In severe cold, below -15C, before you turn the ignition key flash your main beams - this takes a bit of battery power and thaws it a bit inside.

BBC: Your tips for coping in a colder UK climate

After the severe weather, a cold-weather system could bring snow and freezing rain to the Midwest, beginning Wednesday, and the threat of extremely cold weather in the northern Plains states and Upper Midwest, particularly on Thursday.

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Symptoms and duration of cold were also much less severe - by about a third each - the researchers said.

BBC: Adults have two colds on average each year

Wales and south-east England are also expected to see some snow during Monday, with the far south-west of England and Northern Ireland being the only regions untouched by the severe cold.

BBC: Light snowfall in parts of Wales, and more expected

In North America, Laki has been blamed for the starvation of Inuit populations from severe cold in northwestern Alaska, based on Inuit oral history as well as tree-ring density data investigated by Gordon Jacoby and others, who estimated that conditions were about 4 degrees Celsius colder than the mean.

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