Model Output Discussion - Autumn arrives

[kold weather]

There does seem to be a fairly strong signal for some rainfall even for the SE between Mon-Wed next week as pressure lowers and we develop what looks like a more mobile pattern again.

Before that point though we have the matter of probably a 5-7 day heatwave for some parts of CS/SW England. Models appear to be somewhat trending upwards for Fri-Sun period. ECM developing 34c (which likely translate to about 35-36c when accounting for large sunshine levels and under temp bias in such set-ups) and the GFS throwing out 35-36c as well.

This is still *exceptional* temperatures. Its somewhat less impressive after the monster heat shot in July, but remember that pre July 22 a 36.5c would get you well into the top 10 hottest days EVER, and such a temperature is certainly possible on the upper end of this set-up, as we saw pretty clearly in Aug 2020 which IMO looks fairly similar in many respects.

 

[mushymanrob]

Breakdown? what breakdown?

THIS breakdown.... a shallow low is expected to become dominant for a time over the UK, this is the 8-14 day mean so Aug 15th - 21st.
Waiting in the wings though is the Azores high which id expect to rebuild in towards the UK, and ive posted as much somewhere else a couple of days ago. I said that because @Tamara has just said something similar...

 

[Scorcher]

9 minutes ago, NTC said:

Why are you so aggressive it won't happen, you will not accept that it will  at some point come to an end. Why can't Mark say if he thinks it will end why do you have to be right Scorcher?

A lot of people agree with me as you can see from the response to my post. Of course there will be a breakdown at some point- I've never said otherwise. There is absolutely no certainty over it though- which is the point I've made very clearly. Misleading to suggest otherwise.

My opinion is based on more than just hope and conjecture- check out Mushy's post above.

Edited August 8, 2022 by Scorcher

[seb]

Guys, I don't think anyone is being aggressive and no one should be. We all have our preferred weather but just like there are some in winter who see cold and snow when it isn't showing on the models, there are a few here who for the past few months have seen breakdown after breakdown where models aren't showing one.

I just went back to 23, 24 and 25 June so I won't be unfair but the posters who stand out anecdotally stated that models back then were showing an unsettled and cool pattern throughout the first two weeks of August, including rain in the S & E. The models didn't show that but they actually showed more rain than they are showing now until the end of their runs. For my location we apparently were due 15-30mm by 6 August. We had some drizzle and one 2 minute shower. You couldn't even see it on the hard, parched soil.

Of course sooner or later there will be a pattern change but it is is extremely unlikely to happen next week, just as it didn't two weeks ago or the many times before it was apparently going to turn unsettled.

Whatever causes the current pattern (a pattern that goes back to November last year, some short interruptions - for example Eunice - aside), it seems more or less stuck. Whether it's climate change or something else, I don't know but we it is what it is.

Edited August 8, 2022 by seb

[Singularity]

Important to be specific when talking of a breakdown. What is of? In this case a lengthy heatwave, by sometime Sun-Tue.

The troubling aspect for southern UK water reserves is that modelling generally indicates a traditional wettest north, driest south pattern to follow, as the Azores High remains close enough to keep extending across mainland Europe frequently while southern UK gets involved at times too.

By contrast the north may see quite a lot of rain, increasing the sense that we could do with a monumental emergency water transfer pipeline running from Scotland to England. If only!

[NTC]

Just now, Singularity said:

Important to be specific when talking of a breakdown. What is of? In this case a lengthy heatwave, by sometime Sun-Tue.

The troubling aspect for southern UK water reserves is that modelling generally indicates a traditional wettest north, driest south pattern to follow, as the Azores High remains close enough to keep extending across mainland Europe frequently while southern UK gets involved at times too.

By contrast the north may see quite a lot of rain, increasing the sense that we could do with a monumental emergency water transfer pipeline running from Scotland to England. If only!

Yorkshire Water has a circular pipeline which can move water from any part of the region to a dry area ie Pennines to East coast, if they can have this system why can't we have a national pipeline? Surely it can't be that difficult for Yorkshire's system to connect to Trent and Trent connects to.... etc.

