10 day trend – how hot will it get and how long will it last? 29/05/19 - video Dailymotion

Met Office

Whilst the mercury is set to rise this week, it won’t be sunny everywhere and it probably won’t last all that long. Alex Deakin looks at the reasons for the rising temperatures and the uncertainty in whether we see thunderstorms as it turns cooler.

Transcript

00:00Welcome to the 10-day trend that takes us into summer.

00:04Yes, meteorologically and climatologically,

00:06summer starts on the 1st of June on Saturday.

00:09And this year, it could well coincide

00:11with some summer-like weather.

00:13We are expecting temperatures to rise.

00:16And for many of us, we'll see some sunshine on Saturday.

00:19Now, it is going to be warming up pretty much

00:21across all parts for the rest of this week.

00:24It will be turning sunnier for many,

00:26but not everywhere is going to see blue skies,

00:30and particularly in parts of the north and the west,

00:32there will be further outbreaks of rain

00:34over the next couple of days.

00:35And then the big question,

00:37how long is the warmer weather going to last?

00:39And the short answer is not very,

00:42because for next week, we're back to low pressure.

00:45We're back to much cooler conditions,

00:47and we're back to plenty of showers.

00:49The really interesting question meteorologically

00:51is how are we going to change from one to the other?

00:55And what's the weather going to be like

00:56as we see that transition during the weekend?

01:00More on that in a moment.

01:01Let's get into the detail of how warm

01:03we're going to see things over the next few days,

01:06because this is the setup,

01:07big area of low pressure out in the Atlantic.

01:09And it's in here where things are warming up.

01:11This is called a warm sector, quite a broad warm sector.

01:15And it's in here behind this warm front,

01:17the warmer air is pushing its way up across the country.

01:21But notice there are weather fronts just dancing

01:23and dribbling their way across parts of northern Britain.

01:27And they will always bring cloud and some outbreaks of rain.

01:29So as I said at the start,

01:31it's not turning hot and sunny everywhere.

01:33On Friday, the warmth really confined

01:35to central and eastern parts of England.

01:37And let's run through Thursday and Friday really quickly,

01:40because this shows you the contrasts,

01:42bands of cloud and rain coming into Scotland

01:45and Northern Ireland,

01:46whereas for much of England and Wales,

01:47it's dry and a big temperature contrast on Friday.

01:50If we see some sunshine across the southeast,

01:53easily into the low 20s,

01:54whereas it stays cool across the northwest,

01:58only 12 or 13 here with some outbreaks of rain.

02:01Now, Saturday is the day where we'll see

02:03the most widespread heat, if you like.

02:06But again, it is mostly across England and Wales,

02:09still across Scotland and Northern Ireland.

02:11Temperatures, yes, are rising,

02:13but nothing spectacular here,

02:15maybe 18, 19 in the northeast of Scotland.

02:18But for the bulk of England and Wales,

02:20Saturday, widespread warmer weather.

02:23We could get up to 28 or 29 across parts of the southeast.

02:28The coasts will be cooler

02:29and the coasts may stay a bit misty and murky.

02:32But inland, we're looking at 24, 25 degrees Celsius.

02:35So we're likely to see the warmest day of the year so far,

02:39probably on Friday and maybe again on Saturday.

02:43Big question is, as I said,

02:44how long is that going to last?

02:45And well, Sunday may well be the day

02:47when we start to see a change.

02:50This graphic here shows how widespread

02:52the warmth is likely to be.

02:54This is Saturday's chart.

02:55This isn't the temperatures.

02:56This is the temperatures compared to average.

02:59And you can see there, red colours

03:00for most of England and Wales.

03:02We are well above average here,

03:04not so much for Scotland and Northern Ireland.

03:06Compare that to Friday,

03:08we're just a few places a little bit above average on Friday.

03:11That's the day we'll start to see the warmth

03:13depending on the sunshine.

03:14Widespread warmth across England and Wales on Saturday.

03:18How long does it last?

03:19Well, it looks as if things are turning cooler on Sunday,

03:22but there's a lot of uncertainty

03:24about the timing of things turning colder.

03:27But you can imagine from these graphs,

03:28actually we've got a cold front swinging across the country

03:31and that's what we are expecting.

03:33On Sunday, a cold front swings through

03:35and introduces cooler air.

