27/01/2017 Weather for the Week Ahead

Hello. If you were watching Weather For The Week Ahead yesterday,

I was explaining about our blocked weather pattern,

the high pressure that's been sat across Europe

for the past week or two,

with its dense cold air,

and how reluctant it is to move away

to allow the normal succession of low pressures

to move in off the Atlantic.

It looks now as if things are going to change.

But again on Thursday

we've had the same sort of weather,

a real contrast where you've had the cloud

and where you haven't.

-2 under that continental cloud in the south,

12-13 degrees in north-west Scotland with the sunshine.

This is how it looked in Norfolk, with that grey cloud.

It was bitterly cold too

because there was a significant wind-chill as well.

But this the view at St Andrews in Scotland

and many parts of Scotland,

Wales, enjoyed the sunshine,

some late in the south too.

But through the night, as the cloud breaks

it's turned cold

and a frost is quite widespread

and that's the likelihood

as we head into Friday morning.

These are towns and cities.

In the countryside, it'll be colder still.

If you add on the strength of the wind,

it really will be raw out and about.

Not just that, we've the potential for

either a bit of rain

falling on frozen surfaces first thing,

or indeed potentially some snow for a time.

Then, as the day progresses,

we pick up more cloud heading northwards.

Low cloud and fog

first thing in the morning.

So it's cold in the east,

progressively less cold further west.

The start of a change.

The change is being brought about very slowly,

but during Thursday

we have the cold continental air.

Through Friday we have slightly less cold air

coming from the Bay of Biscay.

Finally, by Saturday, we start to pull in

Atlantic south-westerlies.

But it will still be cold in eastern areas

and very icy potentially in the west, Saturday morning.

and very icy potentially in the west, Saturday morning.

So we've still got a hint of winter.

The showers could still fall as snow over the hills.

But it's gradually warming up.

This is the fly in the ointment for the weekend,

this mass of rain behind me.

And exactly where it's going to go

is giving us a headache at the moment.

At the moment, it looks like

it'll affect southern parts of the UK.

To the north of that,

a cold, frosty start, but sunshine to be found.

That then whisks out of the way

Sunday night into the start of Monday

when we start to see the low pressures

getting progressively further northwards

and filling much of the North Atlantic,

as you can see.

So it's getting wetter,

with bands of cloud bringing that rain in

and windier too.

And by the time we get to Monday,

our temperatures are into double figures

in most parts of England and Wales,

and not for off for Scotland and N Ireland.

That area of low pressure dominates

most of the North Atlantic.

And fairly tightly packed isobars means

there will be gales

or even severe gale force winds at times,

as the more mobile weather situation takes over.

So, for most of the start of January,

we've had this blocking system.

The weather systems haven't been allowed

to run from west to east,

But the upper winds, the jet stream,

are now starting to strengthen

to allow more mobility,

more weather systems to cross the UK.

Next week, the high pressure's

still with us over continental Europe,

but the low pressures are being allowed

to make inroads into the north and west.

That's where we'll see the wettest and windiest weather,

but it looks like the whole UK

will be in a milder, slightly more unsettled regime.

This is a much lower probability

that potentially at the end of the week

those low pressures could head southwards

and pull cold air into the south and east again.

At the moment, though,

the majority of the computer models think

we'll keep with that south-westerly,

mobile weather picture.