Winter will start to hit the UK this week thanks to a sizable area of high pressure over Iceland that will push Arctic air southward.
Tuesday will see the first indications of this wintry weather as the cold air moves in over the UK.
Daytime temperatures in northern Scotland are expected to be barely above freezing, and sleet and snow showers may occur throughout the day.
Over the course of Wednesday, the cold front will move further south, bringing temperatures well below average for the time of year.
high pressure drags cold Arctic air toward the UK
There could be widespread frost and even snow on Thursday and Friday as temperatures are predicted to be more than 5C below average in many locations, as per The Guardian.
The cold spell is anticipated to last through the weekend, but by the following week, a low-pressure system will move in, potentially bringing sleet and snow to large portions of the UK before temperatures gradually return to average.
Winter weather will also be present in most of western Europe. The first half of the week will see temperatures fall in Norway, Sweden, and Ireland, with some locations experiencing drops of up to 10C from the seasonal average.
This icy blast will have moved southwest into parts of France, Belgium, Luxembourg, and Germany by the end of the week.
Central South America, on the other hand, is preparing for a heatwave that will hit northern Argentina, Paraguay, and south-eastern Bolivia.
On Tuesday, high temperatures are predicted to arrive, rising to 10C above the seasonal average.
This anomaly will become more widespread by Wednesday afternoon, with some locations experiencing Thursday highs of 47C, which is 15C above average for the time of year.
On Saturday, the heat wave will start to break, but temperatures will still be extremely high.
Read More: UK Weather Brought Back Another Summer Blast After Temperature Drop for the Past Few Days
A yellow weather warning for snow is also in place
According to Simon King of BBC Weather, a northerly wind from the Arctic will cause temperatures to drop significantly starting on Tuesday night and continuing through the rest of the week, with highs across the country ranging from 1C to 4C, several degrees below the average range of 6C to 9C.
Along with widespread hard overnight frost, Mr. King predicted that by the end of the week, temperatures would drop to between -2 and -6 degrees Celsius, as per BBC.
Despite the fact that only north-eastern Scotland is expected to experience snow, "the situation is that it will be cold enough for anywhere in the UK to see snow"
Due to above-average temperatures in October and a large portion of November and rising energy costs, many people postponed turning on the heating to warm their homes.
However, this might be harmful to those who are more susceptible.
According to the World Health Organization, a "warm home" should have a living room temperature of 21 degrees Celsius and a bedroom temperature of 18 degrees Celsius.
However, studies have shown that if people cannot afford to heat their homes, they will typically live in environments with an average temperature of only 10 degrees Celsius.
Speaking on behalf of Age UK, Sophie Barrett urged people to turn on the heat and make sure it is set at a temperature that will keep them warm inside their homes.
"We are hearing a lot of very sad stories, ranging from different extremes - some are sacrificing food for heating, others are saying they will be staying in bed all day to avoid getting cold," she said.
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