Model discussion highlights

[Tamara]

11 hours ago, TSNWK said:

In my view you can have as many global teleconnections theories  as you like  (they tend to come in fads  until proven wrong )  but the simple fact of the  matter is the chaos and  butterfly effect that increasingly extrapolates its own merry dance the further out we look..  an elephant fart in Thailand could introduce the butterfly effect that along with random chaos of the atmospheres scuppers any teleconnections theory beyond around 3 weeks in my humble opinion. Personally I do find the 500mb charts broadly there for two weeks out with detail following within that framework far more often than not.

My last reiteration on this as I accept that no amount of rationale is going to be worthwhile when disillusion with the weather in the UK overrides any reasoning behind it.

There is no "theory". And there is certainly no "fad". That is, frankly, unwarranted trivialisation.  These atmospheric drivers in the tropics and extra tropics are steeped in empirical science of the atmosphere & the physics of the turning force of the jet stream through angular momentum processes. All put together into a diagnostic framework.

There is nothing wrong with the science,. What can go wrong is natural human error in decoding the complexities from time to time - but that doesn't make the teleconnection tools related to the science themselves wrong or of little use.  As much as it doesn't make the 500mb charts wrong at any given time, irrespective of the fact that they may change in their outlook subsequently according to the diagnostic that drives then and there can equally be human error with these. The point is that they attempt to model the diagnostic processes that are in never ending flux - and such flux constantly evolves the outlook. The 500mb charts are the best overview of numerical overview interpretation. There is no disputing that. However, as stated, these evolve & change as much as NWP evolves & changes its outlook according to its interpretation of the diagnostics that drive them.

The reasoning for the changes this July have been stated umpteen times. it is not the teleconnections that are to blame for departure from expectations (in the UK). And neither is the present situation to do with any butterfly or random effects. It is a natural cyclical ebb in the state of the atmosphere that has produced a pronounced disconnect much greater than was anticipated.  Nothing more, nothing less.

Finally, and with that in mind, ownership has to be taken for the fact that the focus of the downturn happens to be in the vicinity of the focus of a UK weather forum. Better to accept the reality of that disappointment, and own the disappointment - than blame the science, or the tools used based on the science.

Whatever the weather, hope as many of you can enjoy the remainder of the summer.

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4889208

[johnholmes]

my take on the 500 mb anomaly charts

Friday 14th  and no major changes showing, indeed, probably as a result of the trough/ridge development a few days ago off the western seaboard of n America some indication of height rises/ridging around 30W/s Greenland into the trough now e of the uk, little change in contour heights over the uk, all show origin from polar areas.

So no prob of any major warming or much change in the current weather patterns in the next 14 days. That said the 8-14 is a bit different from its last output in the far west. Watch for the next couple of NOAA outputs to see what shows up.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4889155

[MattH]

Morning.

Another week and another cyclonic one at that, the emphasis, as a few have mentioned in recent posts, is for a more cyclonic push just in time for another 'summer weekend' as well, with low pressure returning more significantly by Fri and into the forthcoming weekend as well.

That aside and the medium and long-term processes to, eventually, change the pattern are underway and a close watch is now required on rather than having the primary trough over the UK to see it pull back westwards. At a minimum even if the weather remains more cyclonic, with the trough just to the W, a trend towards a greater risk of S or SW'ly flows, than compared with W or NW'lies should develop. We can see on the OLR plot and the latest AAM data that upstream Pacific changes are now starting to take place as long predicted, but clearly incorrectly in terms of timing.

You do have to admit though that the outlook for the rest of July is looking increasingly poor and the key area where any predictions have gone array for July are, again, linked to timing rather than the overall expected changes. So, therefore, one has to hold your hands up and say that any upstream changes now don't look like saving July, or not in any significant way. There may still be a change for the upper troughed pattern to pull back westwards within the next 10 to 14 days, with a late July 'warm up', but that may still coincide with a more cyclonic pattern. Until that happens as well then temperatures are really going to struggle in what is, on average, the warmest part of the year/summer.

However, as discussed a handful of times the upstream Pacific changes are on the way so a close eye on late July onwards is now certainly required, but even I have been surprised by how 'locked in' the cyclonic pattern this July has become and looks set to continue as well, the reasons for that are open to discussion I guess.

All that aside and yes, after the superb May and June, July 'feels' even worse and clearly a 'polar opposite' regime to what was in place during May and June. However, this is the British Isles after all and even in the best of summers, do we get three months of sunny, warm weather? - the answer is obviously, no, we don't. After the current spell clears through though we still have the whole of Aug left and a few decent weeks of summer weather in Aug, when coupled with what we got in May and June would still, IMO, make this a reasonable summer overall. The upcoming rise in AAM certainly brings significant hope for Aug and could well be a key story for how the rest of the summer plays out...

