Wednesday 27th September 2023

Warmer than normal with high pressure trying to take control – though not having its own way entirely.

Thanks to Tara for the photograph.

So the general picture for today sees Storm Agnes moving in – not really a story for us down here, the warmth from the continent is more notable.

It will be mostly cloudy for us today, though some bright spells are possible as the cloud should be quite thin at times. The bulk of the rain stays to our north-west, but the odd showery bit is possible – and probable during the evening. Becoming windy, though nothing unusual for us, and reaching around 21’C. A mixture of clear spells and cloud overnight, down to around 13’C.

Thursday will be fairly cloudy, but the cloud will be thin enough to allow for hazy sunshine. Temperatures a bit lower, around 18’C, maybe 19’C. Still breezy. Cloudy with some showery rain in the evening and overnight, a fairly warm night at around 15’C.

Some cloud still possible to start the day on Friday, but it will clear to leave good spells of sunshine – a bit of fair weather cloud, and perhaps some high-level cloud to make it hazy. Reaching around 20’C, or a shade under. Fairly clear skies overnight and chilly, down to around 7’C.

By Saturday we see high pressure rising from the south.

So we are looking at fine and settled weather, though sunshine is likely of the hazy variety due to a spell of rain to our west. Reaching around 18’C. Reasonably clear skies at first overnight, though likely clouding over later. Not chilly, though temperatures a bit uncertain – in the range of 10’C to 14’C.

Sunday has a bit of uncertainty – becoming much warmer, but also a weak weather front will bring some cloud and perhaps a bit of light rain at some unknown point. Hazy sunshine otherwise and temperatures in the range of 21’C to 24’C – not bad for the first day of October! Likely fairly cloudy overnight – a small chance of some showers, and around 13’C.

Monday looks warm, though with a chance of heavy showers – that part is quite uncertain.

Fresher for Tuesday.

High pressure is then likely to build over the UK for Wednesday, for at least a couple of days – quite warm by day but likely chilly nights too. Perhaps it might even become warmer for the weekend, some more 20’C days are certainly very possible – I still expect a warmer and drier October than normal.

Not sure when the next forecast will be – I’m out of my usual pattern thanks to Gatwick’s air traffic control deciding that I needed an extra night in Spain. Maybe Saturday/Sunday if I can find time!…

Friday 22nd September 2023

Hello from sunny again Spain, to sunnier soon Britain.

Thanks to Tracy for the photograph.

Early cloud will clear to leave sunny spells for the morning. Cloud will bubble up from around midday with a scattering of showers developing, some heavy – around a 75% chance of catching a couple, but you may miss them all. Reaching around 17’C. Fairly clear skies overnight, down to around 8’C.

By Saturday we see a ridge of high pressure building from the south – with the remnants of Hurricane Nigel merging with low pressure to our west.

It leaves us with a fine day, sunny spells and variable amounts of fair weather cloud. Around 17’C, maybe squeezing an 18’C. Cloud thickening somewhat overnight as weather fronts try to push in from the west – down to around 12’C.

Sunday sees spells of hazy sunshine – the cloud perhaps thick enough for a splash of rain but most likely the rain will stay further west/north. Sunshine amounts likely to increase later in the day. Warmer though quite windy, 19’C, maybe 20’C. The weather front crosses overnight, bringing mostly cloud and the odd spot of rain. No lower than around 15’C.

Monday may start cloud from the overnight weather front but it will clear to leave good spells of sunshine, a bit of fair weather cloud and it will be warm – around 22’C. Reasonably clear skies overnight, though there is a chance of importing a heavy shower from France. Down to around 13’C.

Tuesday is where things start to break down in terms of confidence, but broadly warm, with variable amounts of cloud, some sunshine at times but also a chance of some heavy showers. Around 21’C, give or take.

By Wednesday things are very much up in the air. Likely still on the warm side, but otherwise uncertain – potentially wet or very wet though.

It does look like the jetstream will be re-invigorated as next week goes on, but the track is a little uncertain – generally from Wednesday onwards it should remain quite warm, or warm, but on some days there will be wind and rain – other days fine and pleasant. Getting the day-to-day pattern looks a little off, maybe will take a couple more days of model runs to sort this out.

