This is an in-depth Met Office UK Weather forecast for the next week and beyond. There are heavy thunderstorms for many at the moment, but the bigger talking point is the intense and persistent rain many will have on Wednesday. We try to clarify some of the details whilst there is still some uncertainty. Bringing you this deep dive is Met Office meteorologist Alex Burkill.
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00:00 There are some thunderstorms around at the moment and then tomorrow is going to bring
00:04 some heavy persistent rain for many of us.
00:06 It is going to be a pretty wet day.
00:09 Hello, welcome to your latest deep dive.
00:11 I'm Alex Burkle, presenter and meteorologist here at the Met Office and I'm coming to you
00:16 from our headquarters in Exeter.
00:18 And like I said, there is some pretty unsettled weather to come.
00:21 So let's dive in and have a look at what's going on.
00:24 Starting off though with what happened yesterday.
00:27 And if we look at the satellite and if I put the radar imagery on for yesterday and if
00:33 I zoom into the UK a bit, just so we can see a bit more detail, and we can see the heavy
00:38 thundery downpours that developed across parts of Western Northern Ireland and the Republic
00:44 of Ireland.
00:45 In fact, there were reports of a tornado spotted in Northern Ireland, though it may have actually
00:50 been over the Republic of Ireland.
00:52 There were also reports of a funnel cloud over Dartmoor in Devon too.
00:56 So a very unsettled picture for some of us.
00:59 Lots of the UK though had a fine, sunny and rather warm day too.
01:03 Now let's dart ahead to what's happened so far today.
01:06 And we've seen even more showers kicking off again across parts of Northern Ireland and
01:11 the Republic of Ireland.
01:12 Some heavy torrential downpours here.
01:14 We also have some showers kicking off across parts of Southwest England, some heavy, some
01:18 thundery ones.
01:20 And then we have this swathe of cloud with some embedded convection, some heavy, perhaps
01:24 even thundery rain pushing in across parts of the southeast.
01:28 So it is really an unsettled picture for quite a few parts.
01:31 But again, not everywhere.
01:32 Apart from a few showers across parts of Scotland, it's a largely dry picture there and also
01:37 for parts of Northern England and for Wales for now, although some showers could well
01:42 develop across parts of Wales.
01:44 In fact, one or two are starting to develop as we go through the rest of this afternoon.
01:48 Why have we seen so many thunderstorms?
01:50 Why is it so unstable at the moment?
01:53 Well, I mentioned there's some warmth across the UK and so generally temperatures have
01:57 been above average for the time of year.
01:59 And the sun at this time of year has some decent strength behind it as well.
02:03 So that really warms things up.
02:04 At the same time, we have some fresher, cooler air coming in aloft, so higher up.
02:10 And that leads to an unstable atmosphere.
02:12 So a bit of energy at the surface will then allow parcels of air to rapidly rise up.
02:18 And that leads to the big clouds, the cumulus, cumulonimbus clouds to develop.
02:25 And that leads to our thunderstorms, some large hail, some torrential downpours, could
02:29 even be some gusty winds mixed in with them too.
02:32 But there's more to come.
02:34 Not necessarily going to be the thunder that's the biggest cause for concern as we go into
02:37 tomorrow, but the heavy persistent rain.
02:40 If we look at the bigger picture and if we take a look at what's happening currently
02:44 over in Europe, and there's a system that's been developing over Central Europe for the
02:50 last day or so.
02:51 And that's brought some heavy, intense thundery downpours to parts of France, parts of Germany,
02:55 for example.
02:56 But it's heading its way northwestwards towards the UK.
02:59 And it's going to spill in as we go through Tuesday night into Wednesday, bringing some
03:04 heavy persistent rain to parts of the UK as we go through tomorrow and into Thursday as
03:10 well.
03:11 So this is the latest model data from the Met Office.
03:13 And you can see a big swathe of very wet weather pushing its way across many parts as we go
03:18 through tomorrow morning.
03:20 And then it continues and gradually makes its way north and westwards.
03:24 But because of the position of this low pressure system, some areas are really going to see
03:29 a lot of heavy persistent rain through a big chunk of Wednesday.