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4890522

[johnholmes]

My update with the NOAA 500 mb anomaly charts

Sunday 16 July

Written Monday morning

Little change on the 6-10 on Sunday evening from the Saturday output or indeed for several days. A very slight increase in contour heights, very slight changes in the main trough position but still any contours over the UK and northern France still remain with sources in polar regions. Not until over central/southern France is any contour from a region south of these cold areas. The ridging first shown 2-3 days ago in the south Greenland area still there. I believe this is as a result of changes about 3-4 days ago in the far west, (eastern Pacific) as a ridge-trough set up in that area from what had been a rather flabby westerly flow into the far west of n America.The 8-14’s are not that different,

So no major surface weather changes seem likely, keeping the current weather pattern of the past few days.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4890577

[johnholmes]

1 hour ago, danm said:

Wave number 5 pattern across the globe currently, according to the Met. Causing 5 blocks of lower than average pressure and 5 areas of higher than average pressure. We have obv been in one of the lower than average areas. Apparently this pattern is hard to shift:

 

Yes if the distance between each ridge or trough is around 60 degrees it was always looked to be a very slowly evolving pattern; long before the days of computers. This came from many years of collecting these instances, what was called empirical forecasting.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4891374

[johnholmes]

Another update with the 500 mb anomaly charts

Moving on to Wednesday morning 19 July using the charts from last evening=18 July

Precious little change in the UK area, still with contour lines that originate from polar areas for 6-10 and the 8-14, smoothed out as is often the case but no marked changes and contour lines over UK stubbornly originate from cold regions. The 6-10 has a more –ve anomaly showing just off ne England which does not bode well for areas close to it, perhaps, and the westerly flow, turning n of west is stronger right down to southern France n Spain. So an unsettled surface outlook seems likely for the next 2 weeks. Obviously the odd individual day with mostly dry, even rather warm, especially for the SE quarter of the UK but that is about all.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4891669

[Tamara]

7 hours ago, jules216 said:

I wouldnt read in to the teleconections too much. With GSDM you are told not to try and fit them in to your prefered outcome in the winter, I dont see why it should be different in summer. There are other Global pattern that can dictate European circulation, like the persistant subtropical ridges who once they establish are dificult to turn around, remember 2007,2012 or 2015. Those were all lenghty hot periods in south/central Europe, and really long unsettled UK spells. The GSDM probably more useful tool for American continent as it starts to affect them first by the tíme the Rossby Wave is supposed to hit Europe who knows at what angles will the cyclonic/anticyclonic wave breaks happen. I know at certain times like perhaps this May and June you could call the GSDM a success with what happened but there were equal amount of times when it did not lead to prefed outcomes. Another issue is timing and its dangerous to presume certain dates of Large scale changes as I ve seen forecasters ending being laughed at on Twitter when they tried to use GSDM for a specific forecast dates ended being wrong/or few hundred miles out.

A response to this is merited. The GSDM is not an aid to support weather biases & preferences or to try to fit its findings at any given time into a desired outcome. It is a diagnostic model completely devoid of human emotions. Therefore the same applies all year around in respect of neutral objectivity rather than hope-casting preference.

Used properly, but more importantly (and this is the hardest part) used as accurately as possible it will give as useful guidance to any part of the NH (indeed in the SH if one lives in that part of the globe) as it comprises both a tropical & extra tropical gauge of global wind-flow which can assist with trying to anticipate downstream patterns based on evolution of forcing in the tropics which propagates into the extra tropics and influences  jet stream patterns from upstream.

Taking preference out of the occasion, the GSDM appeared to "work" in the later Spring & early Summer b/c it was much easier to read a very emphatic wind-flow signal that favoured downstream amplification. What was much harder to envisage was the lull downturn in the tropics which led to a disconnect much greater than most anticipated. The GSDM still "worked" but various forecasters and lesser mortals like me misread the depth of the new signal and therefore misread the diagnostic and prompted too premature an uptick in momentum..  It is clearly more complex than that, but for purposes of this reply it should suffice

So that discrepancy is not any flaw in the GSDM, It is all part of challenge of using the diagnostic tool to try and anticipate the never ending flux of the atmosphere.  The challenge is the reward, especially when things go wrong and further investigation is required - it should not become the finger of blame & myopic scepticism. Personal frustrations are very much linked to this

Timing, based on intra-seasonal timescales of forcing in the tropics (MJO &CCKW related just for example) also meets challenges - based on the margins of periodicity (timeline recurrence of the phenomenon) - but again that is down to the analyst to evaluate as accurately as possible and not any culpability of the diagnostic product itself.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4891909

[Tamara]

5 hours ago, MATTWOLVES 3 said:

To say the teleconnections are a complete bust is perhaps over the top. Sometimes they will get it wrong and I feel this is becoming more likely due to over riding factors such as Climate change. But do keep in mind that it's the background signals that lead the NWP! Not the other way around.

