26/01/2017 Weather for the Week Ahead

Good evening.

This time yesterday, John was explaining

how dry it's been in the last couple of months,

and that's because we've had high pressure close by.

A blocked weather pattern.

That means that the jet stream across the UK

is quite weak.

It's diving to the south,

that's where the strength is,

pushing the low pressures across Iberia

and into the Mediterranean,

whilst the high pressure across Europe

is blocking the passage of weather fronts,

which bring out wind and bring our rain.

So, again, we go into Thursday

with this blocked weather situation.

We've got a southeasterly continental air flow,

which is bringing in colder air

than we had on Wednesday and hill fog,

as opposed to low level fog.

So still pretty grey

for most of us first thing, and cold.

Colder, I think, than Wednesday morning.

It'll stay quite grey for much of the day,

but temperatures out in the countryside first thing

will be pretty low, -3, -4.

Because the cloud is quite thick,

it's giving us already a little bit of drizzle,

a little bit of snow.

Snow graze, not a great deal to amount to,

but, nevertheless, giving us some quite icy conditions

on untreated roads and pavements.

Through the day, little changes.

Under that cloud, it really will feel cold.

The best chance of some sunshine

is to the north-west of Scotland,

and later in the south.

But temperatures where we've got the cloud

barely get above freezing.

You add on the wind,

which will be stronger on Thursday,

and it will feel much colder.

Now there's a subtle wind direction change on Friday

from instead of that southeasterly,

we get more of a southerly off the Bay of Biscay.

Still quite a strong wind,

but it means it will be marginally less cold.

Still cold enough, I think, initially

for a smattering of snow

through the first part of Friday in southern areas,

eastern areas too.

Primarily, we start to see some heavier showers

coming into the west as the day progresses.

So perhaps the start of a change -

our first weather front to come

knocking on the door of that high pressure again

and trying to move it out of the way.

Actually, it looks as if

it might succeed through Saturday.

We might get that band of showery rain,

or bands of showery rain,

moving through across the UK,

temperatures above freezing,

still cold enough for them to fall as snow,

those showers over the hills.

Then that low pressure moves away.

The next one dives southwards

across France and the low countries, we think.

At this stage, Sunday is looking

like the drier day of the weekend,

with some good spells of sunshine.

Not warm sunshine.

Again, we're only talking about

6-8 degrees Celsius,

but it is a more mobile situation.

We've had one weather front moving through

already on Saturday. So, yes, the weekend -

less cold, still quite a few showers around,

we think, on Saturday with more sunshine come Sunday.

Then, into Monday, it looks as if things start

to become more mobile.

You can see those low pressures starting to line up.

They do look a little bit more ferocious.

Not too nasty at this stage,

but they do look as if they've got

more energy in them, if you like,

to try and move this high pressure away from the UK.

So, eventually some rain comes through

during the course of Monday.

It's because -

well, you can see for yourself.

By the early part of next week,

we've got a much more west-to-east jet stream.

It's stronger across the UK.

It's more likely to bring us in some rainmakers -

some wind and some rain.

High pressure still close by,

but the chances are,

we think, that the low pressures

will also start to bring in

that change to wind and rain.

It's how quickly and indeed

how far south and east it comes

when it comes against

that blocking high pressure

that's been with us for,

well, a significant amount of time now.

So, yes, it does look as if we'll see some rain next week,

and it'll become windier. Gales, severe gales in the north and west.

It's just how quickly it moves across the whole of the UK

to affect the south and the east as well.