October still broadly looks warmer and drier than normal, due to an expected high pressure block close to our west – though this certainly does not preclude spells of rain too, depending on where low pressure gets stuck due to the block.

I’m off to go find a castle and then some sangria. Enjoy your weekend!…

Tuesday 19th September 2023

Hola from sunny…cloudy Spain. A day of cloud and showers for me, a week of rain, showers and wind for you.

Thanks to Sue for the photograph.

So the general picture sees the Atlantic in control, though still a warm source of air.

Today will be mostly cloudy with bits and pieces of rain at times. Some occasional brightness, especially later in the day when it should be dry most of the time. Windy, and around 18’C. A fairly cloudy and warm night, windy too, no lower than 16’C with the odd bit of showery light-ish rain around.

Wednesday starts fairly cloudy, a few bright spells possible, the odd shower too. A band of heavy rain will arrive around 11am, give or take, and bring at least 5-6 hours of mostly heavy rain, perhaps very heavy, some notably strong gusts of wind too. 19’C before the rain arrives, 16’C during – and a bit humid. Further pulses of heavy rain may spread up from the south/south-west into the evening – though eventually it will clear east. Skies will clear, winds become light and temperatures drop to around 9’C.

Low pressure still close by for Thursday but we start with sunny spells – perhaps hazy at first with any hangover from the night before’s rain. Heavy showers will developing during the morning, you may miss them but more likely you get a few, perhaps with hail and/or thunder mixed in, some very heavy downpours possible too. Around 17’C and feeling fresher. Variable cloud overnight, some showers possible, down to around 10’C.

Friday starts with sunny spells, but cloud will bubble up with showers breaking out. More likely you get at least a couple of showers – some heavy, but perhaps you miss them. Around 16’C and breezy. Mostly clear skies overnight and chilly, down to around 7’C.

Saturday is a reasonable day as high pressure starts to build once more. Sunny spells for the morning, more in the way of cloud for the afternoon but pleasant enough. Around 16’C. Cloudier overnight, perhaps a bit of showery rain, around 12’C.

By Sunday, we see an ex-hurricane merging with low pressure to our west, helping to drive warmer air once more our way.

Some uncertainty on conditions for Sunday – it will depend on where the weather front is. At worst, cloudy with bits of showery rain, at best hazy sunshine – either way, warm and a bit humid – between 18’C and 22’C depending on sunshine amounts.

Next week starts warm/very warm – probably sunny, though I wouldn’t rule out a weather front being in the mix at some point.…

Friday 15th September 2023

The warmth returns, but low pressure develops too.

Thanks to Tara for the photograph.

This morning sees long spells of sunshine. Some fair-weather cloud will bubble up from around lunchtime, but there will still be some sunny spells – and increasingly so later on. Very warm, 24’C, maybe 25’C. Clear spells for the first half of the night, more cloud later, down to around 12’C.

So for Saturday the general picture is one of low pressure developing, centred to the west of Portugal, which makes for a tricky forecast – low pressure will be edging towards Iceland from North America too, which will be for us next week.

Saturday most likely sees sunny spells, albeit likely hazy sunshine. A small chance of a heavy shower in the afternoon but unlikely as it stands. Very warm, temperatures around 25’C, maybe 26’C. A fairly cloudy and fairly warm night, minimum temperatures around 16’C – some thundery showers will attempt to push north, though how far they get is uncertain – so maybe around a 25% chance of some thunder/rain.

Sunday looks like seeing a band of thundery rain spread north – you may just get a bit of patchy rain, you may get a proper thundery downpour – quite uncertain on details and it will be until the morning. Likely followed by hazy sunshine, and it will be warm and humid, around 22’C. Further thundery downpours possible in the evening and overnight – though hit and miss, you may get nothing or just a bit of rain, you may instead get a couple of notable downpours/thunderstorms. Fairly warm, down to around 16’C.

By Monday the low pressure near Iceland is heading our way, and will scoop up the remnants of the Portuguese thundery low.

A somewhat complicated picture, but broadly speaking sunny spells and showers – though showers likely to come in organised bands, probably heavy at times. Quite windy, perhaps notably gusty in heaviest showers, and temperatures around 20’C. Clear spells overnight though a stray shower possible, around 10’C.