And tbh you seem very keen to point out how bad things are and will stay? Yes the Summer lovers are getting frustrated that Summer remains on hold,but you seem to take great satisfaction in that,as you want to hammer home the message numerous times a day.

Perhaps you dislike Summer,and that's your perogative...but I do sense that with you the charts are bang on cue when predicting unsettled conditions,but completely wide of the mark when predicting proper Summer.

The teleconnections could be wrong this time around,but that's not to say they will be wrong all the time....this could be more of a case of a delay rather than a fail. But most definitely I give credit to those that put so much work into them.

EPS & GEFS extended ensemble members now starting to pick up on split flow in both the Atlantic & across Europe into early August. Chaotic & erratic still, but at last starting to at least reconcile the long suggested diagnostic with some kind of numerical model interpretation of it.

This change in downstream flow increasingly likely to assist cut off lows to the west and south west of Europe at the same time as a downstream ridge ultimately replaces the N European trough. Additionally, the sinking motion across N Africa that has led to the intense 600 dam furnace anticyclone subsides as downstream jet flow reconfigures, leading to the static heat across S Europe becoming more mobile as moist Atlantic air bumps up against the stagnant heat. This implies, eventually, forward momentum developing on a thermal boundary to create a potential thundery low mechanism and advect the heat pool further north and east as cooler air tries to come in behind across SW Europe.

So that is a latest updated suggestion for the further outlook.

Still some way off in meteorological terms? Yes it is.

Considerably delayed from initial expectations? Most certainly & emphatically yes.

Guesswork, tea leaves etc etc and other similar nonsense from parochial observers? Mostly emphatically & certainly not..... Alas that type of baiting is what creates a brain drain and drives people away from places like these.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4891808

[bluearmy]

Now we’re down to T60 on my eps watch for the 22nd

lesson - don’t diss the eps mean at 15 days!

 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892040

[Kirkcaldy Weather]

So going back to the end of June which is when the progression of the current pattern began 

The pressure from June 28th > July 17th 

Not really a shock seeing further abnormal developments given the overall continuation is of a similar theme 

Once more connecting with phases 5 - 7 of the MJO brilliant seeing further good matchups

 

I did mention an expectation for a switch with a high to the southeast of the UK potentially moving across the UK and / or Scandinavia which links to phases 8&1 

"I get a vibe that could be via high pressure developing through Europe sat to our Southeast potentially further retrogression up across UK and / or Scandinavia"

Taking the setup currently and putting next to the phase 8 expectation 

The similarities to the high pressure areas are another top quality match with 1 major exception The UK through Scandinavia, what is the reason for this?

With El Ninò having an ever increasing imprint with the setups here lies the reason as Ninò phase 1 for June + July 

Bingo with the signal for a continuation of the pattern since June 28th and more lows from the UK across Scandi with further agreeing using the general phase 1 expectation for July 

Where do I see us going for the remainder of July into weeks 1 possibly 2 of August?

A lot of complexities to decipher (note there are no composites for Ninò July phase 2)

Beginning at phase 2/3.

 

 w/Ninò 

As we've had a super slow travel within these phases it makes a bunch of sense that our pattern currently is progressing at an equally slow pace

Some focal points I'm seeing to watch for as we get toward August

• Further signs for high pressure developments in Scandinavia which was the original thoughts 
• Still some stagnant lows possibly on a northwest - southeast trajectory through the UK
• Be looking at Russia / Siberia for a quite significant high which extends toward the Pacific 

Taking the progress from phase 3 definitely a common theme for a raise in heights in the Atlantic with potential to extend into the UK possibly trending to some settled weather for August week 2 -- Mid August which probably fits with the expectations of @Tamara and @MattH ?

Putting the expected scenario with Ninò phase 3 similar idea and given the atmosphere is still adapting to a proper Ninò state I wouldn't be too concerned with the low pressure signal for Russia / Siberia as the trends evolving suggest the opposite as mentioned 

Latest CFS in line with my thoughts

 

So Taking a trip globally what conditions have developed lately?

