Birmingham is warned that the city could be as cold as MINUS five this week.
Brummies preparing for the weekend will have temperatures of -5 ° C on Friday.
The coldest mercury levels are registered at 9am, according to a five-day forecast by the Met Office.
Monday is not as windy as on the weekend with different clouds and some bright or sunny periods.
Some slight showers may temporarily affect the region, but most are dry.
The sky is cloudy towards evening.
However, today's high of 9 ° C will far exceed the level of mercury expected this week.
Expect it to get cloudy overnight and occasionally light drizzle.
Most areas become a bit breezy, but it stays frost-free.
On Tuesday it should be mild and breezy, the sky is cloudy and can occasionally drizzle slightly.
However, some bright or sunny periods are possible.
Windy on Wednesday with lots of rain, followed by showers over night.
After that, it is colder overnight, but bright in the frost.
Maybe on Friday cloudy with some rain.
It is predicted that frost will prevail, with frost over night and the possibility of rain showers in some areas.
Meteorologist Bonnie Diamond said the cold polar air from the northwest would become a colder Arctic airflow from the north.
She said, "Wednesday will see a polar sea air mass penetrating from the west, but by Thursday we will be an Arctic air mass."
Northeastern Scotland saw snowfall on Monday and expected rain showers could turn to snow in the western United Kingdom on Friday, she added.
The average daily temperatures in southern England will barely rise above 6 ° C, she said.
While this is the average for January, Ms. Diamond said that after such a mild January, the contrast makes people grab their warmest coats and thermals.
She said: "Apart from the strange cold spells for some parts in the first half of January, it was relatively mild, but this week is a transition to colder weather for the entire country and will be felt by all of us and we are moving from that to colder temperatures really felt. "
The Met Office said there was evidence that cold air could reach the UK from the east to the end of the month and into February. However, it was warned that this does not automatically mean the return of the so-called Beast from the East brought heavy snowfall.
Ms. Diamond said, "Just because the wind is coming from the east does not necessarily mean that we will see a repeat of last year."
In parts of Europe, extreme weather prevailed at the beginning of the year, and Austria's forerunner experienced the highest snowfall in January since 1923, she said.