Monday 14th June 2021

Two more hot days – then the thundery breakdown.

The forecast is going to be a bit vague for later in the week as these style of thundery breakdowns are not only uncertain right up to the moment in terms of where will get thunderstorms and where will get downpours – but are also uncertain in terms of what happens in the 2-3 days after.

Thanks to Fay for the glorious photograph.

Tonight will be mostly cloudy due to a very weak weather front that is spreading south-east slowly – remaining rather warm and humid, eventually down to 16’C.

Tuesday will be rather cloudy in the morning, though some sunny breaks too. Gradually sunshine amounts will increase – with long spells of sunshine by late afternoon, if not earlier. Still very warm, though a bit lower than today, 25’C. Mostly clear skies overnight, fairly warm and quite humid too, 15’C.

Wednesday is the last hot and sunny day of this spell. Long spells of hot sunshine all day, maybe some cloud later in the afternoon as the fun and games approaches. 28’C likely, perhaps more – and humid too. Late evening onwards will see showers spread up from the south – likely heavy or even torrential, thunder/lightning possible. A warm and muggy night, no lower than 18’C.

I stress again the uncertainty for this period!

Thursday morning may well still see further showers or general rain, likely heavy, thunder possible – when it clears is uncertain, it may have cleared by dawn or it may not clear until midday. Likely mostly cloudy afterwards, some bright spells possible – especially if the overnight showers/storms cleared quite early. Likely also still warm and humid, say around 22’C. Mostly cloudy overnight, still quite a warm and humid feel, down to around 15’C – a chance of showers by dawn.

Friday sees low pressure close to our south-east.

It isn’t certain, but most likely further showers or general rain spread up from the south-east. Lots of uncertainty – it could arrive anywhere from morning until evening, it could just be some showers, or it could be many hours of very heavy rain. Maximum temperatures anywhere between 15’C and 22’C. Showers/rain likely continuing into the evening and perhaps overnight for a time too.

Tentatively Saturday looks reasonable, with quite a bit of cloud but some sunny spells, and temperatures around 21’C. I state this with fairly low confidence though.

Either Saturday night or Sunday may see the next spell of heavy, possibly thundery showers moving up from the south – probably still warm or very warm.

Low confidence for next week, but suggestions that it will be cooler than normal and certainly of late, sunshine and showers.…

Saturday 12th June 2021

Becoming hot but a change is in sight for next week…and maybe some thunderstorms.

I had 4 excellent photographs to choose from this week – thanks to Paul for the photograph of the cricket. A sports-themed photograph seems apt given the kick-off of Euro 2020 – alas, Euro 2020 is also to blame for me forgetting to do the forecast last night. Oops.

Saturday will be sunnier than recent days – though still some cloud around. High cloud at first, making the sun a tad hazy, this will clear but fair weather cloud will bubble up at times from late morning – likely late morning through to early afternoon the cloudiest time, but there will be sunny spells too. Very warm but feeling a tad fresher in a light northerly breeze, 24’C. Mostly clear tonight, 12’C.

High pressure remains in control for Sunday, and the positioning just allows something hotter to drift up from the south.

Long spells of sunshine, a little bit of fair weather cloud in the afternoon, hot – reaching 27’C, maybe 28’C. Perfect for sitting indoors and watching football. Mostly clear overnight, down to around 15’C.

Monday morning looks sunny and hot. A very weak weather front spreading down from the north-west in the afternoon will bring more cloud, but still some sunny breaks. Hot, around 27’C, maybe 28’C – a bit humid too. Cloud at times overnight, 14’C.

Tuesday looks like there will be more cloud around, particularly in the morning. Uncertain on how much cloud, and likely some sunny spells also – and generally increasing amounts of sunshine as the day goes on. Temperatures a tad lower but still very warm, around 25’C. Mostly clear skies overnight, down to around 14’C.

Wednesday heralds the change, but could be our hottest day of the year so far. Sunny spells probable in the morning, but cloud bubbling up in the afternoon with a chance of thunderstorms – I know it will be one of those nightmare forecasting situations. Likely hot, say 28’C to 30’C – though there is a chance that the thundery low develops in the morning instead which would reduce potential temperatures. The chance of thunderstorms and torrential downpours will remain in the evening and overnight – I can only offer “a chance” at the moment as it will be difficult to pin down the track and development of thunderstorms until nearer the time. Likely warm and humid overnight too.

Thursday…well…it could be anything depending on how and where the thundery low develops on Wednesday. It could be sunny, it could be cloudy, there could still be thunderstorms or general rain around. It might be fresher – or it might still be very warm and humid.

I guess I should give up here. Until the thundery low is resolved in the models, late next week and next weekend could be anything you might expect in June.

I’d suggest two main broad patterns are more likely, one is a return to fresher, more westerly-based weather once Wednesday’s thundery low clears – sunny spells, a chance of a shower or two, and temperatures around 20’C, give or take a couple of degrees.

But the thundery low could instead linger close to the UK for a few days (or a secondary thundery low may follow from the south), bringing further thunderstorms/showers/general heavy rain – but also some further very warm/hot sunshine at times, plus humidity.

