All change with our weather this weekend as winter bites back

Gritting Lorry at a Depot in Huntingdon, Cambridgeshire as Weather Forecasters predict snow across parts of the country at the weekend Photo: Chris Radburn/PA Wire

Temperatures are expected to drop everywhere over the weekend, with snow and wintry showers expected in Scotland and down the east coast.

ITV Daybreak's weather presenter Laura Tobin explains what is happening to the change in weather:

Why this sudden change to colder weather?

It's all down to wind direction.

So far this year it's been mild because our air has been coming from our west, originating in mild Atlantic waters.

This weekend, it will all change as an area of low pressure tracks through southern areas then moves away into France, this will cause a 180 degree flip in our winds to a northeasterly.

This will then drag much colder air from Scandinavia, spreading it right across the UK.

Not only will it turn colder with tumbling temperatures and widespread frosts returning but the thing we all want to know about is the snow, love it or hate it there will be some.

What’s the cause?

It’s all believed to be linked to a meteorological event called sudden stratospheric warming (SSW).Put simply it’s caused by sudden warming in the stratosphere, (the layer of atmosphere above the troposphere where our weather occurs), this causes the upper winds to change direction, from the usual easterly to a westerly, and in turn this can be linked to the winds near the UK, also changing direction, from our usual mild westerly to cold easterly.

What does this mean for you, will it snow this weekend?

Saturday:

There could be quite a bit of snow around.

After another chilly start with a touch of frost, a weather front will move into the southwest bringing cloud and rain to Wales, southwest and southern England.

As this bumps into the cold air, it’s a recipe for the rain to turn to sleet and snow.

At the moment the areas likely to be most impacted by the snow are southeast Wales and the south west Midlands, 5-10cm on the hills and 2-5cm to low levels.

As this eases and moves east during the afternoon other parts of the Midlands and maybe the Home Counties could also be affected.

Elsewhere largely cloudy and chilly with eastern Scotland and England starting to see sleet and snow showers developing giving at least a centimetre or two.

This weekend, it will all change as an area of low pressure tracks through southern areas Credit: ITV Daybreak

Sunday:

A frosty and, for some icy, start.

As the low clears from the east we start to drag in the freezing northeasterly winds.

This will bring scattered sleet and snow showers to Eastern England from Yorkshire south, hit and miss but sufficient to give some accumulations of snow in places.

Elsewhere chilly but fine, but not in the northwest, as a weather front will push in, bringing rain to Northern Ireland (maybe snow on the hills) but for Scotland the risk of more significant snow through the day, especially on the hills but a few centimetres to low levels.

This is one to watch as its progress keeps changing, so confidence is low.

Snow expected this weekend Credit: ITV Daybreak

How long will it last?

The cold spell of weather could last at least two maybe three weeks, especially in the east.

Many weather models are run around the world and some want it to turn milder again later next week, notably in the west, most however want to keep our weather cold and it will be.

Daytime 1-3 degrees celsius at best for some and at night will be as low at -10 degrees celsius.

Prolonged cold weather can cause a risk to your health.

There is a reasonably high confidence that cold is the most likely scenario and we will need to be prepared and keep watching national and local weather forecasts and check metoffice weather warnings.

The longer the easterly is with us, the greater the risk of significant snowfall developing, also sub zero temperatures will cause icy conditions.