[mushymanrob]

8 minutes ago, Singularity said:

Important to be specific when talking of a breakdown. What is of? In this case a lengthy heatwave, by sometime Sun-Tue.

The troubling aspect for southern UK water reserves is that modelling generally indicates a traditional wettest north, driest south pattern to follow, as the Azores High remains close enough to keep extending across mainland Europe frequently while southern UK gets involved at times too.

By contrast the north may see quite a lot of rain, increasing the sense that we could do with a monumental emergency water transfer pipeline running from Scotland to England. If only!

The Anomaly chart i posed suggests there might be a Southern Thundery element to the "breakdown" though.. like yesterdays 12zECM, never really cooling down far but with thundery showers mainly in the South.

 

[MATTWOLVES 3]

1 hour ago, damianslaw said:

Wish we could bag vitamin D we receive in summer and store for winter..

No doubt Damian that sun is a big vitamin D producer...regarding the Winter keep a diet rich in omega 3 fish..cod liver oil etc...and you will get all the vit D you need.

And it seems what the mods said yesterday regarding bickering over conditions as fallen on deaf ears....How on earth people revert to squabbling over the Weather baffles me! It is what it is and will always remain out of our control...regardless of the conditions we would like to see!

A beautiful day and week ahead...anyone not enjoying this leaves me gobsmacked...Its getting hotter through the week. Beyond this perhaps a little instability and some downpours being triggered,but I emphasise this does not guarantee widespread huge rainfall totals in the areas of concern!

What comes next? Personally I think  a reload after a minor blip...the GFS mean highlights a recovery In pressure beyond day 10. One top keep an eye on...

@Tamaraexplained wonderfully as to how these patterns can be hard to shift and @mushymanrob highlights how the Noaa charts also strengthen the Azores High again.

Wonderfull stuff...everyone keep a cool head and enjoy yourselves....weather is weather and can't be changed...life goes on regardless.

 

 

Edited August 8, 2022 by MATTWOLVES

[SnowBear]

As I see it will take the awakening of the hurricane systems to break this pattern as we have seen many times in years past. 

This year, the seas off Mauritania, the southern Western Sahara coast, Senegal and The Gambia have been 1-2°c lower than normal, at around 24-25°c with a small patch of 26°c off Senegal. Usually they will be at 26°c and above. 26°c is generally the sea surface temperature for tropical storm/hurricane development. 

We do now have a disturbance moving off that coast near Senegal which has a 40% chance of developing into a tropical system, but currently its a disorganised area of convection. 

Once we do start to see systems move off and start their long tracks into the Northern Atlantic then we will start to see our patterns change too. 

Many have spoken on how little energy the Atlantic has at the moment, as there is little energy being introduced by these systems right now, it results in what we see in our weather. 

 

[Liquid]

1 hour ago, seb said:

Guys, I don't think anyone is being aggressive and no one should be. We all have our preferred weather but just like there are some in winter who see cold and snow when it isn't showing on the models, there are a few here who for the past few months have seen breakdown after breakdown where models aren't showing one.

I just went back to 23, 24 and 25 June so I won't be unfair but the posters who stand out anecdotally stated that models back then were showing an unsettled and cool pattern throughout the first two weeks of August, including rain in the S & E. The models didn't show that but they actually showed more rain than they are showing now until the end of their runs. For my location we apparently were due 15-30mm by 6 August. We had some drizzle and one 2 minute shower. You couldn't even see it on the hard, parched soil.

Of course sooner or later there will be a pattern change but it is is extremely unlikely to happen next week, just as it didn't two weeks ago or the many times before it was apparently going to turn unsettled.

Whatever causes the current pattern (a pattern that goes back to November last year, some short interruptions - for example Eunice - aside), it seems more or less stuck. Whether it's climate change or something else, I don't know but we it is what it is.

i think personally it is climate change.  The north atlantic current has slowed, meaning i feel there is less effect of the gulf stream on our shores.  In short in my view this causes more blocked patterns.  Leading to wet/cold/hot/dry periods, without the strength of the atlantic in years past.