Either way, the very warm/quite hot, fine and sunny conditions of late are likely to re-assert themselves afterwards. Summer will take a break, but it will be coming home quickly.

I’ll be back on Monday. Enjoy the football/beers/BBQ/sunbathing/picnic – whatever it is you have planned.…

Monday 7th June 2021

Summer continues. Not perfectly glorious – some cloud at times – but also temperatures ticking up to quite hot.

Thanks to Tracy for the photograph.

Some patchy cloud at first tonight but becoming generally clear as the night goes on, down to around 11’C.

Tuesday continues with the theme of the Azores High stretching towards and over the UK – it isn’t especially strong but there is nothing going on in the Atlantic either with a weak jetstream to our north, so settled conditions prevail.

There will be good spells of very warm sunshine. Some bits of cloud floating around at times, probably some high cloud in the afternoon making it a tad hazy, but generally very pleasant – 24’C, maybe 25’C. Clear skies overnight, down to around 11’C.

Wednesday will see long spells of sunshine. A bit of fair weather cloud later in the afternoon drifting in from the west – but otherwise mostly sunny. Quite hot, 26’C. Mostly clear skies overnight and a little stuffy too, 15’C.

Thursday looks cloudier as remnants of decaying weather fronts from the Atlantic get mixed in. Quite how much cloud is uncertain, but likely more cloud than sunshine overall – but still very warm with some sunshine – and a trend towards more sunshine later in the afternoon. Around 25’C, give or take a degree or two, depending on how much sunshine we end up with. Mostly clear skies overnight, down to around 13’C.

Likely quite a bit of cloud around in the morning on Friday, though very warm with some sunny breaks also. Generally becoming sunnier in the afternoon. Temperatures again will depend on quite how much cloud there is, but somewhere between 24’C and 27’C. Mostly clear overnight, down to around 13’C.

Saturday sees the high pressure become more UK-focused.

Either good spells of sunshine with some fair weather cloud, or long spells of sunshine – temperatures in the hot range, reaching somewhere between 26’C and 28’C.

Sunday looks very similar to Saturday – with the added intrigue that the 13th June is the only date in June never to have reached 30’C in the UK – there is an outside chance that somewhere might.

How long can this go on for?

Well, I’m pretty confident that it will stay hot and sunny for Monday. Less confident for Tuesday, but more likely than not.

But at some point next week, either midweek or at best late in the week, I’d expect a transition to a short unsettled spell, perhaps initiated by a thundery breakdown. At the moment, I expect it to be a brief unsettled spell with fine and warm conditions re-asserting themselves afterwards – but this is a long way away.

Best get the BBQ/picnic planned.…

Summer Weather Forecast 2021

Welcome to my Summer Weather Forecast for 2021.

I think if this forecast is more right than wrong, most of you should be pleased. Of course, I don’t always get it right – seasonal forecasts are experimental – at best some of the details will be wrong, at worst a month or so could be completely opposite to what I expect – competing drivers of the weather over the UK do make long-term predictions difficult.

This happened to my spring forecast – I got March and April reasonably close (though didn’t expect the amount of cold nights we had), but May I forecasted warm and sunny for most of it. Well it was for the last 5 days – does that count?! Of course not – my spring forecast was a disaster for May, though I did also suggest that that June would be sunnier and warmer than average – so far so good on that count.

So don’t take it as gospel.

Also I do ask if you can share the forecast in some way. Invite friends on Facebook, retweet on Twitter, e-mail it to your boss. Whatever works.

And a final piece of admin is to say thank you to Kira for the photograph adorning the forecast and the cover of the Facebook page for the next 3 months. A donation has been sent to Breast Cancer Now.

Background signals

Background signals generally have less influence in summer over UK weather.

La Niña has faded and we are broadly in neutral conditions, though perhaps there might be some “atmospheric memory” which could increase the chances of cloudier, cooler conditions from the north-west at times – similar to last July, but any spells should be short.

The sudden stratospheric warming event in January led to blocking highs which brought us cold weather in January, February and, arguably, April. It is my view that this pattern can persist in summer – though at this time of year, blocking highs nearly will mean warmer (unless over Greenland) and sunnier than normal conditions. I don’t think this is accepted scientific fact though – more my belief.

Sea surface temperatures around the UK are lower than normal, which would suggest that until they warm up, land temperatures will tend to be a shade lower than otherwise would be expected – though I doubt you’ll notice it.

June

June started very warm and sunny, and I expect this to continue into the second week, though with scattered heavy showers on a few days too, perhaps with thunder.

High pressure should remain in control for much of the month, generally close to Scandinavia – suggestions of a short hot spell around mid-month, with a breakdown to a short cooler and unsettled spell are there – before high pressure reasserts itself with more warm/very warm and fairly sunny weather. Away from the short hot spell/breakdown, low cloud may form overnight on some nights, and take a bit of time to clear in the morning.

Suggestions of something more changeable towards the very end of the month.

Overall I expect June to be sunnier than average, warmer than average with rainfall totals below average – unless one of the thundery showers is especially potent.

Confidence around 90%.

July

July looks a bit more mixed, and may start cooler than normal, with some rain/showers – but also some fine, sunny days in the mix.