03:37But there is much uncertainty about the position,

03:40the timing and indeed the intensity of this cold front.

03:44It could be bringing some thunderstorms

03:47as it moves across the country.

03:48So as I said, some uncertainty.

03:50Let's rewind the clock

03:52and show you why there's a bit of uncertainty

03:54and trace this area of low pressure going back in time

03:57all the way to the eastern seaboard of the United States.

04:02As I speak, it's forming out across the eastern seaboard

04:05and there's a lot of activity in the US at the moment.

04:07Again, another day with severe thunderstorms across the US

04:11and potential tornadoes breaking out.

04:14And that kind of severe weather can then impact

04:18on things high up in the atmosphere.

04:20This is the jet stream coming out of the United States.

04:24And as I say, things really could develop

04:26over the next couple of days

04:27with that area of low pressure,

04:29depending on the intensity,

04:30depending on the number of thunderstorms we see in the US,

04:33how that then interacts with the jet stream.

04:35You can almost see the jet almost kind of splitting there

04:38with two arms to it.

04:39So it gets very complicated through Thursday

04:42and then the next few days, the jet tends to drive.

04:45And it's this little trough

04:47which then develops the low pressure,

04:48which becomes the cold front

04:50that swings across the country on Sunday.

04:52It's pretty complicated.

04:54And that's why I'm showing you this

04:56just to show there's a lot going to happen

04:58in the next few days, high up in the atmosphere,

05:01thousands of miles away across the Atlantic

05:03that will determine the position of this cold front

05:06on Sunday.

05:08What does that mean?

05:09Well, it means that Sunday is the day

05:10we're likely to see the change.

05:12We are likely to see some thunderstorms

05:14triggered by the heat and humidity,

05:16but there's big question marks

05:18about exactly where and when.

05:19So stay tuned for updates

05:21because Sunday could be a very lively day.

05:23It may be one more hot day across the East,

05:26just depends on the timing

05:28of that cold front swinging through.

05:31Beyond Sunday, well, actually the weather

05:33becomes a little bit more straightforward.

05:35It's one of those slightly counterintuitive scenarios

05:37where there's a lot of uncertainty about Sunday,

05:40but beyond Sunday, we're reasonably confident

05:42in the forecast because the jet stream

05:44becomes not standard,

05:46but back to a more typical scenario

05:49coming out of the Atlantic

05:51and taking low pressure systems

05:53just to the north.

05:54So the most likely scenario

05:55for the early part of next week

05:56is that low pressure will dominate

05:58to the northwest.

05:59And of course, with the jet slipping back

06:00further south, we will chiefly be

06:03on the cold side of the jet.

06:05So for the first half of next week,

06:07certainly it looks as if it will be

06:09on the cool side and we'll see showers

06:11or longer spells of rain.

06:13And this graph shows that quite nicely.

06:15Two graphs here.

06:16The one on the top is for Reading

06:18and the one further down

06:20to the bottom there is Edinburgh.

06:22Now, I just really want you to focus

06:23on the red blobs.

06:25That's the most likely maximum temperatures

06:27as we go through the next few days

06:29and into next week.

06:30The dates there along the bottom,

06:31this red line is the average temperature

06:34for the time of year and the red nodules

06:36suggesting the temperature spread

06:38for the next few days.

06:40So we can see here for Reading,

06:41the temperatures are expected to rise,

06:43probably peaking on Sunday

06:45before we see a drop in temperatures.

06:46And for much of next week,

06:47temperatures are expected to be below

06:50or at or below average.

06:51And the same goes for Edinburgh.

06:53You can see that trend here,

06:54the rising and the dropping

06:56of those temperatures.

06:56So the scenario is warmer weather,

06:59yes, for the next few days,

07:00peaking probably on Saturday

07:03and then turning cooler

07:04next week with showers.

07:06May turn a bit warmer, a bit drier

07:08towards the back end of next week.

07:10But I think you'll agree there's plenty

07:12to get through before we get there.

07:14The best thing for you to do is to stay

07:16tuned to the updates

07:18down at the Met Office app

07:20or follow us on social media

07:21to see just how hot you could get

07:23on Saturday and to see if there will

07:25be some big thunderstorms around

07:28on Sunday.

07:29Thanks for watching.

10 day trend – how hot will it get and how long will it last? 29/05/19

Category

Transcript

Recommended