By Tuesday we are in a westerly flow – the Atlantic back in gear. Uncertainty on the track of low pressure systems at this stage, but either sunshine and showers, or cloudy with rain. Quite windy and around 17’C.

Wednesday again sees showers or rain – though a bit warmer, closer to 20’C.

Thursday…showers or rain.

You get the theme, and I need to start work! The Atlantic very much taking over for our first proper autumnal spell with rain or showers most days, and generally quite windy, perhaps strong winds at times.

Good timing for one to go on holiday to Spain! Forecasts should still happen from myself, as long as the wi-fi is decent enough. Enjoy the warm sunshine this weekend whilst you can (if you can).…

Tuesday 12th September 2023

More warmth and sunshine to come, but some cloud and showers in the mix too.

Thanks to Tracy for the photograph.

Today starts fairly cloudy, the odd scattered shower around – and a bit of brightness. Perhaps more in the way of sunny spells this afternoon, but still plenty of cloud, and now a scattering of heavy showers, thunder possible. Warm and humid, reaching around 22’C, maybe 23’C. Showers fading in the evening, then an area of cloud slowly sinks south, perhaps a spot of light rain at times, temperatures around 14’C.

Wednesday starts cloudy. Gradually the sun will break through, and it will become mostly sunny by around lunchtime, give or take. Fair-weather cloud bubbling up during the afternoon, with a small chance of a shower but most places dry. Fresher, 20’C. Some cloud, some clear spells overnight, down to around 12’C.

There’s not a lot happening in the general North Atlantic/Europe area in terms of forcing on our weather – though weather fronts will try to push down from the north-west on Thursday, unsuccessfully.

Generally Thursday sees hazy sunshine, quite a lot of high cloud and fair-weather cloud, but it will be warm, if not very warm and a tad humid once more. Around 23’C, maybe 24’C. The weather front to our north heads further north overnight, we’ll remain with high cloud and temperatures down to around 13’C – a chance of mist/fog/low cloud by dawn.

Friday sees any early mist/fog/low cloud clear fairly quickly, leaving good spells of sunshine, albeit somewhat hazy at times. Most likely quite hot once more, say in the range of 25’C to 27’C – however it does depend on how close the weather front is, and hence how much high cloud there is – certainly plausible that we are closer to the 22’C to 24’C range. A fairly warm night – a chance of some heavy showers breaking out.

And then time for some fun and games.

What looks likely to happen is an elongated area of low pressure develops, stretching from Portugal, through France, and into the UK – tapping into the warmth and humidity.

This leaves conditions highly uncertain for the weekend, but the more likely outcome is for it to be quite hot, with thundery downpours – some sunny spells at times. More likely temperatures broadly in the range of 25’C to 29’C and notably humid. A lower chance that instead we are stuck under general cloud and rain, with temperatures somewhere in the range of 16’C to 22’C. A warm night likely, say around 18’C, with further heavy, showery rain very possible.

Sunday most likely is in the same vein – very warm, humid, some sunny spells possible but more likely some heavy, thundery downpours – perhaps torrential, a small chance of large hail and frequent lightning.

It should be fresher by Monday – and next week most likely reverts to a westerly theme, with wind, rain and showers. But likely warmer than normal!

Perhaps warmer and drier towards the end of September once more. Unusually warmer? We’ll see. I wonder if we’ll end up recording the warmest ever September – in the same year that we recorded the warmest ever June.…

Sunday 10th September 2023 – Thunderstorm Potential

Whilst the main focus for heavy, thundery showers will be to our west, and then later to our north, there is a chance that some may break out further east later this morning, between roughly 10am and 2pm, say around a 30% chance of catching one.

Should it occur, then frequent lightning, torrential downpours and strong gusts of wind are all possible too.

Otherwise it will be another hot and sunny day, albeit with high/mid-level cloud making it hazy at times. Reaching around 29’C if we do get a storm, 31’C without.

Worth keeping an eye on the radar if you have outdoor plans – https://www.netweather.tv/live-weather/radar

No other changes to mention – next full forecast will be on Tuesday morning most likely.…

Friday 8th September 2023

A few more hot days but gradually we’ll return to normal next week.

Thanks to Becky for the photograph.