Signals are fairly weak after the beginning 7-10 days, but high pressure should feature over or close to the UK. Whilst some changeable conditions will be likely – I’m not expecting a long-lasting settled spell like in June, I think the main theme should still be for more very warm, sunny weather – hot at times though also some thundery downpours developing on some days.

Overall I expect July to be around average for sunshine, perhaps a tad below, slightly warmer than average and slightly wetter than average.

Confidence around 60%.

August

In recent years we’ve often seen the summer deteriorating by late July and through August, though this year I am more hopeful that high pressure will stage a renaissance.

For much of the month, high pressure should be close to the UK, meaning many more days of warm/very warm sunshine – hot at times, but also a chance of cooler days, depending on the exact positioning of high pressure.

There is a slight signal for it to shift north of the UK at times, so this will again mean some periods where it is still very warm and sunny, but heavy, thundery showers will develop.

I don’t have a particular reading over what part of August will be the hottest, but perhaps the latter half if I’m pushed.

Overall I expect August to be sunnier than normal, warmer than normal (though that does depend on high pressure positioning) and slightly below average for rainfall (though again, catch a notable downpour and locally you may end up above average).

Confidence around 70%.

Summary and Autumn suggestions

Not bad, huh? If it comes true, of course, as I will get some things wrong – signals are particularly weak for July so it could easily end up wetter than I expect, I do feel more confident for August’s forecast than July’s.

Looking ahead to autumn…and winter…yes it is time to start thinking about winter forecasts.

Currently there is a slight signal for a wetter than normal September. There is a fairly strong signal for a cooler than normal second half to autumn – perhaps colder than normal might be more descriptive, but also drier than normal second half.

There are background signals suggesting that cold spells are more likely than normal this coming winter too.

Autumn/winter is, of course, a long way away and things can and will change in terms of background signals, so only take this as a guide for now.

Enjoy the summer.…

Thursday 2rd June 2021

Staying very warm, often sunny – but there are some showers in the mix too.

Thanks to Victoria for the photograph.

Tonight sees quite a lot of mid-level cloud, perhaps even a spot of light rain this evening. Down to around 14’C – a small chance of importing the left-overs of continental thundery showers by dawn.

Friday has a bit of uncertainty – thunderstorms over the continent will extend their reach to the eastern parts of England as they drift north, and there is always some uncertainty on their track. Most likely we’ll end up with quite a lot of medium level cloud, some occasional sunny breaks and possibly some occasional light/moderate showery rain – but it will depend on how far west it stretches.

So we could end up sunnier than this, or we could end up generally cloudier and wetter, perhaps with a rumble of thunder. Temperatures will depend on sunshine amounts, and hence quite how far west the rain reaches, so maximum temperatures anywhere between 15’C and 21’C – quite humid too. Cloud mostly clearing overnight, down to around 11’C.

For Saturday we are back to warm sunshine. There will be some cloud bubbling up in the afternoon, but broadly warm and sunny – around 22’C. Fairly clear skies overnight, down to around 11’C.

By Sunday the picture remains that high pressure is in control, though not the strongest ever build.

Plenty of sunshine again, but fair weather cloud will bubble up – likely more than on Saturday with a 15% chance of catching a heavy shower in the afternoon. Warm. around 22’C. Variable cloud overnight, down to around 13’C.

Monday again sees sunny spells, but quite a bit of cloud will bubble up. A greater chance of heavy showers developing, and I’d estimate around a 30% chance of catching one or two – perhaps very heavy with a small chance of thunder too. Very warm, 23’C, perhaps a shade more. Variable amounts of cloud overnight, down to around 13’C.

Similar again for Tuesday, sunny spells, some cloud bubbling up and around a 25% chance of catching a heavy shower – a small chance of thunder. Very warm, around 23’C or so. Variable cloud overnight, down to around 13’C.

Wednesday, Thursday and Friday should remain very warm with sunny spells. Some cloud bubbling up and a small chance of a heavy shower. Around 24’C, maybe a tad more. Clear spells overnight, down to around 13’C.

Next weekend is quite a way away – most likely it remains mostly settled with sunny spells and a small chance of a shower, though perhaps becoming less warm – that bit more uncertain.

I will get my summer forecast written this weekend!…

Photograph Request – Summer Forecast

So it’s already officially one day into summer and I still haven’t written my summer weather forecast.

But I cannot do a summer weather forecast without a summer photograph.

And for the one I choose, I will donate £15 to the charity of their choice – but please make sure it is not something that people will argue with no matter how decent the cause – ie any organisation involved in politics/religion. Fluffy animals, heart research – that kind of thing. I try to keep this a politics free zone as best as possible.

Requirements

  1. The photograph needs to have longer length than height (ie landscape orientation). This is because it doesn’t work as a cover photograph on Facebook or on my website if it is not.
  2. It must have weather. I try to use one close to representing my forecast – so remember that there is more than one weather type possible in summer.
  3. It must feature the local area.

How to send

Please either e-mail them to me or reply to the Facebook post requesting a photograph. I will not be able to reply to them all but I will look at them all!…