24/10/2016 Weather for the Week Ahead

It's been a bit of an odd month so far,

not really following the normal pattern.

We've had an absence of westerly winds,

so areas that would normally be very wet at this time of the year,

such as Stornoway, have had significantly less rainfall.

It's been drier than average in Pershore as well.

Further east we have had some showers.

Some areas, such as Weybourne, have had more than average rainfall.

But the showers have been hit and miss

and they've been driven on by an easterly wind.

Now, we start the week ahead with an easterly breeze,

quite a chilly start as well.

But from midweek onwards things will turn milder,

less mist and fog and frost, because we'll get a westerly wind.

We start Monday, though,

with cloud across more southern parts of the UK with some outbreaks

of showery rain across south-west Wales, south-west England.

There's the threat of some torrential downpours

and thunderstorms too.

For northern England, Scotland and Northern Ireland,

after that chilly start with some patchy fog

there'll be some sunny spells.

Fewer showers, lighter winds in eastern Scotland -

the showers are really just bumping onto the coast.

As we head through the evening, though,

temperatures fall away quite sharply in the north

with the clearer skies, a frost developing.

Further south we hang onto enough cloud to keep the temperatures up,

but as well as the frost, particularly in Scotland,

we're going to find some patches of fog as well.

Now, eventually we'll start to see some changes

as these weather fronts encroach from the Atlantic.

But pressure's quite high and there's really

no wind to speak of for most of Tuesday.

That's why we've got the frosty and foggy start for many northern areas.

That fog may linger for most of the morning,

but then we'll get some sunshine coming through.

Further south the clouds should be thinner,

the downpours having cleared away from the south-west.

Most places will be dry.

15 degrees, perhaps, across southern parts of the UK,

11 or 12 in the north.

Wednesday we start to see a change in the wind direction -

a westerly arriving, much stronger across northern parts of the UK.

This weather front not bringing an awful lot of rain but

signalling a significant change with temperatures on the rise.

Why is that happening?

Look out to the other side of the Atlantic and off the eastern

side of Canada there's a plunge of colder air.

Ahead of that, closer to us, we've got warmer air aloft

moving northwards, and the clash strengthens the jet stream.

Really strong, the Atlantic jet stream

developing from midweek onwards.

The position of the jet means that to the south of it

high pressure builds in,

and that will dominate across more southern parts of the UK.

To the north on Thursday there will still be some strong

and really quite gusty winds and the chance of some rain

mainly over the hills in the west of Scotland.

For much of England and Wales it'll be dry and bright,

a little sunshine, the winds lighter and those

temperatures 13-16 degrees, so really quite mild.

We've got those weather fronts on the scene across the north

and north-west on Friday, higher pressure across England and Wales.

Some patchy rain mainly for the hills of western Scotland.

There will be more cloud for other western areas of the UK.

Best of the sunshine in the east

but above-average temperatures to end the week.

It's high pressure...

The position of high pressure that's really going to be crucial

over the week ahead.

The weekend sees high pressure building in across the UK,

pushing the rain away towards the north-west.

So again, it's dry, there may be some mist and fog

and maybe a touch of frost perhaps

where we've got those lighter winds and clear skies.

Somehow, the high pressure looks like it's going to move away.

There's differences in the computer models but there's

a signal for the start of November to get a northerly wind,

so much colder, perhaps some showers,

some sunshine and maybe a touch of frost.