The winter storm has prompted travel warnings on the Great Lakes.

The US National Weather Service (NWS) has put in place warnings of heavy freezing spray in the Great Lakes area until Sunday.

The NWS explains that this spray can make mechanical and electronic components "inoperative" and that ice buildup can lead to a "catastrophic loss of stability".

Dangers are also posed by strong winds. Gale force gusts are already occurring across Lake Michigan, the NWS says. In upper Michigan more widely, "the blizzard conditions will be about as strong as can be experienced".

In a separate update earlier in the week, officials said, external waves on Lake Superior could reach heights of 27 ft (8m) tomorrow.

Image source, Getty Images

In our last post, we referred to power cuts across much of the United States. Canada is seeing similar issues – like its neighbour, the easterly states are some of the worst impacted, according to a tracker on the website of Generac, external.

Quebec is so far the worst impacted, with almost 120,000 outages, followed by Ontario with more than 53,000. Out on Canada’s west coast, British Columbia is currently seeing about 5,000 outages.

No figures are currently showing for places such as Saskatchewan, Prince Edward Island and Newfoundland. We'll bring them to you as soon as they are available.

Hundreds of thousands of people across the US have been hit by blackouts, with some of the worst impacted states lying on America’s east coast, according to PowerOutage.US, external.

The worst hit state so far is Connecticut, which has more than 100,000 power outages, followed by Georgia with almost 90,000. Other areas with a high number of power outages include South Carolina, Texas and North Carolina.

On the west coast, Washington is currently the worst affected state, with more than 10,000 customers without power.

Other heavily impacted areas include:

Massachusetts – 58,000

New York – 47,000

New Hampshire – 35,000

Virginia – 30,000

Maine – 30,000

And these numbers appear to be rising all the time. So stay with us for updates throughout the day.

There have been warnings that the extreme cold weather could lead to frostbite on bare skin "within minutes" - so what is it and what is the danger?

• Frostbite is caused by a reduction of blood flow to the extremities - which is the body's natural response to cold

• Symptoms usually begin with the affected parts feeling cold and painful
• In extreme cases, the tissue can die and surgery - even amputation - could be necessary
• Someone with frostbite should be taken into the warm, and medical advice sought

In some parts of South Dakota, they do not have enough equipment to cope with the extreme weather.

Rosebud Sioux Tribe emergency manager Robert Oliver said workers were trying to clear roads which had about 10 feet (3m) of snow in some sections.

In one instance, a rescue of people stranded in their homes had to be stopped, he said, as the hydraulic fluid in heavy equipment froze.

Image source, Getty Images

Much of the US is covered by weather warnings and advisories, as you can see from the below tweet from the US National Weather Service.

Their latest map says blizzard and winter storm conditions are expected in the north, winter weather in the northwest, a hard freeze in the south, and wind chill in many other areas.

Officials are updating the map and providing more detail on this site, external.

More than 100 daily cold temperature records could be broken or matched in the next few days, the US National Weather Service has said.

• In Colorado, temperatures dipped to a record-breaking low of -9F (-23C) from 42F on Thursday
• The city of Cheyenne, Wyoming, set a record for its greatest one-hour temperature drop, after going from 43F to 3F within 30 minutes. Elsewhere in the western state, temperatures have dropped as low as -35F (-37C)
• Nearly a dozen record low temperatures were also set in neighbouring Montana

Image source, Government of Canada

Weather warnings are in place across much of Canada's most populous areas.

The above map - which is being updated on the website of the country's weather service, external - alerts the public to conditions such as extreme cold and snowfall.

The warnings are in place from the province of British Columbia in the west to Newfoundland and Labrador in the east.

Here's a quick look at what's been happening there:

• Airports from Vancouver to Toronto have warned of disruption and cancelled flights
• The warmer west coast has received more snow in less than three days than it would expect in an entire year, CTV reports
• Extreme cold warnings are in place in Alberta - meaning the temperature could reach -40C (-40F)
• A "weather bomb" system is expected to dump as much as 15cm (6in) of snow on the capital Ottawa - as well as Montreal
• Strong winds of 110 km/h (68 miles per hour) are forecast on the Atlantic coast

There are severe weather alerts reaching from coast to coast - and the storm is already sweeing large swathes of territory.

The pictures below show the conditions across the US.

• See more snaps here

Image source, Stephen Chung / Alamy Stock Photo

Image source, Stephen Chung / Alamy Stock Photo

Image source, Star Tribune via Getty Images

Image source, Jason Connolly/AFP

Image source, Seth Herald/AFP

The governors of New York state, Kentucky, North Carolina, West Virginia, Georgia and Oklahoma have declared states of emergency in anticipation of the storm.

Wisconsin has also declared an "energy emergency".

Kathy Hochul, New York state governor, said flooding and ice jams - when large pieces of ice block the flow of a river and cause flooding - are going to "wreak a lot of havoc in our community".

She asked residents to take care and avoid any non-essential travel.

The US government forecasting agency has described the extreme cold weather as a "once-in-a-generation" event, with among the most weather warnings ever issued.

The low temperatures are caused by an "immense winter storm" from the Arctic, the National Weather Service says.

This powerful front has caused temperatures to plummet by 30 to 50 degrees Fahrenheit in a short time, in many areas of the country.

And a low pressure system along the Arctic front in the Midwest/Great Lakes region will result in heavy snow.

Several places could see the lowest temperatures on record, as well as dangerous levels of wind chill, the NWS says.

In addition to flight cancellations and road closures, historic cold across the country has left states scrambling to create shelters for the homeless.

The cold weather will bring significant danger, experts have warned.

The low temperatures could lead to frostbite on bare skin in just five to ten minutes, the National Weather Service said.

"This is not like a snow day, when you were a kid, this is serious stuff," President Joe Biden said on Thursday.

The storm is already causing havoc on roads – in Wyoming, the Highway Patrol recorded 104 crashes and 787 calls for help in just 12 hours.

Image source, Getty Images

Welcome to our coverage as winter weather causes havoc across the US and Canada.

More than 135 million people from coast to coast are affected by weather alerts, as a powerful Arctic winter storm is set to bring temperatures as low as -70F (-57C) in some areas.

Thousands of flights have been cancelled, ahead of the busiest travel days of the year.

The National Weather Service (NWS) has warned that frostbite will be a major danger.

Stay with us as we bring you the latest from the area.

Image source, Getty Images