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This is the Met Office UK Weather forecast for the next 10 days 21/01/2026.
A powerful and south-shifted jet stream will come up against cold air to the east during the next ten days with interesting consequences.
Bringing you this 10 day weather forecast is Aidan McGivern.
A powerful and south-shifted jet stream will come up against cold air to the east during the next ten days with interesting consequences.
Bringing you this 10 day weather forecast is Aidan McGivern.
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NewsTranscript
00:00Hello and welcome to the Met Office's 10-day trend. There has been a lot of interest in
00:04the weather next week. And whatever your preferred weather outcome for next week, it's safe to
00:10say that it is looking very interesting, if nothing else.
00:14And to explain why and to set up this week's 10-day trend, I thought I'd look at the much
00:19bigger picture and talk about the two dominant forces that will determine the UK's weather
00:24during the next 10 days and perhaps beyond. Those two dominant forces include cold air
00:30to the northeast of the UK, which will become a factor during the next few days. That cold
00:36air across Scandinavia extending into the North Sea by the weekend. And the UK getting a taste
00:43of it. Not the very coldest air which will remain to the northeast, but something a little colder,
00:48especially for the north and east of the UK by early next week.
00:52Now, if this was the only factor determining the UK's weather through the next 10 days,
00:57my job would be easy. I'd talk about very cold easterly winds, snow showers and much below
01:03average temperatures. But it's not the only factor determining our weather through the
01:09next 10 days. Some computer models have been underestimating another important factor determining
01:17the UK's weather into next week. Those computer model simulations have shown cold easterly winds
01:22throughout next week, whilst they've been underestimating the depth of cold air
01:26elsewhere on the planet. And that is across North America, where, watch this as it evolves,
01:33very cold air will move through Canada into parts of the USA. Maximum temperatures by the end of the
01:39weekend across New York of minus 7 Celsius. And that is the other key force determining our weather
01:49weather through the next 10 days. Not because we're expecting that cold air to make it across
01:54the Atlantic and affect the UK. Regular viewers of the 10-day trend and the deep dive here at the
01:59Met Office will be aware that when we get these cold outbreaks across North America, similar thing
02:05happened at the start of December, what actually happens is they come up against milder air further
02:09south. We get an enhanced temperature contrast, and that only goes to fuel a powerful jet stream.
02:16So now we have a powerful jet stream coming out of North America, making its way across the North
02:21Atlantic, but on a south shifted path. So further south than normal for the North Atlantic and Northwest
02:29Europe. And as a result, we've now got powerful jet stream and deep areas of low pressure coming in from the
02:36Atlantic, bringing wet and windy weather through the weekend and into next week, coming up against
02:42colder and drier weather to the north east of the country. And that sets it up because that means that
02:49the weather isn't straightforward mild wet and windy, which we often get in the winter, but nor is it
02:55straightforward cold easterly winds. Now, you'll find some model simulations that show both of those outcomes,
03:02but in reality, I suspect it'll be somewhere in between a mix of both at different times, through the
03:09next 10 days and for different places. In other words, it's complicated. But another consequence of this
03:16powerful jet stream coming up against the cold air is that these weather systems are going to slow down. And
03:24that is important because the rain bands will slow down and we'll see significant rain in places. So as
03:32you can see, the first low that is affecting us during the next few days, that's not moving west to east
03:39in a nice swift fashion. It slows down. The winds, in fact, tilt to become more south easterly. So as these
03:46bands of rain move in from the Atlantic, spells of rain across many parts of the UK through Thursday and