Parts of India near the border with Tibet especially Ladakh are witnessing abnormal SNOWFALLS which trapped many hundreds of tourists 

Incredibly more snow will be falling across similar regions 

Some daily record high temperatures are occurring focused on TX,AZ,CA associated with the elongated high mentioned in my post here 

That's not telling the full story for California as the INSANE BONKERS snowfalls in winter are still setting records for the largest snowpack ever in July 

Result being scenes you could actually assume as a picture taken in mid December rather than peak summer aka mid JULY

Further eye catching temp anomalies for the first 2 weeks of July the heat mentioned plus wide coverage of massively below avg 

"I've also marked the persistent low spinning away through parts of Canada this will be causing a massive cold anomaly with a big bullseye across the Dakotas I certainly won't be shocked seeing record low temps from this which slides toward the great lakes during week 2"

Also a concerning amount of Flash Flood scenarios across MULTIPLE states in the U.S & Japan,South Korea, Monsoon regions. 

In Italy looks like the most severe of the temperatures will peak on Monday + Tuesday with record values being a distinct possibility, I know some reports that Rome set a new high temperature yesterday but you can see basically all of Italy being covered by the record territory conditions come Monday + Tuesday.

Needs noting too there will be near record cold air across Shetland & Orkney seeing the 0C 850hpa there  

Just wonder if a big player in helping the high development across Russia / Siberia will be rossby wave activity certainly has that look

Discrepancies continue on the speed with the emerging MJO cycle with regards to date of arriving in the Pacific. CANM which I believe is the GEM, CFS and the BOMM (EXT especially) are the most aggressive with higher amplitude 

 

Wouldn't be totally surprised for a brief extension within phase 5, interesting seeing the GEFS and CFS with the slower progression 

As I started this post yesterday the update today confirms my thinking to an extention within phase 5

Regardless my thoughts are very much in line with the tweet below and similar conversations on Twitter, majority of the hurricane outlooks still keen for a highly active season and typically the WWBs that originate from the associated MJO Pacific activity usually notch the ENSO region SST values up highest so this is likely THE cycle which is going to determine the peak C of this Ninò AND any activity that can be sparked across the MDR (maybe a few in the Atlantic with higher than avg SSTs still present) leading on from this Pacific based MJO action starting early-mid August)

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892429

[johnholmes]

And another 24 hours issued Thursday evening 20 July, with the 500 mb NOAA charts

The trough continues to ease out and the Greenland ridge has pretty much gone, so a quick look suggests we are getting into a mainly westerly and on the 8-14, at long last, from the meridional pattern. However, stubbornly, the UK contours continue to come from the Arctic region so no noticeable warming likely. Also the strength of the flow down to lower France is too great to allow, yet, and push north from Iberia for example.

So the wait for a significant change in weather type continues, at least in my view. That said the major trough over the eastern seaboard does tend very slightly to be backing s of west which may help things in the 14—18 day time scale, we have to wait and see if predictions from longer term models become more supportive.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892667

[Tamara]

15 hours ago, pyrotech said:

The models are showing exactly what you would expect them to show. This unsettled period has been on the cards and shown by the MJO prediction.

We will see an improvement as the MJO will go into phase 6 early August so around 10th of August high pressure is highly likely around North West Europe. 

 

I am quite surprised at some of the more seasoned posters on here as they understand the MJO.

This is a main driver of our weather and watch the models respond to this as we head towards August.

We have been in the wrong phases and in the Circle of death for July and finally looking to break free with the 10 - 14 day lag for us in UK

 

Its been said many many times that it is not as simple as taking the MJO in isolation to gauge weather patterns over a period of time. The MJO is just one part of the total global aggregate wind flow budget. Consideration of the extra tropics is required to gauge the full picture - as propagation of tropical convection propagates between the tropics>extra tropics and there is no linear progression as the two do not always interact equally.

Late Spring & early summer did see a harmonious wind-flow signal between tropics & extra tropics with vast amounts of +AAM anomalies within the entire aggregate atmospheric circulation. The May surging peak in global +ve AAM lagged the feedbacks for a  4 to 6 week period.

So the late Spring inertia provided the platform that led to the very anticyclonic wavebreaking pattern in June in N Europe.

Since then, it is true that tropical convection went in to a lull period. This was anticipated - but what was not anticipated was the more profound effect than was expected that this had within the extra tropical circulation and the amount of -ve inertia c/o strong uptick in trade winds at, and east of the dateline in the Pacific that scrubbed out so much of the anomalously westerly (+ve) inertia from the early summer.

The tropical convergence outcome well west of the dateline has been more reminiscent of a La Nina pattern - with a retrograde upstream mechanism in the Pacific leading to a retracted pattern downstream with a trough replacing the anticyclonic block across N Europe

A slow process is now coming into view to start to reverse the mid summer disconnect and add back some of the westerly inertia lost from global windflow- but again it will be necessary to consider the extra tropical Global Wind Oscillation (GWO) response which depicts aggregate windflow in both tropics & extra tropics - and not the MJO, in isolation.