03:34 Then that low continues gradually to fill a little bit, but all the time is bringing
03:39 some further outbreaks of wet weather across many parts of the country as we go through
03:43 Thursday.
03:44 And it's not really until later Friday that it really starts to clear away.
03:48 By that point, it will have eased and broken up a little bit.
03:50 So the rain won't be as intense, but it is going to be a pretty wet picture as we go
03:55 through the rest of the week for many places.
03:57 The heaviest rain, though, likely to be as we go through Wednesday and early on Thursday.
04:02 But there is some uncertainty as to exactly where we're going to see the heaviest rain
04:06 and where is most likely to be impacted.
04:09 But if we take a look at some of the details of what we're suggesting at the moment in
04:13 terms of Wednesday into Thursday's rainfall, and this chart, we are going to be sharing
04:18 it on our social media, but I wanted to share it with you now as well, highlights some of
04:23 the areas where we're likely to see some heavy, possibly impactful rain.
04:28 Let's take a look at the most concerning area, perhaps this purple area over parts of North
04:33 Wales into northwest England.
04:35 In this area, 60 to 100 millimetres, possibly in excess of 150 millimetres as we go through
04:41 Wednesday and into Thursday.
04:43 The highest totals, 150 plus, most likely over the highest ground, Snowdonia, for example.
04:49 That's where we're most likely to see those very high rainfall totals.
04:52 But it could be in other areas that it's going to be very wet as well.
04:57 And you can see there are other coloured areas.
04:58 This blue section talks of the potential for 40 to 60 millimetres quite widely, 70 to 120
05:05 millimetres locally.
05:06 So in excess of 100 millimetres in a few places, that's quite possible as we go through Wednesday
05:12 into Thursday.
05:13 Now, the green area is much broader and shows that there's a potential for 50 to 60 millimetres
05:19 locally in this area, which is a lot of rain to come in just a day or so.
05:23 And it's a very broad area, covering partly for the fact that there is some uncertainty
05:29 as to where we're going to see the heaviest rain.
05:31 I'll come on to that in a second.
05:33 It's not just the persistent rain, though, that could cause some problems on Wednesday
05:37 into Thursday.
05:38 We also need to bear in mind that there could be some hefty showers around.
05:41 So this yellow area across Scotland talks of some slow moving showers.
05:45 And this orange area across southern parts of England talks of some further heavy thundery
05:49 downpours, which could bring 30 to 40 millimetres perhaps in just a few hours.
05:54 And with the thundery downpours, the other risks with frequent lightning and some large
05:59 hail perhaps too.
06:00 So some very hazardous weather to come as we go through Wednesday into Thursday.
06:04 There will also be some blustery winds around, but it's the rain really that's most likely
06:08 to cause some impacts.
06:09 Rivers might struggle.
06:11 They could be bursting their banks in some places.
06:13 There could also be some surface water issue because the rain is going to be pretty intense
06:17 at times.
06:18 I mentioned that there's some uncertainty as to the position of this rainfall.
06:22 And in fact, if you watched my week ahead forecast that went out on Monday on YouTube,
06:26 you'd have seen that the position of the rain that I just showed you is quite different
06:30 from what I showed you yesterday.
06:32 That being said, I did talk about the uncertainty then.
06:35 However, we are starting to get a better idea as to what is to come.
06:39 But if I try to show you the uncertainty in some way, and this is Met Office data showing
06:45 36-hour rainfall from midnight on Wednesday morning until midday on Thursday.
06:50 And I have three different model runs here.
06:52 So on the right-hand side, this is the model run from 18Z, 18GMT on Monday.
06:59 So this is when the model was started at 6 o'clock in the evening on Monday.
07:03 In the middle is the model run from midnight last night.
07:06 And on the right-hand side, we have the model run from 6 o'clock this morning or 6GMT this
07:12 morning.
07:13 So there are some slight differences in as much as older model runs keep the wettest
07:17 weather a little bit further east, whereas the more recent model runs have the rain a
07:22 little bit further west.
