- 4 hours ago
This is an in-depth Met Office UK Weather forecast for the next week and beyond 05/05/2026.
Whilst the weather in the UK is calmer, across South Africa it’s going to be exceptionally wet for the next few days.
Bringing you this deep dive is Met Office meteorologist Alex Burkill.
Whilst the weather in the UK is calmer, across South Africa it’s going to be exceptionally wet for the next few days.
Bringing you this deep dive is Met Office meteorologist Alex Burkill.
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NewsTranscript
00:01Exceptionally heavy rain in South Africa. A look back at April for the UK and also
00:06frost in May. How unusual is it? Lots to cover in this week's Deep Dive. Thank you for joining me.
00:12I'm Alex Burkill, presenter and meteorologist and coming to you as we do every Tuesday from
00:17our headquarters here in Exeter. If you've watched one of these Deep Dives before, you'll know that
00:22we do answer some of your questions and your comments, so do get them coming in. Maybe I'll
00:27answer them this afternoon or perhaps in the Weather Studio Live on Friday. Annie and I will be back
00:32then. If this is your first Deep Dive you've ever seen, where have you been? Make sure you hit that
00:37like button and also make sure you're subscribed so you never miss one of our updates. But let's get
00:43cracking. And currently the weather across the UK, it's a bit meh, it's fairly quiet, so let's first
00:49head further south and across parts of South Africa. So actually across central parts of Africa,
00:56where there's some rain, heavy seasonal rain, but nothing too out of the ordinary. It's across
01:01South Africa where we have some exceptional rain forecast through the next couple of days. If I
01:07run this sequence through and actually if I put the winds on as well, you can see an area of
01:12low
01:12pressures developing just to the southeast. And with the winds, remember, coming round in a clockwise
01:19direction in the southern hemisphere, we're dragging in some warm and moist air and that's going to wrap
01:25around brings some strong gusty winds and also some exceptionally heavy rain. We're expecting
01:31well in some quite widely 75 to 150 millimeters in just a day or so and more than that in
01:39some places.
01:40And when you add up a few days, we could see three, four hundred millimeters of rain in some places,
01:45which
01:45when you factor in that the average may rainfall for this part of the country, part of the world is
01:52only around 40 millimeters. It is going to be a very wet event indeed. So what is happening? Well,
01:59let's look first of all higher up and here I have the 500 hectopascal geopotential height. So 500
02:08hectopascals, it's around five and a half, 5.9 kilometers up. And what we're looking at as is the height
02:14that you have to go to get to that pressure reading. And this chart's from Polar WX and it's also
02:22comparing it to the record. And so what we can see is there's some very low pressure for that high
02:29up.
02:30So it's a very deep cutoff upper vortex that's developing higher up in the atmosphere. And it's
02:37well, it's particularly close to record breaking just near the Namibia border. You can see those
02:43blue shades. So we have this cutoff upper low. And then the influence of that is feeding its way
02:49southwards. If we look slightly lower in the atmosphere, now we've got the 700 hectopascal
02:54geopotential height. This chart is from Alicia and Bentley from her website. And what we can see,
02:59we still have this cutoff vortex. And then that's dragging in this plume of warm, moist air southwards.
03:07And then that's wrapping around that cutoff vortex. And then as that's shifting its way eastwards,
03:14we still have this lingering occlusion that's feeding into South Africa, which is why we're
03:20going to see those rainfall totals building up because we get then low pressure developing near
03:24the surface that I've just shown you, bringing such high amounts of rain and some very
03:29strong damaging winds. But let's look at how wet and how windy it's going to be. So here I have
03:35some
03:35meteograms from ECMWF. And if we look at the rainfall, well, Wednesday sticks out like a sore thumb.
03:42The middle bound for Wednesday is around 117 millimeters. This is for Jabotina in the Eastern
03:48Cape. And yeah, 117 millimeters in just a day. Remember, I said the average is around 40 millimeters
03:56for the whole of May. So it is going to be very wet indeed. Now, obviously, there are some variations.