So the general picture is pretty much the perfect set-up for heat – high pressure over the UK and to our east, low pressure to the west, with a southerly flow. For heat-lovers, it doesn’t get much better.

Friday sees more in the way of high cloud which will make the sun hazy for spells during the day, but it will remain very pleasant and hot – around 30’C. Also more humid than it has been – thanks to that high cloud. Mostly clear skies overnight, another warm night, minimum of 18’C.

Saturday sees long spells of hot sunshine – possibly the hottest day of the spell (and the year), at around 31’C, maybe 32’C. A little bit of fair weather cloud bubbling up in the afternoon and an exceptionally small chance of a thundery downpour – if any form they should be north Midlands ish. Clear spells at first overnight, though tending to become somewhat more cloudy – a very small chance of importing a thundery downpour. Warm and humid, minimum temperatures around 20’C – yuck!

Some uncertainty for Sunday but it remains hot and humid. The more likely outcome sees a mostly sunny day, with some high/mid-level cloud at times, and temperatures reaching somewhere in the range of 30’C to 33’C – an outside chance of a little higher, and even the UK September record of 35.6’C being broken somewhere, say London to Cambridge kind of area. However, there is also some uncertainty around some areas of cloud and thundery showers developing – showers not especially likely down here, but perhaps enough cloud to limit temperatures to 28’C. Another warm night and increasingly cloudy, temperatures no lower than 18’C.

Monday sees the less hot air start to arrive. More in the way of cloud than there has been, but some sunny spells and temperatures still quite hot – somewhere in the range of 25’C to 28’C. A 30% chance of a heavy shower or two during the afternoon – quite uncertain though. Another fairly warm night, otherwise conditions uncertain.

Details uncertain for Tuesday, but broadly the more likely outcome sees a fairly weak weather front bring cloud and some patchy rain – timing uncertain, temperatures also uncertain – somewhere in the range of 20’C to 24’C, depending on timing of the rain band. A much fresher, cooler night likely.

Wednesday more likely sees sunny spells and temperatures around 20’C – still warm.

Thursday, lower confidence but sunny spells, some cloud and a chance of a shower – around 21’C or so.

By this point we will have two notable hurricanes far to our west, Lee and Martha, so higher than normal uncertainty on the patterns downstream in the UK.

Certainly plausible that we go back to very warm for next weekend though with an increased chance of heavy/very heavy showers – arguably the slightly more likely outcome, but all usual (or unusual!) September conditions are plausible too.

There are signals for an unsettled week the week after, but with two hurricanes on the go to our west…who knows.

Enjoy the heat this weekend if you can…relief isn’t far away if you cannot.…

Tuesday 5th September 2023

Heatwave. Quite an exceptional spell of weather for September.

Thanks to Cathy for the photograph.

So the general set-up sees high pressure over the UK, low pressure to the west of Spain/Portugal – and this allows a continental flow, with air originally sourced from Africa. Hence…heatwave.

Today will be hot and sunny – no cloud after any early mist/fog/low cloud patches clear. 29’C, maybe 30’C, though a little bit of a breeze developing. Mostly clear skies overnight though a little high cloud for a time, and one or to patches of mist/fog/low cloud by dawn. A fairly warm night, no lower than 16’C.

Wednesday will be hot and sunny – any early mist/fog/low cloud patches clear. A bit more high cloud around than on Tuesday, but hotter, 31’C, maybe 32’C. Generally more high cloud overnight and temperatures therefore higher, so a warm night at no lower than 18’C – perhaps no lower than 20’C in some spots. Again a chance of some mist/low cloud patches by dawn.

Thursday starts with mist/fog/low cloud in places, but this will clear fairly quickly, and otherwise it will therefore be another day of glorious sunshine – perhaps some high cloud. Again 31’C, maybe 32’C should be achieved. Some high cloud overnight and again some patches of mist/fog/low cloud by dawn, probably more extensive than previous dawns. Some uncertainty over temperatures but broadly another warm night, down to somewhere between 15’C and 19’C.

Friday sees any early mist/fog/low cloud clear fairly quickly, then long spells of sunshine, albeit some high cloud making it hazy at times. Hot, reaching 30’C, maybe 31’C. Clear skies for much of the night, though mist/fog/low cloud developing towards dawn for many places. A warm night, minimums between 18’C and 20’C.