07:23 And it's really across parts of North Wales into the West Midlands where this model run
07:28 is suggesting we'd have a greater chance of seeing those highest rainfall totals and so
07:33 where we're most likely to see some pretty significant impacts because of the heavy rain.
07:38 So there is some uncertainty.
07:39 But bearing in mind the southward extent of the rain has changed a little bit comparing
07:43 the model runs.
07:45 The older model run from yesterday really just keeps southern areas not particularly
07:50 wet, largely dry, but a very different story in the more recent model run has more rain
07:55 pushing its way into southern parts.
07:57 And that all plays a part in the warnings that we're issuing and we're going to be issuing
08:01 and updating.
08:03 But another way that I can show you the uncertainty is if I look at Met Office data showing the
08:07 probability of greater than 50 millimetres of rain as we go through Wednesday and then
08:12 also Thursday behind me here.
08:13 If we look at Wednesday first though because it's most interesting, you can just about
08:17 see the greens highlighting where greater than 50 millimetres is likely.
08:22 And it's over a fair chunk of the UK or a fair chunk of England at least and then some
08:27 parts of North Wales.
08:28 That's where we have the greatest chance of seeing more than 50 millimetres.
08:32 By Thursday the chances are really over parts of Scotland, perhaps Cumbria too, but less
08:36 likely, less of a cause for concern.
08:38 It's still going to be a wet day on Thursday, but I don't think it's going to be as wet
08:43 or as impactful as on Wednesday.
08:46 If we compare for the same data but this time using ECMWF, so the European Centre for Medium-Range
08:51 Weather Forecasting and their position of where they're suggesting 50 millimetres is
08:56 likely is slightly different.
08:57 You can see it's not as far west as the Met Office model has it.
09:01 Again, looking at Wednesday on the left-hand side here and it's still suggesting that there
09:07 is a chance that we could see some significant amount of rainfall, but the position is slightly
09:11 different.
09:12 Again, Thursday showing over parts of Scotland most likely to have some very wet weather
09:16 then.
09:17 So, I showed you all this to highlight that there is still a bit of uncertainty exactly
09:22 where we're going to have some very wet weather.
09:24 I'm confident it is going to be a wet day for many parts of the UK.
09:29 We're getting into better agreement that there will be this relatively deep air of low pressure
09:34 coming across the UK and it's got a lot of water, a lot of rain mixed in with it.
09:38 And so, it really is going to be an unsettled picture.
09:40 But exactly where we're going to see the heaviest rainfall, there is still some uncertainty.
09:46 Models are starting to come more aligned suggesting over North Wales and perhaps into the West
09:51 Midlands, that's where we could see the greatest impacts, but they aren't definitely set in
09:57 stone.
09:58 The rainfall just isn't, hasn't been firmed up just yet.
10:02 We do have some warnings out.
10:03 I'll quickly go through today's.
10:04 You can see various thunderstorm warnings across Northern Ireland, South West England,
10:08 South East England and into Wales.
10:09 But let's start ahead to tomorrow's warnings and we have a fairly large yellow warning
10:14 across many parts of Northern England, into the Midlands and North Wales and then another
10:19 one across a large chunk of Scotland.
10:21 But I won't spend too long on these because these warnings are likely to get updated as
10:27 we go through Tuesday night into Wednesday.
10:30 We may need to stretch this warning a bit further south.
10:33 So even if currently you aren't in that yellow warning area, there's still a chance that
10:39 you could see some heavy, impactful rain as we go through Wednesday.
10:42 We may need to, just to go back to this chart that I showed you earlier, we may need to
10:46 cover not just for the rain anyway, for the thunderstorms both at the top and tail of
10:51 the country as well.
10:52 So there is going to be some heavy, impactful rain for quite a few places.
10:56 And like I said, even if you're not currently in a warning area, you may be still at risk
11:02 of seeing some heavy rain.
11:04 And so do stay up to date with the warnings.
11:07 You can do so on our website, on our app.
11:09 Check out our YouTube, we'll be updating that with videos, etc.
11:12 Informing you of where we most likely see the impactful rain.
11:16 Things we need to bear in mind of when we're looking at heavy, persistent rain.