03:52Friday, we are particularly concerned about eastern Scotland because the winds from the southeast are
03:56strengthening. All this moist air is being dumped over the hills and we're going to see some significant
04:01outbreaks of rain accumulating over eastern Scotland, 60 millimetres widely, 100 or more millimetres over
04:09hills. Now, through Friday, it will turn colder and as a result, some of this rain will become locked up
04:15as snow. So that's one saving grace. That's mostly above 400 metres, however, and there will be significant
04:21rain at lower levels. This shows the total rain through Wednesday, Thursday and into Friday,
04:25three-day accumulations across central and eastern Scotland. Warnings are in force. There is the risk
04:32of flooding. Head to the Met Office website for the very latest on these warnings. But it's not just
04:37eastern Scotland where it's wet. Across much of the UK, 50 millimetres or more through Wednesday,
04:41Thursday and Friday with these spells of rain or heavy showers affecting many places, especially the
04:46south and the west. And that's because these systems are also going to bring very unsettled weather
04:51through the south and the west of the UK. You can see from the bright colours there, heavy downpours
04:55into south-west England, south Wales, Northern Ireland as well, drier for east Anglia perhaps,
05:01and the north-west and north of Scotland. But it's safe to say it's going to be very unsettled
05:07across the UK through Thursday and feeling a little colder in the east as well as those south-easterly winds
05:13strengthens, still in the double figures in the south. The rain perhaps easing off for a time in
05:17the south and south-west of England as we go into Thursday evening. But the next low starting to get
05:23its act together and that's going to bring another spell of wind and rain by the start of Friday
05:29into the south and south-west of the UK. So South Wales, south and south-west England, a wet and windy
05:34start to the day on Friday. Some heavy rain in places, drier further north through central parts,
05:39further persistent spells of rain like I say in eastern Scotland, but snow above 400 metres, some
05:45significant snow accumulating. And then the first band of rain moves north, further blustery showers
05:51into the south-west and you can see the tightly packed isobars there, risk of coastal or even inland
05:56gales at times, especially for Cornwall and parts of Devon. So Friday, a very mixed bag, blustery,
06:04outbreaks of rain and showers feeling a little colder in places as well. You can see the impact
06:10of the change in wind direction in the north-east of the UK. And indeed, if we go through to the
06:15weekend, these systems are really quite slow moving. The low pressure barely budges, but it does fill
06:21thankfully, and it tends to slowly move away. And we'll see those south-easterly winds bring
06:28increasingly cold air in on Saturday and more especially into Sunday. Now, by Sunday, with that
06:37cold air in place and easterly winds, it is going to turn a bit drier. But Saturday starts off with
06:42further heavy showers and gusty winds, especially in the south and south-west, further strong winds in
06:47the north-east of the UK as well, especially eastern Scotland, north-east England, rain at lower
06:52levels, snow over hills. In between, some drier weather, Northern Ireland, parts of Northern England,
06:57East Anglia, Western Scotland for example, but feeling cold in the east, especially five or six
07:02celsius. And then turning even colder as we go into Sunday with further showers into the north,
07:08west and the far south, gusty winds as well. In between, the Midlands, north-west England,
07:13south-west Scotland, some sunshine, so not that unsettled with some bright skies out there and
07:20mostly dry. The showers turning more to sleet and hill snow across the north-east of the UK by this
07:26stage, but drier weather in between. Rain showers from Northern Ireland, the south and south-west of
07:31England and parts of Wales feeling colder, especially in that increasing east to south-easterly wind.
07:38Now, I've set the scene for the start of the weekend and into the end of the weekend,
07:45we've got the easterly winds, the cold air making further inwards further west.
