26/11/2015 Weather for the Week Ahead

Hello there. Fairly quiet through the day on Thursday,

but as we get on into the end of the week, into the weekend

and beyond, things are set to turn much more unsettled.

We do have some rain

through the day on Thursday,

across Northern Ireland through the morning,

getting up into the western side of Scotland,

we need to watch the rainfall totals because

there will be some heavy downpours.

The western side of England

and Wales pretty grey,

some outbreaks of light rain and drizzle.

But the rain in the western side

of Scotland could be heavy for a time,

the eastern side drier,

but a little rain certainly likely.

Rain crosses Northern Ireland

then it's fairly cloudy into the afternoon,

maybe further spells of rain,

and the rain is lurking there

in the Irish Sea for the afternoon,

but ahead of that a lot of cloud,

some of that quite low,

but there should still be spells

of sunshine across East Anglia

and the south-east into the afternoon.

You'll get nine, ten degrees,

11 or 12 in the south and west,

but a lot of cloud, some of that quite low,

a little light rain and drizzle to go with that.

Some damp weather drifting

across England and Wales

through the overnight period,

as the winds pick up from the south and west,

which will keep things mild for most of us

to start the day on Friday, but -

there is an active weather front

drifting towards the north and west.

Let's take a look at the big picture for Friday,

because developments are taking place.

Weather fronts heading our way,

lots of isobars on the chart,

so it is going to be a blustery day on Friday,

but the winds across England and Wales

coming in from the south and west,

so it's mild but cloudy, outbreaks of

rain and drizzle through the morning.

This is the squally cold fronts

which will bring heavy rain and gusty winds

to Scotland and Northern Ireland.

That then drifts its way

across England and Wales,

probably getting towards

the south-east through the evening,

but mild in spite of all the wind

and rain, 11, 12, 13 degrees,

but behind that rain

it turns cold quite quickly.

Friday night into Saturday there will be snow showers

across the hills of northern Britain,

maybe getting down to

lower levels of northern Scotland,

before the next system arrives

for the start of the weekend.

Yes, a spell of wind and rain.

Some rain will be heavy,

the winds could be gusting to gale-force around

the coast and hills in the south and the west,

and it's going to feel

pretty chilly underneath all of that.

Particularly in the wind,

which continues to blow through

the second part of the weekend,

a brief respite before the next weather system

comes in to the north in particular on Sunday.

Another spell of wind and rain,

need to watch those rainfall totals

again in the west of Scotland,

cos they will be totting up.

Single figures in the north of the UK,

that bit drier further south,

and temperatures should be into double figures.

Does it get any better into the start of the new week?

Not for the northern half of the UK.

The next system is on its way.

Again, a lot of isobars in the chart

so it will be windy, it's going to be wet again

in the western side of Scotland, northern England.

South of that, it's cloudy and breezy

but relatively mild,

but again, with that rain

it's going to feel quite chilly.

So some very lively weather

over the next few days,

and it's going to last well

on into next week, because we've got

this very powerful jet stream

developing across the north Atlantic.

Core winds will be

170mph to 200mph or more,

and that's going to drive a series

of weather systems across the Atlantic.

Why is the jet stream so powerful?

It's because we've got

a very sharp temperature gradient

out in the mid-Atlantic,

you can see the change in the temperature

of that air at altitude

across quite a short distance,

hence a lot of energy being exchanged and a strong jet stream.

The pressure pattern into

early December sees high pressure

in the south,

low pressure in the north,

westerly winds bringing some rain

to the north and west of the UK.

Signs are that the jet might

move north into early December

allowing the high to move

into the south, settling things down,

but still in the north and west

it looks pretty wet and pretty windy.

We do BBC School Report every year.