11:20 Obviously, there could be some flooding around, but there could also be some travel disruption,
11:24 delays to rail, the rail network, buses, etc. and very difficult driving conditions.
11:30 If you are planning to travel, particularly tomorrow when we have the heavy, persistent
11:34 rain across parts of the UK, then do be aware that there will be very difficult driving
11:42 conditions.
11:43 Your journey will take longer.
11:44 Allow extra time and please just drive accordingly to the difficult conditions that are there
11:49 in front of you.
11:51 So I think I've covered the next few days in enough detail for now.
11:56 But just like I said, do stay up to date with the warnings because they are going to be
12:00 updated, tweaked and more added as we go through the next few days.
12:06 But let's move on and what happens thereafter.
12:09 And I showed you already, we have that low pressure system coming through as we go through
12:13 into Wednesday.
12:15 And then that eventually clears away towards, well, it kind of fills and then clears away
12:20 towards the northwest as we go through towards the weekend.
12:24 And then there's sort of a transient ridge of high pressure building for a time as we
12:29 go through into Saturday.
12:31 It's not the greatest of high pressure at all, but it does look like the weekend is
12:36 going to get off to a quieter start, particularly after the very wet weather that we've had
12:41 through the middle to latter part of the week.
12:44 And so Saturday actually looks like a fairly decent day for many places.
12:48 There's a lot of fine, if not sunny weather around, although a bit of rain starting to
12:52 push its way in from the west, particularly perhaps affecting Northern Ireland, Republic
12:55 of Ireland, maybe Cornwall as we go into the afternoon.
12:58 But for many, it's actually looking largely dry on Saturday.
13:01 That may not necessarily last until Sunday because we are going to see that feature then
13:04 coming in from the west and so a bit more showery perhaps.
13:08 It's going to break up a bit.
13:09 So I think there's a good chance that many of us will see some showery outbreaks on Sunday,
13:13 perhaps something a bit more persistent pushing into western parts behind those showery outbreaks.
13:17 As we go through Sunday, but definitely Saturday at least looks largely fine.
13:22 And actually across eastern parts of the UK, it doesn't look too bad on Sunday either.
13:27 There could be some decent dry and rather warm weather to be had as well.
13:32 Worth bearing in mind temperatures.
13:33 It's warm at the moment.
13:34 Well, it has been warm recently.
13:36 They are starting to dip down and with the very wet weather we can expect through Wednesday
13:41 in particular, it's going to feel more unpleasant.
13:44 It's not going to feel as warm as it has done recently.
13:47 But on Saturday, I'm expecting some decent warmth.
13:50 So it's going to feel pretty warm in any sunshine too.
13:53 And in fact, I won't show you it now, but it's a bank holiday on Monday.
13:57 But I don't think anyone's told the weather in as much as there are some tentative signs
14:02 that Monday could be a largely fine day across many parts of the UK.
14:07 Obviously, uncertainty does increase as we get further ahead.
14:11 So watch this space.
14:12 But tentatively, I'm optimistic that bank holiday Monday could be quite fine.
14:18 Right.
14:20 Beyond that then, there are no major signs for anything as we go through next week, probably
14:25 a bit more unsettled towards northwestern parts of the UK, a little bit more settled
14:29 towards the south.
14:31 I do have more information on that on our 14-day outlook, which will be available on
14:35 our app later on this afternoon into the evening, perhaps it might go up.
14:39 So do check that out if you want to know more information about what's going to happen as
14:43 we head through the very end of May and into June.
14:45 Now, I think that's everything that I want to talk about in terms of the forecast data.
14:50 But I did want to show you some statistics, some early statistics about May so far.
14:56 Thank you to Aidan McGiven, my fellow presenter, because he highlighted some of these stats
15:01 to me.
15:02 But I thought it was interesting that if we look at the rolling mean temperature so far
15:08 this month, and this is the cumulative, so it takes every day into account up until this
15:13 point.
15:14 And currently, if you've not seen this chart before, I will kind of explain it.
15:18 The black line in the middle, that's the average for May.
15:20 And you can see it changes as we go through the month.
15:23 The orange line at the top is the record for that stage in the month.