In this respect, MJO composite,, do not always give a full picture b/c they risk assuming a linear extra tropical response according to the selected composite related to either a La Nina or El Nino forcing. Composite analysis can be erroneous b/c it assumes fixed given parameters within the tropics that do not always correspond to a fixed projected outcome in the extra tropics. 

The constant flux of the atmospheric circulation requires that each wind-flow exchange requires analysis according to its merits and not an x+y = assumption. It is also true that superimposed extra warming is skewing responses based on so many micro scale escalated anomalies creating enough "local" global extremes to strain the overall responses that Mother Nature put in place.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892713

[tight isobar]

3 minutes ago, JayAlmeida said:

Surely a negative CET is now on the cards for July if the model forecasting for the next 10 days verifies.

Certainly. A nego- CET is on the books for July as a whole now....however  the AGM is slowly  coming into forcing...don't  write off August  as the monster month......for Heat transfer. Into our latitude..A close eye needed !!

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892725

[Tamara]

3 minutes ago, Downburst said:

Where’s the plumes?

Its a good question.  

Velocity potential (VP) convection anomaly predictions have persisted with the idea of convergence shifting across the Central Pacific to return a more classic El Nino synoptic response. Much of discussion analysis has been focussed on this - quite reasonably so.

Over recent weeks these predictions have backtracked a few times, putting back the shift in the low frequency signal.  Its worth looking at a water profile across the tropics in this respect. This first image below is almost a week old, but very little has changed. The most intensely anomalous heat is focussed across Indonesia and relatively limited spread also across the Western Pacific. Strong trade winds persists at, and east of the dateline (shaded blue on Hovmollers plot in the third image). Convergence therefore mimics a more La Nina feedback pattern. Look where the main VP200 anomalies (shaded green) lie on the respective plot on the second image. The core is a long way further west of a typical El Nino convergence feedback & with suppression (shaded orange) at and east of the dateline.

With so much heat in these areas well west of the dateline, it does call into question the vivacity of this El Nino, when repeated predictions of eastward progression of tropical convergence and associated westerly wind bursts is being delayed and watered down each time.

The implication of that is the synoptic pattern response is bogged down with Nina feedbacks overshadowing the ocean base state El Nino transition.

This type of oceanic > atmosphere feedback increases the likelihood of return to La Nina much sooner than has been widely anticipated and goes some way to further answering the longevity of the Nino disconnect as discussed already in much detail. In turn explaining the forcing from upstream which has been delaying synoptic upturn for N Europe at the same time as trapping heat across S Europe (Thankfully Portugal has had enough Atlantic influence and effective air con to avoid the worst of the July heat to date).

The numerical models in response to these delays is to water down the expected split flow solutions across the Atlantic & Europe in extended modelling and retain the more retracted pattern which feeds downstream troughs across N Europe at the same time as the Azores/Atlantic ridge is withdrawn. This, rather than a ridge extending fully NE and then the split flow creating cut off lows behind it - which in turn create the ability for warm air (heat) advection northwards.

Clearly, with these spatial wind-flow and VP200 anomalies in mind, it is worth exercising caution with forecasts and keep watching the discussed developments upstream. 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4893247

[Derecho]

So looking at the EC (left) and GFS (right) side by side this morning....

Today - A showery picture, with showers most frequent in the north-east

Saturday - Still a piece of turd with the GFS perhaps a bit slower bringing the rain across.

Sunday - Uncertain but some persistent rain could get stuck over northern England with showers further south. Low confidence on exact position of this rain and whether it will quickly fizzle out as it moves south on Sunday night or keep going.

Monday - Nothing much of note really, a few showers here and there

Tuesday - More showers in the east, perhaps sunnier in the south-west as EC throws up a small ridge.

Wednesday - OK for southern areas early on but some rain pushing in across the west later. Thursday looks reasonable.

Into the weekend - What would this July be without more unsettled weather at the weekend? EC looks the more unsettled in my eyes.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4892675

[mushymanrob]

Troughing set to remain dominant in a mean Westerly flow into August


which can be seen on the GFS average for ten days time,


and theres not much change in 2 weeks time although imho these charts are closer to average


Yet again this chart suggests any return to high pressure dominance has now been put back until the 15th at the earliest


To me, the first half of August is looking average which isnt bad , but its not settled and there no real warmth/heat away from the Southeast.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4893738

[Kirkcaldy Weather]

I've held back from addressing this for long enough 

On 14/07/2023 at 22:37, TSNWK said:

In my view you can have as many global teleconnections theories  as you like  (they tend to come in fads  until proven wrong )  but the simple fact of the  matter is the chaos and  butterfly effect that increasingly extrapolates its own merry dance the further out we look..  an elephant fart in Thailand could introduce the butterfly effect that along with random chaos of the atmospheres scuppers any teleconnections theory beyond around 3 weeks in my humble opinion. Personally I do find the 500mb charts broadly there for two weeks out with detail following within that framework far more often than not.

