Significant cold is spreading widely across North America this weekend, having already affected northern and western parts so far this week.
During the night of 9 November, temperatures across central and western provinces of Canada, as well as many western states of the US, plummeted to at least 10C (18F) below normal, with some parts of Canada seeing temperatures as low as 20C (36F) below normal.
Temperatures fell below zero across a large swathe of North America, from northern parts of Arizona and New Mexico up to much of Canada. Minimum temperatures of as low as -25C (-13F) to -30C (-22F) were recorded across many parts of western Canada.
This weekend the cold will become extremely widespread and expand southwards and eastwards into eastern parts of the US as cold air plunges southwards on the west side of a north-eastward-moving area of low pressure. One location that is likely to see dramatic temperature changes as the frigid conditions continue into next week is Austin, Texas.
On Thursday, the city in southern Texas saw maximum temperatures into the high 20s celsius, but on Saturday will see maximum temperatures struggle to reach into the mid-teens.
Further to the north-east, 1,600 miles (2,600km) away in Boston, temperatures reaching a maximum of about 20C (68F) on Friday will then struggle to reach double figures by Sunday as the cold air moves in.
Throughout next week, the widespread cold will persist and by the end of the week most areas away from the coast and far south of the US will have seen snowfall.
Across the Atlantic in Lisbon, Portugal earlier this week heavy rain brought flooding to the city as well as a damaging tornado. The downpours were caused by an active front that swept in from the Atlantic on 8 November.
A tornado was reported forming briefly during the afternoon, touching down in the parishes of Alvalade and Alcantara in the city. The strong winds caused numerous fallen trees and damage to vehicles. Another tornado was reported to the north of the city earlier in the day as the front approached.
• This article was amended on 12 November 2022 to correct errors in the conversion to Fahrenheit of temperature changes on the Celsius scale; also, Boston was said to be 16,000 miles from Austin, rather than 1,600 miles.