It remains hot into the weekend, with high pressure still in place.

Saturday sees early mist/fog/low cloud patches clear to leave long spells of sunshine. A little bit of cloud bubbling up and an exceptionally small chance of a shower. Likely a shade hotter again, around 32’C. A small chance of a thundery shower overnight, otherwise clear skies and warm, minimum temperatures somewhere between 18’C and 20’C.

Sunday will be another day of long, hot sunshine. A bit of cloud bubbling up and a very small chance of a thundery shower. Around 32’C, maybe a shade more. Another warm night, minimum temperatures somewhere between 17’C and 19’C.

Monday likely remains on the hot and sunny side, though an increasing chance of some showers, perhaps thundery and we should start to ease on the temperatures – somewhere between 25’C and 28’C, depending on sunshine amounts.

Then for the rest of next week we are looking at a gradual normalisation. Not impossible that the hot spell continues a bit longer, but most likely by Tuesday we are down to it being very warm, with more comfortable nights too. And the weather should be more changeable – some sunshine, some cloud, some showers.

Enjoy the hot sunshine, if you can! I fully intend to, after our grumpy July/August.…

Autumn Weather Forecast 2023

Welcome to my autumn weather forecast for 2023.

First thing to note, as always, is that seasonal forecasting remains experimental. Whilst my forecast for June was good, and for August was respectable – for July I predicted a hot month. Aha. Though at least I thought there would be some rain, albeit of a thundery variety rather than Atlantic systems.

So, some of this forecast will be wrong – due to events, it is impossible to give accurate long-range forecasts, but you can give a general guide based on current weather patterns, background signals, etc.

I’m not sure what went wrong in July – did I misread the models? Perhaps but so did every other forecaster who I take notice of, in that case. I know there were unusual plunges of cold air into North America late June, which fired up the jetstream – and then there was some really anomalously warm waters off the coast of North America, which likely gave low pressure systems their oomph this summer.

That’s my working theory on what went wrong anyway.

So whatever I say here, take with a huge pinch of salt.

Thanks to Sarah for the superb photograph, and to all those that sent in – there were a few particularly excellent ones to choose from.

Background Signals

El Niño is still developing and is probably going to be a strong event. I’m not sure that it has too much effect on the UK weather patterns in autumn, perhaps a slightly increased chance of westerly flows later on.

Sea surface temperatures are still warmer than normal around the UK, which increase the chance of warmer than normal temperatures over the UK.

The Quasi-Biennial Oscillation is now in easterly mode – I’ve seen some people on weather forums blame that for our summer weather, but I’m not buying it. Though perhaps it can increase the chance of blocking highs or easterly flows during autumn.

As always, hurricanes/tropical storms and their remnants can affect our weather and add extra uncertainty, especially in September.

September

Speaking of hurricanes, Franklin is the major cause of our hot start to September, pushing high pressure east and allowing us to tap into continental warmth/heat.

So an increasingly hot and sunny start to September, very possible that the highest temperature of the year is recording during September, though I think we’ll stay short of the UK all-time September maximum – which is 35.6’C. Some warm nights too, though some early morning mist/fog/low cloud in places.

Towards the middle third, there will be (small) chances of thundery showers before the heat gradually faces, and by around mid-month or just after, we should be in something more changeable – perhaps briefly unsettled.

In the latter part of the month, probably some variation with some showers, but a return to warm and dry looks more likely overall. Bear in mind that hurricanes/tropical storms far to our west add uncertainty to this.

Overall I expect well above-average temperatures, above-average sunshine, and below-average rainfall – unless you catch a particularly heavy downpour during mid-month.

Confidence level of 85%.

October

Signals are weaker for October though there is a fairly notable signal for high pressure close to the east of the UK.

A dry start may give way to a spell of more unsettled weather into the first half of October, perhaps some very heavy, showery rain at times, and quite windy. Likely mild and occasionally warm.

In the latter half of October, it seems more likely that the high to our east will push west somewhat, meaning rain stays to our west most of the time, and it should generally be dry, mild with some overnight mist/fog.

Overall I expect above-average temperatures, around average sunshine and around or slightly below-average rainfall.

Confidence level of 60%. The main risk is that the high pressure block is further east and low pressure systems get stuck over the UK – bringing a wetter month than I expect.