04:03Some of the model members from ECMWF had even more than that, more than 200 millimeters. Some had
04:08significantly less. But if we look at that 50th centile, it's going with around 170 millimeters. So
04:15let's look at that in a different way. And we still have our charts from ECMWF. But here's some graphs
04:23that you may not have seen before. And what we have are various different model runs. Again,
04:28looking at rainfall for Jabotina as we go through this Wednesday. So 24-hour rainfall. The red line
04:36is the most recent model run from ECMWF. So it was the midnight last night. The purple line is the
04:42midday from yesterday. And then previous model runs going back in the blues. What we have in here,
04:49the black line is the climate model based on, it's only 20 or 30 years, I can't remember,
04:55the climate model for Jabotina when looking at rainfall. So the vast majority of the time,
05:00it's dry. Whereas there have been some instances where they have had rain, but the most extreme
05:06from the climate model is only around 33 millimeters in a day. Whereas if we look at again,
05:14the 50th centile for Jabotina for the forecast from the latest model run. And you can see,
05:19like I mentioned earlier, it's around the 170 millimeter mark. So that's more than five times
05:26the most extreme, wettest day at this time of year that we've had from that climate data set. So it
05:33is
05:33going to be very wet indeed. There is some, there is some spread. So it may not be as wet
05:39as that,
05:39but it could potentially be even wetter. And that is then going to have a major knock on effect
05:45to the river catchments. There's higher ground here. So as that wet weather pushes up and hits
05:52the orography, it's going to lead to this intense rainfall. And then very quickly, we're going to see
05:57the water rushing down those hills. And we're going to see some major impacts as a result.
06:02This is our Glowfest data looking at river catchments and showing the sort of return periods
06:08that we're looking at. The different color triangles showing the different length of
06:13return periods with the purples being greater than 20 years. But for some places, we're looking
06:19at a return period in excess of 100 years. So it is really going to be very, very impactful.
06:26The numbers that are showing are the number of members that are in agreement with this return
06:31period that's going. So very high confidence for it to be a very impactful event with a significant
06:37amount of rain. And then that's going to cause some major problems when it comes to the rivers.
06:42And we're likely to see some significant flooding. Worth bearing in mind that there was a similar event
06:49last year, a bit later on in the year, but last year, and I think it was a bit further
06:52east,
06:54that led to around 100 fatalities. Now, that area was slightly more populated, but also slightly more
07:02used to heavier rain than this part of South Africa, eastern parts of Western Cape and western parts of
07:10Eastern Cape. And so it is possible that we could see similar level of impacts in terms of fatalities,
07:19because it's not just the immediate impact in terms of the high rainfall totals and that flooding
07:25that's likely to occur. There's also the ongoing issues that will happen because livestock agriculture
07:34could get washed away and really wiped out because of how much rain is coming through.
07:38And then it's not just the rain that we need to be aware of. There's also some very strong winds.
07:44This is a similar chart to what I showed you earlier, but this time looking at gusts. And if we
07:50look at the
07:5050th centile for the latest model run, it's going with around 24 meters per second gusts for Jabotina,
07:57which is around 53, 54 miles per hour, which is very close to the most extreme, the 100th centile
08:05from that climate model date or climate data set. So it is going to be very windy as well as
08:11wet.
08:11These kind of strength of winds, they're enough to cause some major problems, power cuts and damage to
08:16property as well in that part of the country. So it is going to be very wet and also windy.
08:22And so no wonder we're concerned about the impacts that are expected across parts of South Africa
08:27through the next couple of days. After Wednesday, it does become less intense and it clears away.
08:33But nonetheless, it is still going to be quite wet for a little while and then drier towards the end
08:38of the week.
08:41Then let's look back at the UK because we are the Met Office for the UK after all. And it's,
08:48like I said at the start, a bit of a meh week in as much as we have high pressure
08:53to the west of us,
08:54low pressure towards the east and we're in between. And so, yes, there'll be some rain
08:58and there'll be some sunshine at times, but it's not looking stormy or anything like that.
