BRITAIN is forecast to be colder than Russia this week.
Lows of -7C (19F) were predicted for northern areas overnight.
The lowest temperature in Murmansk — Russia’s most northern city — were set to be just -1C (30F).
The forecasts were for widespread harsh frosts this morning with below average daytime temperatures.
The Met Office predicts highs of 13C (55F) in the south by Wednesday before the freeze returns next week.
The cold snap is expected to last at least three weeks, with frost and snow moving south. Cumbria has already had a sprinkling. The Weather Outlook forecaster Brian Gaze said: “It looks like an early winter.”
Ladbrokes slashed the odds of snow on Christmas Day from 5-6 to 4-5.
The plunging temperatures mean Britain will be much colder than Iceland, where the mercury would hover around 1C on Sunday.
A Met Office forecaster said: "The cold winds coming straight from the Arctic will carry with them a few showers and will be cold enough to fall as sleet or snow over some northern hills."
Icy blasts surged in from the west on Friday night, creating damp conditions and chilled the nation this weekend.
But the mercury dropped dramatically on Sunday night across the north and in the Scottish Highlands, with temperatures falling as low as -7C.
Harsh polar winds swept in on Sunday bringing snow across Scotland as the country remains gripped by the cold snap.
The conditions will only begin to improve by the end of the weekend but drier weather will make for frosts come this morning.
And the cold spell is forecast to last for the next few weeks as a Met Office spokesman said: "From November 26 to December 10, temperatures look like being below normal generally, with an increased risk of snow at times, especially in the North, and an increased chance of frost through the period.
“Minimum temperatures could exceed the coldest temperatures of the season.”
Met Office forecaster Emma Sharples added: “This would make it the coldest night (Sunday night) of autumn so far and the cold weather will last until mid-week before temperatures start to recover.
“We expect snow over high ground in the north on Sunday night and there could be wintry showers to lower levels."
She added: “Long-range prediction systems indicate this cooling is very likely to continue in the coming weeks, leading to a full La Nina event over the next few months."
Dangerous false widow spiders in search of warmth are also set to invade UK households amid the cold snap.
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