Im down in Norwich at the moment, everything is dust. Hard baked clay soil, ive never seen it so dry, aside 1976 when i was born, which i wouldnt remember lol.

Id welcome rain, but lets enjoy the sun a little. Mother nature will pay us back at some point. 

[MattStoke]

MO outlook pretty much reflects what the models are currently showing; Temperatures trending downwards after this week but staying very warm. Some rain in the north and thundery showers in the south. Then turning more settled again.

[Captain Shortwave]

ICON first out;

Hot/Very hot throughout the weekend

  
 

Mid thirties in the south, high twenties or even 30c in the north.

Monday looks humid and increasingly showery.

Still very warm or hot in any sunnier spells. The danger with thunderstorms of course is the risk of flash floods in places that are currently bone dry, the other being the increased risk of lightning being a fire hazard in the same locations.

[mb018538]

I’ve also seen posted elsewhere that the strongly above average SSTs down to our SW may also be partly responsible for the continued above average heights in the mid lats this summer. Everything has been shunted further north than a normal year.

[seb]

32 minutes ago, MattStoke said:

MO outlook pretty much reflects what the models are currently showing; Temperatures trending downwards after this week but staying very warm. Some rain in the north and thundery showers in the south. Then turning more settled again.

Yep. Continued very warm, locally hot away from the NW. Possibly some showers or storms then back to more settled into September.

No breakdown.

GFS 12z rolling out as we speak. Let’s see what we get.

[seb]

1 hour ago, SnowBear said:

As I see it will take the awakening of the hurricane systems to break this pattern as we have seen many times in years past. 

This year, the seas off Mauritania, the southern Western Sahara coast, Senegal and The Gambia have been 1-2°c lower than normal, at around 24-25°c with a small patch of 26°c off Senegal. Usually they will be at 26°c and above. 26°c is generally the sea surface temperature for tropical storm/hurricane development. 

We do now have a disturbance moving off that coast near Senegal which has a 40% chance of developing into a tropical system, but currently its a disorganised area of convection. 

Once we do start to see systems move off and start their long tracks into the Northern Atlantic then we will start to see our patterns change too. 

Many have spoken on how little energy the Atlantic has at the moment, as there is little energy being introduced by these systems right now, it results in what we see in our weather. 

 

I generally agree, however the lack of hurricanes can't explain the weak jet stream since November last year. So something, somewhere is missing or has (temporarily?) changed.

[damianslaw]

2 minutes ago, seb said:

I generally agree, however the lack of hurricanes can't explain the weak jet stream since November last year. So something, somewhere is missing or has (temporarily?) changed.

We've had periods with weak jetstream in the past often coinciding with lengthy dry periods.. a notable one was March 95 to Apr 97, Dec 09 to Apr 12 despite a rather wet summer and second part 2011 brought a very weak jet. Coincidentally the last 2 very dry years occurred in these periods 1996, 2010. 

[damianslaw]

2 hours ago, Liquid said:

i think personally it is climate change.  The north atlantic current has slowed, meaning i feel there is less effect of the gulf stream on our shores.  In short in my view this causes more blocked patterns.  Leading to wet/cold/hot/dry periods, without the strength of the atlantic in years past.

Im down in Norwich at the moment, everything is dust. Hard baked clay soil, ive never seen it so dry, aside 1976 when i was born, which i wouldnt remember lol.

Id welcome rain, but lets enjoy the sun a little. Mother nature will pay us back at some point. 

Yes certainly noticeable we are seeing much less variety on a day to day basis.. I.e classic ridge / trough patterns alternating with one another. Blocked spells seem to last longer and recur.. likewise wet periods lock in for long periods... we have seen some very long wet periods very recently courtesy of wavy buckled jet patterns, I'm talking last 20 years. Mind we've had them centuries ago as well..