 

On 15/07/2023 at 11:17, Uncle_Barty said:

I guess the lesson to work out here is *why* there is this disconnect between the oceanic base state and the atmosphere, whether there were any signs of this beforehand, and if/how this can be foreseen in future.

In any case, I've always regarded the various teleconnecions (as excellently set out by Tamara and others... when I get the chance, I still need to get a proper handle on them.. been looking on Youtube for some "dummies" guide on how to read the various charts,) as a guide as to what may be down the line, and certainly not as a firm prediction.

I still remember 2011, when after a poor June, general hope from the various indicators was for a much better July based on seasonal wavelength changes... then the goalposts were moved and we ended up with a crap July anyway.

 

On 15/07/2023 at 10:28, Scorcher said:

I don't understand what pleasure anyone takes watching the models in periods like this- apart from those people who enjoy wishing summer away (I know a few do).

It's monotonous, depressing and there is absolutely nothing of interest- the worst possible setup. It's pointless even looking.

If it's September by that point it won't matter, as it simply isn't the same- doesn't feel like summer even if it's hot.

 

On 16/07/2023 at 22:07, ANYWEATHER said:

Complete waste of time ,teleconections , computer output.....! 

 

On 17/07/2023 at 18:54, Optimus Prime said:

But haven't we just left an extended dry period !!

 

On 19/07/2023 at 09:24, ANYWEATHER said:

The desperation for people to see some summer like charts are becoming more apparent with their frustration on the current weather and output. Yes the weather will improve at some point, but with the failure of long range computer models and teleconections forecasts gone horribly wrong ,for me personally! I have little faith in charts and forecasts away from the current dross that's shown.  

 

On 21/07/2023 at 10:55, JayAlmeida said:

So stuck in circle of doom = summer over

 

On 21/07/2023 at 22:49, ANYWEATHER said:

Gfs although slagged off to death has been Paramount in its output for the last 5 or 6 weeks for the massive change we have seen against all teleconections forecasts.  All the High furluting forecasts from  professional meteorologists on here and elsewhere beg the questions about all long range forecasts.  Yes interesting is the old MJO , PDO , IDO NAO, etc , but they cannot get long range forecasts right. , There are missing links in the Ocillations,  

 

I'd like to address the posts tarnishing the entire suite of teleconnections, I'm always left baffled at the members who continue to disregard the teleconnections and in turn show blatant disrespect to those of us that base our model thread posting on the ever evolving nature of said teleconnective output. Personally I put many hours into my outlook work and don't appreciate the demeaning tone in evidence in a number of the quoted posts above (no targeting just these members these just happen to be the most recent examples that tie into this which is much overdue as this has been happening for a number of years) 

Having seen the descriptions such as ["fads" "waste of time" "buzz words" and somehow a generalised view by some members that they simply are non existent]

The teleconnections do indeed exist, they are the "how" at the core of the weather patterns linked to the charts that the model suites process on a daily cycle 00z-18z. Starting at @TSNWK stating "along with random chaos of the atmospheres scuppers any teleconnections theory" 

There is no theory, the teleconnections contain many processes & dynamics (this also applies to the so called 'random chaos of the atmosphere') 

I've given this excellent link in a post in the past it is one of the best detailed insight into some of the processes + dynamics I'm speaking of 

What are teleconnections? Connecting Earth's climate patterns via global information superhighways | NOAA Climate.gov

WWW.CLIMATE.GOV

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Two guest bloggers explain how Rossby waves create a globe-spanning superhighway that connects climate patterns even when they are far apart.

Next @JayAlmeida stating "So stuck in circle of doom = summer over" this might be perceived as a question or another annoyance which is the 'summer is over' statements I'll address this separately in a short while. IF it was a question I answered and spoke of how this terminology/mindset is incorrect and overused when MJO forecasts go in the O. All this part of the MJO phase spectrum means is lower amplitude equating to adjacent phase(s) because the MJO has an always active state at differentiating amplitudes.

The MJO is one of the biggest contributing teleconnections in the development of  weather patterns globally, I think that's another massive problem with the members who only say 'summers over' 'groundhog day' 'never changing setup' etc and 99% they never provide ANY charts or relevant info. Thinking the patterns over a broadscale will shift at the drop of a hat ain't gonna happen,with a slow pace of MJO of late, an increasingly imprinting Ninò an emerging MJO cycle of SUPER importance tied to Ninò peak C and hurricane developments in the balance the atmosphere requires time to fully process these developments and thus equal patience remains a requirement in regard to the process of trough and unsettled weather for the UK and Scandinavia in particular toward that of a high which I've spoke about. 

