Monday evening forecast 18/09/2023
18 September - National weather forecast presented by Alex Burkill.
Category
🗞
NewsTranscript
00:00Hello again. We have some very wet and windy weather set to arrive across the UK as we
00:05go through Monday night into Tuesday. Starting off looking at the bigger picture, and here's
00:10the front that brought heavy rain earlier on Monday. That's now clearing towards the
00:14east with showers following in behind. But our attention has already turned to this area
00:20of low pressure out in the Atlantic. This is the remnants of what was Hurricane Lee.
00:25Because we have an active jet stream currently in the Atlantic running across to the UK,
00:30that low is going to quite quickly make its way towards us. There will be some weather
00:34systems ahead of it bringing some very wet weather. But then as that low gets closer,
00:38we're going to see even more wet weather arriving in association with this frontal system. And
00:43look how tightly packed those isobars. It's really not just going to be wet, it's going
00:47to be windy as well. Back to the here and now though, and here's that front that I mentioned
00:52earlier. You can see not only did it bring some rain, but it also formed the boundary
00:56between some warm humid air in the east and also something a little bit cooler, a bit
00:59fresher and less humid, which has now crossed its way into the UK. As we go through the
01:05rest of Monday, you can see the heavier rain towards the east clearing away, though lingering
01:09for a time across parts of Shetland in particular. Plenty of showers following in behind, though
01:14some clear spells to start the night, holding on to those clear skies towards far eastern
01:18northeastern parts of Scotland. Otherwise, though, turning increasingly cloudy and wet
01:23and windy as this system approaches, particularly across parts of Northern Ireland, Western
01:27England and Wales and South West Scotland too. Because of the cloud and the rain, after
01:32perhaps a chilly start to the night, temperatures are going to rise as we go through the early
01:36hours of Tuesday morning. So for many, by the time we hit dawn, it's actually going
01:40to be pretty mild, most places in double figures. A little bit chillier, though, where we have
01:44those clear skies across northeastern parts of Scotland. It is going to be a wet day on
01:49Tuesday, some heavy and persistent rain spreading its way from west to east, most likely seeing
01:54those totals building up across parts of northwest England and western Wales. Most places, though,
01:59having lots of cloud and some strong winds, perhaps the greatest chance of some bright
02:04spells across far northern parts of Scotland. But even here there will be a scattering of
02:08showers and still some strong winds with coastal gales possible. Like I said, we are going
02:12to see some totals building up, particularly in this area where we have a yellow warning
02:17in force. We could see totals of 50 to 100 millimetres of rain quite widely, perhaps
02:21locally 150 to 200 millimetres of rain for some places. Though, worth bearing in mind,
02:27this warning is valid for 36 hours from 6am Tuesday to 6pm Wednesday. And it's most likely
02:33over the Welsh mountains where we're going to see those highest totals. Nonetheless,
02:37some disruption is quite likely with some localised flooding in places too.
02:43Temperature wise on Tuesday and with the cloudy wet weather, although on paper these temperatures
02:47are near normal for the time of year, it's going to feel much cooler than that. It's going to feel
02:51pretty unpleasant in that unsettled weather. Later on on Tuesday, this band of rain then is going to
02:57sweep its way east north eastwards, but further wet weather then arriving from the west, some
03:01heavy pulses of rain arriving in association with that frontal system that I showed you at the start.
03:07So a cloudy, wet and windy picture as we go through Tuesday night into Wednesday morning.
03:12As a result, again, temperatures aren't going to drop much. Most places holding up into the
03:17mid-teens in the towns and cities, these temperatures are close to what you'd expect
03:21during the daytime. But factor in the unsettled weather. If you are out in it, it's not going to
03:26feel mild, it's going to feel pretty unpleasant. As we go through Wednesday itself then, and for
03:31many it's another cloudy, wet day. Further spells of heavy rain after spells of heavy rain continuing
03:37then across particularly northwestern parts of England, western Wales, which is why the warnings
03:41in force, but also some southwestern parts of Scotland could see totals building up as well. So
03:46worth bearing in mind, there could be some impacts there. By Wednesday afternoon, this heavy band of
03:50rain is likely to be across more eastern, central, southern parts of England. And while there will be
03:56something a little bit drier following it behind, you can see that rain wraps around. So some heavy
04:00rain could be pushing into far northwestern parts of Scotland. And elsewhere, there'll be plenty of
04:05showers, a rash of showers. And again, although these will rattle through quite quickly on those
04:09strong winds, they do bring the risk of some hail, some thunder and some intense downpours too.
04:15Once more, temperatures, well, they're near normal for the time of year, highs in the low 20s towards
04:19the southeast. But you still have to factor in those strong winds and that heavy rain. It is
04:24going to feel quite unpleasant at times. As we look ahead to the rest of the week and the unsettled
04:29weather kind of sticks with us. It is going to turn a little bit cooler perhaps. And although
04:33there will be a brief drier spell later on Friday, I think it is just going to be that quite brief.
04:38Adrian has more information on the week ahead forecast in the week ahead. And you can keep up
04:43to date with the full forecast wherever you are on our social media channels, our app and our website.