09:02And it's not looking as bright or as sunny as it was last week or as warm. I'll come on
09:08to the
09:08temperatures in a second. But yeah, we have a fair amount of cloud, a bit of brightness at times,
09:13some outbreaks of rain. If we run it through, the rain's not especially heavy. Just a bit of rain
09:19coming through. We do have colder, clearer air coming in from the north as we go through tonight.
09:23But I mentioned that the rain's not especially heavy. However, I do want to focus in on the southwest
09:28as we go through tomorrow. Let's pause it here because if we zoom into southwest England,
09:34and we're likely to see an area of convergence here. And so that brings the potential for some
09:39heavy, perhaps even thundery showers to develop across, well, western parts of Devon, parts of
09:45Cornwall as well. So do watch out because they could be, yeah, like I say, heavy, thundery,
09:49could be a bit of hail and lightning mixed in with them and could be some heavy rain. Shouldn't
09:53cause too many problems, but just watch out for that. Some of the showers across eastern parts could be
09:57quite heavy as well. But most places actually through Wednesday having a lot of dry weather.
10:02And there's going to be some more dry weather to come as we go through the rest of the week.
10:06Also
10:06outbreaks of rain here and there, but shouldn't be too problematic. There's an area of low pressure
10:11to the north northwest of the UK as we go through Thursday, Friday's time. So that's going to bring
10:16some wet and windy weather here. But again, nothing too problematic. It's as we go into the weekend
10:22that our attention is turning to something towards the south of us. So we're likely to see
10:28a plume of something coming up from the south. So it is potentially going to bring something quite
10:34a bit wetter and also thundery as we go through Saturday and more so overnight Saturday into Sunday.
10:41So there's this first pulse of rain that comes through and then there's more wet weather feeding
10:46up from the south. So yes, potentially could turn a bit more unsettled as we go through this weekend.
10:51But with that, we are going to see a rise in our temperatures with warmer air coming in from the
10:57south. And we're seeing a rise in temperatures because before that, we're seeing a drop in
11:01temperatures. So we have colder air that's coming in from the north as we go through the next 24 hours.
11:08So I can show you that if we look at a couple of temperatures. Let's take London, for example,
11:12to begin with. And we can see Wednesday's maximum temperatures are down a few degrees compared to
11:18today's. It's going to be a little bit cooler than average for early May. But then we see a rise
11:23in
11:24temperatures as we go towards the weekend with that warmer air that I mentioned coming up from the south.
11:29But if we look further north and just picking somewhere over the highlands, for example,
11:34and temperatures, you know, for some at the moment are struggling to get much above freezing.
11:39And then it is rising, but only by a few degrees. So not particularly warm. But, you know,
11:44it's that the highlands of Scotland is not normally particularly warm at this time of year. But I did
11:50want to highlight that there is some frost around temperatures by night dropping a few degrees below
11:56freezing. And the question is, how unusual is frost at this time of year? And the answer is not
12:03especially. Now, here I have a map looking at the average number of days with ground frost in May.
12:11Now, ground frost and air frost are different. Air frost is when the temperature drops below freezing,
12:16the air temperature. And ground frost is when the ground drops below freezing. And at this time of year,
12:22compared to, say, early autumn, the ground has less warmth to it. So the similar air temperature at this
12:30time of year to early autumn would lead to a lower ground temperature than it would do in a few
12:37months time, because after the summer, the ground's got a bit more warmth in it. So you're less likely
12:41to get that ground frost than you would have been during the same setup, same air temperature at this
12:47time of year. But what you can see is, you know, particularly across northern areas, as many places,
12:5310 to 15 days of ground frost during an average May. The further south you go, and particularly for
12:58coastal parts, the fewer that you're likely to see as many places across parts of well. Devon and Cornwall,
13:04for example, only seeing a couple of days of ground frost in an average May. But another chart that
13:09my colleague Dan Holley, who's a regular participant on these deep dives he created for me, is looking at
13:15the average date of the last spring air frost. So now I'm looking at air frost, not ground frost.