15:29 And then the blue line with the orange shaded bit below it is this May.
15:33 And so what you can see is this May, the blue line is currently well above the record in
15:40 terms of mean temperature.
15:41 So, so far, it is significantly warmer at this stage in May, taking the whole of the
15:47 month into account so far, than it ever has been on record.
15:52 And what is very interesting is, I mean, I said it's going to be a little bit more unpleasant,
15:57 a little bit fresher with the unsettled weather to come, but then some decent warmth again
16:01 as we go through this weekend and actually next week, temperatures look like they're
16:06 going to be, if anything, warmer than average.
16:09 But because of how much warmer than we are compared to the record, temperatures would
16:15 need to be 0.5 degrees below average through the rest of this month in order for us not
16:22 to have the warmest May on record.
16:25 So it's definitely not a guarantee yet, but it's pretty likely that this is going to be
16:30 the warmest May on record.
16:32 And interestingly, so I was looking at mean temperatures, that takes into account the
16:35 temperature throughout the whole day.
16:37 But interestingly, if you look at the maximum temperature, yes, again, we're still above
16:42 the record, but not by a significant amount.
16:45 And also if we look at minimum temperature, again, we're above the record, but not by
16:50 as significant amount.
16:51 So I think, well, I'm trying to deduce, and this may be wrong, but I'm trying to feel
16:56 that maybe, particularly in May, you often get your warm sunny days, your warmer sunny
17:01 days with lots of clear blue skies.
17:03 But then because of the time of year, that would allow for some chilly nights.
17:08 And so you don't always necessarily get your highest maximum temperatures on the same years
17:12 as you get your highest minimum temperatures.
17:14 Obviously, there'll be some correlation because warm days, the temperature can't drop a huge
17:18 amount.
17:19 But the point being, it's semi-unusual for it to be so much warmer than average and,
17:25 in fact, record-breakingly warm both by day and by night.
17:29 And so that's why when you look at the mean temperature, the difference compared to the
17:32 previous record at this stage in May is so large.
17:35 But like I said, there's a very high chance that it is going to stay above the record
17:41 through the rest of the month.
17:43 And this is likely to be the warmest May on record.
17:46 Watch this space, though.
17:47 We will, of course, update you as we get nearer the time.
17:49 The last thing then that I wanted to leave you with is a similar chart, but this time
17:53 for cumulative rainfall.
17:54 We've had a lot of rain so far this year, even through the start of spring.
17:58 Most months have been wetter than average.
18:00 But actually, May so far has been drier than average and by a fair chunk at the moment.
18:07 We do have some pretty wet weather to come through the next few days, so that will lift
18:10 this line up.
18:11 But, you know, watch this space as to whether or not May stays drier than average.
18:17 But at the moment, it is.
18:19 And do you know the last time we had a drier than average month?
18:23 It was actually January, but it was only slightly drier than average.
18:26 I think it was around 97% when you look at the U.K.
18:29 And in fact, England, for example, was ever so slightly wetter than average.
18:33 But we have had so much rain recently and so May has been a breath of fresh air in many
18:38 respects from that point of view with something a little bit drier instead.
18:42 Now, thank you very much for joining me for the deep dive.
18:46 I do hope you've enjoyed it.
18:48 If you have, hit the like button, share it with anyone who may think – find this interesting
18:52 – particularly the detail about the wet weather that's coming on Wednesday.
18:56 If there's anyone who you think might be impacted and needs to know anything that I've been
19:01 through today, then please do send them our way.
19:04 Leave a comment.
19:05 I will be answering some of the comments.
19:06 I'll be live in the comments section when this first goes out on YouTube, answering
19:10 some of the questions.
19:11 And I will be trying to help anyone who's maybe a bit concerned about the very wet weather
19:16 that we have coming up.
19:17 Like I said, do stay up to date with the warnings as we go through the next 24 hours or so as
19:22 they are going to get tweaked.
19:24 But that's it for me.
19:25 And you will be here tomorrow with the 10-day trend.
19:27 And I'll see you again soon.
19:28 Bye-bye.
19:28 Bye-bye.