Cold weather has come knocking at our door

The UK is bracing itself for the first cold snap of the season Photo: Rui Vieira/PA Wire

After a cloudy and mild start the weather will do a 180 degree change by the end of the week.

Be prepared for the first cold snap of the season.

Why is this happening when it’s been so mild?

Cold air has never been far away, it’s been lurking to the north of Scotland for a while now.

To our southeast the near continent have had some warm weather recently as is typical for the time of year.

We have a band of cloud across the UK and this is the dividing line between the two air masses.

So our weather is on a knife edge. Over the last few days our winds have been southeasterly bringing in milder (and cloudier) air from Europe.

Later on this week the wind will flip to a northerly bringing in the cold air that is waiting in the wings and whoosh bring on the artic plunge.

Fog lingers in the air as a punt makes it's way along the River Cam in Cambridge Credit: Chris Radburn/PA Wire

When will it change?

Thursday night into Friday will bring the dramatic change.

Later on Thursday the winds will flip to a northerly, then a cold front will track south across the country allowing the colder air to rush in behind.

It will move through England and Wales during the early hours of Friday and through the Channel Islands around Friday lunchtime, by which time we will all be in this colder air.

If you follow the pressure lines you’ll see that they originate from the Artic, which will bring us this cold blast. For some we could have a drop in temperature of 8C in just 24 hours.

The Arctic cold blast is expected on Friday Credit: Met Office

What is the forecast for us and will it snow?

For the next few days the weather will repeat itself, right through to Thursday the weather will stay cloudy and murky.

There will be low cloud giving extensive hill fog.

Mist and fog will develop inland and again be reluctant to clear through the day, this could again lead to travel disruption.

With easterly winds eastern areas will be prone to the thickest cloud and outbreaks of rain and drizzle.

Western areas (and perhaps southeast England) could see a few breaks and this will allow the temperatures to pick up a little, maybe to the high teens.

Temperatures will be typically 13-17C, above the seasonal average of 11-13C.

Rooks perch on a tree surrounded by fog in Toft South Cambridgeshire Credit: Chris Radburn/PA Wire

Then there is high confidence for much colder air to spread across the country by Friday.

This will push away all the cloudy claggy weather with crisp sunshine making a welcome return.

During Friday we will see some wintry showers they will be confined to Northern Scotland and northeast England driven in on a cold northerly wind, which will gust to 20-30mph, giving a real wind chill.

Wintry means a mixture of rain, sleet, snow and hail.

Through the weekend the risk of wintry showers increases for these northern areas.

Snow will not settle to low levels by day, so don’t get those sledges out just yet, however we could see a covering across the hills in the north.

The cold weather will last into the weekend, temperatures will struggle to rise to double digits, at best they’ll be between 6-9C by day and will plummet below freezing at night, this gives the risk of icy stretches where any showers have fallen.

With the fog over the coming days and cold, potentially icy weather, keep checking the latest Met Office warnings: http://www.metoffice.gov.uk/weather/uk/ukforecastwarnings.html

The Met Office and the Government have put together some practical steps to get ready for winter: http://www.metoffice.gov.uk/learning/get-ready-for-winter