13:22So the last air frost, the average date that we get. And as you expect, there's a trend from south
13:30to
13:30north. The further north you are, the later on in the year it is. So some places are well into
13:35June. In
13:35fact, I think there are a few places where the last air frost goes beyond June. And then I guess
13:42it
13:42becomes a bit tricky as to whether it's the last air frost of this year or the the first air
13:47frost
13:47of next year. So but what you can see is that, yeah, some places have the potential or the average
13:53air frost all the way through June. Whereas further south, and it's it's earlier on in the year, but it's
14:01not. Well, there are a fair few places which have air frost as we go through May. So the bluey
14:06colors
14:07indicating across parts of Wales and parts of the Midlands, even East Anglia and and then northern
14:13England and large chunks of Scotland. So but both the chart that I showed you before looking at the
14:17average ground frost and also this chart here showing you the the average date of the last
14:22spring air frost. It is clear that frost in May isn't that unusual, depending on where you are.
14:28It's definitely not unheard of. Some coastal parts towards the south, the average last frost is more
14:34so towards like, well, early March, even end of February, so much earlier on in the year. But
14:40that's what you'd expect. One thing that I did actually want to compare, however, was this is
14:45looking at the 1991 to 2020 average. If we look at the previous average set, so the 1961 to 1990,
14:53and there's quite a difference. It's not that unsurprising, but it is. Well, it's not unsurprising at
14:59all, to be honest, but it's quite interesting. When we look with our warming climate, it's not that
15:06surprising that looking at the 30 years before, the average date for that last air spring was later in
15:14the year than it currently is. And so you can see more places having their last air frost in May
15:20and
15:20a few places in Wales and northern England having it more in June, which was less of the case
15:25when we looked at the more recent data set. So the last air frost is getting earlier and earlier
15:31in the year, and that's because of our warming climate. But it's still tricky and problematic for
15:39growers, gardeners, for example, at this time of year when you do get a frost. Because with our warming
15:45climate, some flowers, some plants are coming out earlier in the year than they used to. And then when
15:51you get this frost, it can then kill them, it can cause them major problems. And so it's something
15:58for gardeners, growers to be really aware of that there's still the potential for some frost as we go
16:03through this week, because there is that chill before we see that rise in temperatures, that warmer
16:08air that's coming in from the south as we go through this weekend. Then it's May, as I mentioned a
16:15few
16:15times, and so we can now look back at April. It was touched upon on the Weather Studio Live with
16:20Alex
16:20Deacon and Aidan last Friday. But I can now give you a little bit more detail about what we saw
16:25in April just gone. And I think for many people, it will be remembered as being remarkably dry. But
16:31there was a large contrast when you look at rainfall across the country, parts of the northwest,
16:37western Scotland. Well, here it was actually wetter than average. But yes, very dry indeed towards the
16:43southeast. And if we break it down into individual counties, and I think for Cambridgeshire,
16:48it was their second driest April on record. For Norfolk, the third, Bedfordshire, the fourth,
16:53and for Essex, the fifth driest April on record. And for England and Wales, it was, yeah, drier than
17:01average for sure, just across parts of Scotland, even western parts of Northern Ireland. It was a bit
17:07wetter than average. But it was a sort of a tale of two halves looking at the UK as a
17:13whole,
17:13rainfall wise, as we went through April. Now, this chart I have here, you may have seen it before,
17:19for similar months or climate projection or climate stats that we've had. And it's looking
17:26at the rolling rainfall totals through April just gone, and comparing them both to the average, which
17:32is the solid black line, and also the most extreme. So that the driest being the the blue line
17:37at the bottom, that's kind of counterintuitive, you kind of think those colours should be switched.