@Optimus Prime makes a valid statement which quite unbelievably the conditions which were present throughout June have been forgotten by the folk claiming the summer is somehow over ... Complete nonsense. I think some faults within this is a word association type situation, examples such as Summer > sun , Blue > Ocean this and the OTT expectations of those becoming angry that dry sunny and warm conditions haven't remained for the entire summer season, some seasonal months take on drier patterns akin to June some will be more rainfall dominant akin to the conditions in July that's part and parcel of the dynamics and changeability within the teleconnective process. The changeable variations involved are a large fun factor in the meteorological world from my perspective I'm sure others will think similarly despite the tone within Scorchers post

.

Focusing at the many claims by anyweather the reality is the exact opposite, the teleconnective suite contains the best insight to patterns which are most likely to come to fruition though an importance comes at interpretating the processes associated correctly, the opening sentence of this MJO paper emphasises this post 

Frontiers | Comparison of Madden-Julian oscillation in three super El Niño events

WWW.FRONTIERSIN.ORG

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This paper investigated the characteristics of Madden-Julian Oscillation (MJO) in three super El Niño events (i.e., 1982/83, 1997/98 and 2015/16 El Niño events) based on...

 

'Madden-Julian Oscillation (MJO) is the most important component of tropical atmospheric intraseasonal oscillation (Madden and Julian, 1971; Madden and Julian, 1972), and is also the bridge between weather and climate, which means that MJO plays a critical role in the anomalous weather and climate in many regions (Zhang, 2013; Li et al., 2014; Li et al., 2020).'

@Uncle_Barty a big percentage of the stuff I learnt on stratospheric related phenomena was via online paper sites usually agupubs is loaded with excellent material also on the other teleconnective related stuff

The evolution for the setup which I covered in my previous post appearing already as the dynamics from MJO phases 2+3 take shape accompanying this will be the atmosphere returning to the retrogressive tendency seen since April linked to yet again stratospheric- tropospheric coupling, good representation of this on the Polar height data from Judah Cohen again

 

 

 

 

 

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4894724

[Northernlights]

One of the big issues in the contrasting weather we have had this summer is now showing up in spring barley crops on sandy or gravelly soils in this area as ripening crops have  large patches of fresh green crop emerging .This is what is known as second growth as plants put up secondary tillers when moisture levels in soil return to normal as the drought from  June eases. This is going to cause some very poor samples this harvest.  Not unusual but have never seen it on this scale before perhaps 20% of a field

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4894329

[MattH]

Morning.

One has to acknowledge the 'painful' progression that this summer has taken, since late June all linked to the fall in AAM, as well advertised and discussed for some time. A few weeks ago I provided a screenshot of a piece of work on the long-range outlook with the phrase "locked in for some time" within it; even I have been surprised and incorrect about how long this cyclonic pattern has persisted. While I still don't think this summer can be compared with the likes of 2012, 2007 et al, as yet, the broader evolution (yet again!) of the best weather arriving earlier in the summer, or late spring, and then the proverbial 'wheels coming off scenario', is playing out again this summer. We have seen this a handful of times say in the last 10 to 15 years. Is this perhaps becoming a more common occurrence due to global warming and all the unusual unknowns in play?, possible, but hard to tell - It is clear, however, that we are certainly in a period of heightened uncertainty and questions, more generally, than say 10, 20, 30 years ago, due to the way global warming is influencing the climate at an ever rapid rate.

AGW aside and the AAM and the Pacific developments have and are now evolving as long predicted, we can see that in both model and observed data...

However, there is still little evidence of the AAM patterns and anomalies that were present in May and June. Clearly, this current rise in AAM is not as significant as back in May, equally, the AAM is also rising from an unexpectedly low point too. There are some 'messy' solutions now within NWP showing up in the long-term, but still, no clear-cut signal for the Atlantic trough and downstream ridge pattern before the opening week of August has passed, so that's another week gone.

While I can be far from certain, when working over the weekend I was looking at the QBO and wondering whether the influence of this, as some have picked up on in here, could well be a player this summer, more so than was envisaged and/or expected. As is the case during the winter, in a changing QBO phase the lower levels of the stratosphere can be 'washed out', not a particularly scientific phrase, but it does highlight the situation well. Last summer, it was generally the opposite.

We are now well within a strong East Descending phase, the E'ly winds are now down to 30hPa (all very interesting for the winter!), beneath this and the W'lies are still in play - Is there some scope to suggest that this transitional phase of the QBO has arrived at the wrong time, to aid in juicing up the W'lies and the PFJ as the summer has ticked by? - I suggest it could well be. Since May and June, the QBO has continued to become more E'ly in the upper levels, flushing down the more W'ly anomalies, has this reinforced a more active jet stream pattern, especially when coupled with a complete breakdown in the +ve AAM pattern that dominated the late spring and early summer.