Edited August 8, 2022 by damianslaw

[sheikhy]

Very hot ukmo 12z up to 144 hours!probably hotter than gfs for friday and saturday!!

[I remember Atlantic 252]

4 minutes ago, sheikhy said:

Very hot ukmo 12z up to 144 hours!probably hotter than gfs for friday and saturday!!

To me this look cooler? higher dew points maybe, but hopefully 30 degree heat gone

[Man With Beard]

GFS 12Z again maintains heat all the way until Monday.

If somewhere managed to squeeze a 30C today, that could mean 8 consecutive 30C plus days.

UKMO looking a bit more questionable by Sunday.

[sheikhy]

8 minutes ago, I remember Atlantic 252 said:

To me this look cooler? higher dew points maybe, but hopefully 30 degree heat gone

Problem is we dont know how much precipitation there is on that chart!one things for certain it will be very humid with 850s of +14 widely across the uk!gfs stays hot for england till tuesday next week!

[AWD]

I don't normally post in here as it can be a very "argumentive" place at times, but it's usually better in summer than in winter.  

I've watched the last couple of days output and there is definitely a signal for some sort of convective potential around the end of the weekend into next week.  Obviously looking at detail etc is pointless at this range (PPN charts etc at this range aren't worth the time of day), as we all know convective weather is difficult enough to forecast at 24 hours out, let alone a week+ out.

Clearly this week is going to become increasingly hot for England and Wales as it progresses, with near enough clear skies and warm nights.  I'll be venturing down to Bognor Regis with the kids later in the week to enjoy the summer weather myself.  Naturally, aside from temperature maxes, with this week's weather all but certain, a lot of discussion is going to take place around the end of the weekend and into next week where things become much more uncertain.  Both the GFS and UKMO 12z runs lower heights enough to bring instability across the country;

Little in the way of frontal rainfall still, away from Scotland and NI, but nevertheless a change to this week's fully settled conditions.  I won't mention the "breakdown" word as that seems to rile some folk up for some reason, so I'll just call it a change. 

As a convective weather fan, early indications of conditions into next week look interesting.  Remaining warm still, (although not quite as hot as this week), but with scope for some interesting cloudscapes and storms.  How long it will last for?  Who knows, I don't.  Wayyyyy in FI then.

Worth a shout out for our Scottish members, as it's only fair they're not forgotten about this week.  The GFS 12z, for the peak of the heat next weekend, does suggest some quite sharp temperature variations across the country.  The south could get well into the mid thirties whilst parts of Scotland could struggle to get into the mid teens;

Enjoy this week if your fortunate to have time off work, and if your a convective weather fan or just want some rainfall in the SE, then there is a twinkle at the end of the tunnel appearing.  Keep watching over the next few days.  I'll now scurry away back to my hole before I get rounded upon!  

[Captain Shortwave]

The UKMO and GEM probably hang on to sunny spells and the heat on Sunday. The GEM (Which looks similar) has rain pushing into the south west later on Sunday. Monday looks ripe with cold air aloft and very warm air lower down, a long way to go but this clearly presents as the best chance for some decent thunderstorms for quite some time.
The GFS is slower, but with a more easterly element to the winds means that the temperatures are not quite as hot as the previous runs. Monday is still hot though because of these differences.

Edited August 8, 2022 by Captain Shortwave

[clark3r]

The gfs has been quite persistent in keeping the heat until Monday, and mid 30s in the south at the weekend, wonder if the ECM will side with gfs this eve, wonder if ukm will extend the heat tomorrow, or vise verser the ecm follows ukm tonight and gfs follows suit tomorrow. 

[damianslaw]

GFS continues to suggest something more unsettled as we start next week.. until then a week of hot sunshine for many.. those who booked this week off for a holiday in the UK will be very happy.. those who booked next week may end up feeling very short changed! Luck of the draw when it comes to the school holidays period in the UK. The last 2 weeks and start of school holidays in Lake District have been largely quite poor or average at best.