17:42But and then the the wettest being the the orange line at the top. And what the dotted line is
17:48April
17:492026. And the shaded area shows us where we are compared to that average line. And you can see that
17:54the beginning of the month wasn't particularly noteworthy, it was a bit wetter than average at
17:59times, a bit drier at times. And then it got wetter and wetter, and we were significantly wetter than
18:04average. Up to around the middle part of the month, near my birthday, the 15th of April,
18:10around then it suddenly became quite a bit drier. And then we didn't really see,
18:15looking at the UK as a whole, didn't really see a huge amount of rain thereafter through the rest of
18:21the month. So we went a fair few millimetres wetter than average to markedly drier than average. Oh,
18:28I've gone click the screen. And so then that's caused problems. We've gone much drier than average
18:34later on. And then by the time that we got to the end of the month, yes, again, emphasizing looking
18:40at the UK as a whole, not everywhere, but looking at the UK as a whole, it was quite a
18:46bit drier than
18:46average. Then one thing that I did actually want to just point out back to this chart, and I mentioned
18:51it before in deep dives. But this was basically the polar opposite, the reverse, in many ways,
18:58of what we had through much of winter. And it was similar through March, to be honest, in as much
19:02as
19:02we've had much drier weather towards the southeast so far this spring, but wetter than average weather
19:08towards the northwest. Whereas, yeah, during winter, it was the complete opposite to that.
19:12Wetter towards the southeast and parts southwest and Northern Ireland, and then drier than average
19:17towards the northwest. So that's kind of interesting how things even out, I suppose,
19:22when you look at several months, several seasons, and combine them. Then, as we often get when it
19:28comes to dry weather, you often get lots of sunshine. And for the UK as a whole, it was markedly
19:34sunnier than average. We had around 39 percent more sunshine than we do in an average April. And
19:40some counties, Dorset and also the Isle of Wight, had their sunniest April on record. So it was
19:46very sunny indeed. I'm sure most people are grateful for that. We've talked a lot about UV.
19:53The UV strength is getting higher and higher at this time of year. That's less of a problem this
19:58week with quite a bit of cloud around. But do, you know, be aware that, you know,
20:02the sun has some decent strength behind it and you can still burn through the cloud and still worth
20:07wearing sunglasses to protect your eyes. Then, before I go, one last thing when looking at April
20:122026, it was also warmer than average for the UK as a whole. If we look at mean temperature,
20:19it was around a degree warmer than average. Goes in line with our warming climate, I suppose.
20:24But yeah, around a degree warmer than that 1991 to 2020 average. But I wanted to break it down
20:29because if we look at maximum temperatures, it was even warmer than that. It was around 1.9 degrees
20:35warmer than average looking at maximum temperatures. But if we look at minimum temperatures,
20:39it was much closer to average. I think it was only around 0.4 degrees higher than average. And that
20:44goes in line with that sunny picture that I just told you about in as much as we had lots
20:49of clear
20:49skies. And, you know, during April, the nights are still quite long. And so you have a lot of time
20:56to lose that heat when there's not a huge amount of cloud around. So we still got some pretty chilly
21:01nights. And that's why our minimum temperatures weren't especially high compared to average. But then,
21:06once the sun comes out, as I mentioned, the sun has some decent strength already as we go through
21:10April. And so then we saw our temperatures rising. So it was warmer than average, particularly by day,
21:16and only slightly warmer than average by night. A large chunk of that was as a result of just
21:23how little cloud there was with lots of sunshine on offer, much, much sunnier than average.
21:29Well, thank you so much for watching this deep dive. I do hope you enjoyed it. Remember,
21:34as always, leave your comments, leave your questions, and we'll get to some of them
21:36on the Weather Studio Live this coming Friday. As I mentioned before, it's Annie and me.
21:40So we'll be back then at 12.15. You know that, of course. I'm sure you're a regular viewer.
21:47Alex Deacon will be here tomorrow with the 10-day trend. That'll be worth checking out. He'll have
21:51more information about that wetter, that warmer air coming up from the south as we go through this
21:57weekend. Hit subscribe, hit the like button. We love doing these videos. We love sharing our knowledge
22:03and our passion for weather, but we only get to do them if we're getting that interaction back with
22:09you. So do keep those comments, those likes coming our way, and then we can keep doing these videos
22:14for you. But thanks to you again for watching. I do hope you enjoy the rest of your day, and
22:18I'll see you
22:19again soon. Bye-bye.
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