: Xinhua/Patrick Gorski
A harbour light is covered by snow and ice on Lake Michigan at 39th Street Harbour, 30-01-2019. Image: Nam Y. Huh/AP/Press Association Images
Michigan Governor Gretchen Whitmer has urged all residents to “voluntarily reduce their gas usage” after an incident in the southeast of the state.
“I’m coming to you now to ask for your help,” she said in a statement.
“Due to extremely high demand for natural gas with these record low temperatures and a facility incident, Consumers Energy has asked that everyone who is able to turn down their thermostats through Friday at noon do so, so we can all get through this with minimal harm."
A cyclist decked out in cold weather gear rides past the city skyline in Minneapolis Minnesota, 30-01-2019. Image: Anthony Souffle/Zuma Press/PA Images
"You can play a role in helping people across the state survive these extreme temperatures.
“Please do. We’re calling on every Michigander to do your part and help us weather this storm together."
In Chicago, the cold is so intense that the train service has set the train lines on fire to keep them from freezing up so badly that trains cannot use them.