07:50But we've got the jet stream and those Atlantic lows gearing up to come in, containing milder air
07:57but also containing outbreaks of rain. And this is the first clash of the Atlantic lows and rain with
08:05the cold air coming in from the north-east. Let's put the rain on and you can see a band of heavy rain
08:11turning up first thing Monday across Northern Ireland, Wales and the south-west. But as that bumps
08:16into the cold air it will mix, it may well turn to snow in places. And that's the first question
08:21mark into next week. Where exactly is it going to turn to snow? And the answer to that depends on
08:28the exact orientation of the low pressure that's carrying it and subtle changes in the latitude of
08:33the low. And its orientation will determine where, if anywhere, we see snow on the leading edge of this
08:41rain. Now, the control run of the European model has the low slightly further south than the Met Office
08:48run and the winds are slightly more south to south-easterly. So there's a greater extent of
08:54cold air mixing with the rain and a greater chance of some snow, at least initially before it turns back
09:00to rain, across parts of central southern England, the Midlands and Wales and more especially further
09:06north across northern England and Scotland, especially over the hills. If I run that through,
09:11you can see how the low doesn't push across the UK. In fact, it disappears to the north-west and we
09:18keep that colder south-easterly feed at least for a time through Monday and Tuesday. So in this scenario,
09:25yet there could be some significant snow in places, at least before we see the rain set in. But that's
09:32not the only scenario. We run the computer model multiple times and we adjust the starting conditions
09:40to account for chaos theory. The reason we do that is to explore what-if scenarios. One example in this
09:45case is what if the cold across North America isn't quite as cold? Well, in that case, the jet stream is
09:50not quite as powerful, in which case the low pressure doesn't quite dominate across the UK and the
09:56cold easterly winds would dominate instead. What if the cold across North America is stronger? Only
10:04slightly, but that would lead to a more powerful jet stream and a greater chance of these lows bringing
10:10wet, windy and milder weather in from the Atlantic. So when we run these computer model simulations,
10:17very tiny changes at the start can have markedly different effects in a few days' time. Now here we're
10:23comparing two different simulations of the European model. One of them starts on top there with more
10:29of an easterly wind. The other starts with a southerly wind. Both have low pressure arriving from the
10:34Atlantic, but in this case we'd see snow stalling and disappearing again from the southwest. In this
10:43scenario you can see warmer colours across the map. Southwesterly winds by Tuesday. There's not a great deal
10:50of difference between the two, but one of them is a much more wintry scene than the other. Southwesterlies
10:56versus southeasterlies. Again, go right back to the start. The only difference is possibly the extent of
11:03the cold across North America. And this sums it up. When we run the model many, many times we come up
11:09with the most likely weather patterns and the second most likely and third most likely and so on.
11:13This isn't just the European model, this is multiple models and this graphic shows the most likely
11:18weather pattern for next Tuesday. 49% chance. We've got low pressure sitting to the west,
11:24outbreaks of rain, very wet in the south and we've got milder air. This shows where temperatures are
11:31above average in this scenario in the south. Still a little below across the north, but many places
11:36closer to average. But the second most likely weather pattern, 33% chance. We've got colder east of
11:43these below average temperatures across the whole of the UK. And it's those two scenarios that really
11:50dominate proceedings through next week. The first one, low pressure, is this colour. The second one,
11:56easterly winds, is this colour. And you can see how those are the two main themes right the way through
12:01to the following weekend. Because it's not just that first low, there's another low that's expected to
12:06arrive mid-week from the Atlantic. Here's another two model simulations starting on Tuesday. First low,
12:14pictured here, but there's another significant low waiting in the mid-Atlantic. Now, watch what happens
12:20to this low. Top graphic, this is the European model control run, shows that low pressure coming along
12:28and on a slightly more north-facing track of the jet stream, the winds are pointed more to the south and
12:35south-west by Thursday. This low is slightly further south, but look at the difference. Really quite
12:42cold over the UK. In this scenario, easterly winds return. Again, possibility of snow on the leading
12:47edge of that low. But in this scenario, much milder air with south-westerlies instead. So really quite
12:55big consequential differences at the end of these two simulations, even if they both start with very
13:01similar conditions. I suspect something in between will experience, but it all depends on the latitude
13:09and the depth of these lows coming out of the Atlantic as they bump into colder air to the north
13:15and east. And most likely, we'll see wet, windy, milder weather at times towards the south-west,
13:22colder, drier weather at times towards the north-east, and somewhere in between always the chance
13:26of some snow. Of course, we'll firm up on the details of the latitude and the depth of all these various
13:32lows as we get closer to next week. But for now, that's all for me. Bye-bye.
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