November

November I think will more likely start dry with high pressure close by. Overnight frosts with some morning mist/fog patches possible. Some sunny days, some cloudy days, temperatures around normal for the time of year.

During the latter part of November, the jetstream should pick up and we’ll have a more westerly flow – some rain at times from weather fronts though I suspect the bulk of the heavy rain and strong winds will be towards Scotland. Generally mild/very mild under such a set-up. Uncertain on cloud/sunshine amounts.

Overall I expect slightly above-average temperatures, around average sunshine, below-average rainfall.

Confidence level of 50%.

Overall and Early Winter Thoughts:

So drier and warmer than normal for autumn, is what I expect. We shall see!

Early thoughts for winter are mostly for a mild and dry winter with a strong signal for higher than normal pressure over Europe.

I wouldn’t preclude a cold spell, and there will be some rain at some point, but overall drier and milder than normal seems the most likely outcome – albeit it’s 3 months away!…

Friday 1st September 2023

It’s the first day of autumn so of course it is time to talk about hot sunshine, at least partly thanks to Hurricane Franklin.

Thanks to Kathryn for the photograph.

Today starts cloudy with scattered heavy showers – an overhang of yesterday’s weather fronts. Gradually the cloud will break to allow for sunny spells, though also there will be a scattering of heavy showers breaking out once more. A tendency for the sun to be hazier later in the day too. Warm, we might squeeze 23’C. High cloud at first overnight, more in the way of low cloud and some mist/fog patches towards dawn. Down to around 14’C.

By Saturday we start to see the Azores High stretch up over the UK – helped along by Hurricane Franklin further to the west.

It will start cloudy, mist/fog patches in some places. Gradually it will burn away from around mid/late morning to leave sunny spells and fair-weather cloud for the rest of the day. A small chance of a shower. Warm, 23’C, maybe 24’C. Fairly clear skies for much of the night, though some low cloud and mist/fog patches developing by dawn. Down to around 11’C.

Sunday again starts with low cloud, mist/fog patches for most areas, but it will quickly lift into long sunny spells, with just a scattering of clouds and a bit of high cloud. Very warm, 25’C, maybe 26’C. Fairly clear skies overnight, some patches of low cloud/mist/fog forming by dawn, down to around 12’C.

By Monday our air source becomes France/Spain, so temperatures tick up. Early low cloud/mist/fog patches will quickly clear to long spells of sunshine. Quite hot, 27’C, maybe a shade more. Mostly clear skies overnight, down to around 13’C.

Tuesday sees long spells of sunshine, with a little high cloud at most. Fairly hot, around 27’C or so. Mostly clear skies for most of the night, but a chance of some patches of low cloud/mist/fog by dawn. Down to around 14’C.

By Wednesday we have pretty much the perfect set-up for heat – low pressure to the west of Spain/Portugal, high pressure to the east, a southerly breeze. Of course, it is September, the sun is weaker, the day is shorter – so the potential isn’t there for anything too hot. And our wet last two months have an impact too from the soil moisture profile and cooler seas around us.

So more sunshine for Wednesday, though perhaps a bit hazier than it has been with more in the way of high/mid-level cloud. Temperatures somewhere in the range of 27’C to 30’C. A warmer night probable, due to the high/mid-level cloud, say around 17’C.

Thursday probably keeps the hot conditions, with high/mid-level cloud making it hazy. Temperatures more likely in the range of 28’C to 32’C. An outside chance of a shower. A warm night probable.

Confidence reduces by Friday, as is fairly usual a week away, but the more likely outcome keeps the hot sunny weather, with temperatures in the range of 27’C to 31’C.

So at some point I’d expect an attempt at a breakdown, whether that be a westerly flow, or thundery showers moving up from the south/south-west, maybe Friday, maybe over the weekend or maybe not until early next week. I’d possibly pin Sunday as the more likely day in a fairly broad range.

Until the breakdown, it will be hot with sunny spells, perhaps hazy. After the breakdown there’s still a fair chance that it will settle down again and remain warm with sunshine at times. But, hurricanes in the western Atlantic can change plans…so always take September mid-range forecasts with even more of a pinch of salt than usual.

Enjoy your weekend, I’ll try to do the autumn forecast during it.…