It's a piece of the jigsaw puzzle that is open for discussion, but while there has been an underestimation of how far AAM has fallen and, how, Tamara mentioned a few days ago, the atmospheric pattern, in particular, has resembled a more Nina regime, I feel there may well be more at play than just the GSDM/AAM this summer now.

I still think this rise in AAM will help to at least alleviate the pattern that has dominated the last 4-5 weeks, but will it bring us a solid 2-week spell of 'high summer' weather through August, I'm beginning to think not, especially seeing that it is likely that AAM will take something of a fall again through the second half of August. The additional complication through August as well will be remnant tropical features, as we all know sometimes these can help to bring some summer weather, but also reinforce a more cyclonic pattern too, that, however, is all for the short-term.

For now, a case of 'more of the same' as the summer increasingly quickly rattles on...

Cheers, Matt.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4895291

[mushymanrob]

3 hours ago, Snowy L said:

Met Office say very little about ENSO effects on UK weather but the one thing they feel confident enough to say is the increased likelihood of cold winters during El Nino years.

 

What are El Niño and La Niña?

WWW.METOFFICE.GOV.UK

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El Niño and La Niña are terms which describe the biggest fluctuation in the Earth's climate system and can have consequences across the globe.

 

The stats dont support that, El Nino Winters since 1990 (when warming started getting going) - 91/2, 94/5, 97/8, 02/3, 04/5, 06/7, 09/10, 14/5. 15/6, 18/9  all these were El Nino for the full 3 months.......... out of those ten , only 09/10 produced any cold/snow. the rest were mild and wet (ok there were some minor snow events in some years).... plus the sst anomaly in the Atlantic would suggest milder more likely.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4896000

[Tamara]

On 22/07/2023 at 12:22, Tamara said:

Velocity potential (VP) convection anomaly predictions have persisted with the idea of convergence shifting across the Central Pacific to return a more classic El Nino synoptic response. Much of discussion analysis has been focussed on this - quite reasonably so.

Over recent weeks these predictions have backtracked a few times, putting back the shift in the low frequency signal.

There is no clear sign still of this situation changing. Quite the reverse from late Spring and early Summer generally expressed expectations. Indeed thoughts expressed earlier in July have been consigned to history. Probably one of the most challenging seasons, in general, to decode - but then there are some answers as always to be found.

What also is contributing to the feedback loop in the Atlantic/European sector is ridiculously warm (hot) waters in the NW Atlantic and off the Newfoundland coast which is superimposing the macro scale tropical>extra tropical feedback with the feedback ridging aligning this anomaly and amplifying the effects of deeper troughs running around the perimeter of the Atlantic ridge towards NW Europe within the defined stuck wave pattern. An unusual thermal gradient for summer is created along the polar front as this anomalous heat clashes with the colder air north of the jet stream path The feedback is self perpetuating - the longer the ridge pattern holds, the more the static pattern increasingly allows the regional SST's to increase. And so on and so forth. For UK & NW Europe, this feedback matters - because it is immediately downstream.

From a Portuguese point of view, the unexpected broad scale summer pattern has actually done the country a favour with enough Atlantic wind-flow incidence based on the position of the Azores/Atlantic ridge to the west, and the passage of a few very weak trailing fronts from the N European troughs to allow an aircon effect through most of July. These fronts have produced barely any rain, away from NW Iberian coasts, but have been just about enough to keep the worst of the inferno upper air temperature profiles to the east.

The predictions, in line with much of the expressed thinking heading into the summer, braced the country for the type of dangerously hot and damaging conditions seen across the Mediterranean to the east. So IMBY, (but with August still to come), there is a lot of gratitude so far in contrast to the feelings of many in the UK stuck under the N European trough. Just another, very different,perspective that shows that dangerous blazing heat is worse in many respect than the tiresome dirge of unseasonably wet & unsettled conditions which spoil summer activity, but in themselves are not harmful to people, animals, infrastructure & very much so the environment.

No-one should doubt how superimposed warming is skewing the feedbacks and exaggerating and distorting naturally expected synoptic pattern responses. It does NOT debunk the diagnostic science that studies the natural feedbacks  - but, as stated recently, it does reinforce the message that forecasting based on historical composites are increasingly prone to error and patterns, as they evolve, need to be taken on their own merits.

Some of the very abnormal arctic, ocean and landmass heat anomalies around the globe are creating so many stark and intense micro scale feedbacks that the sum of all these is grossly distorting expected synoptic feedbacks on the larger scale

It is actually very worrying. No-one should underestimate this.

Ambivalent as I am and with no personal interest in cold weather outcomes for the UK in winter, this taking patterns on their merits approach should be adopted especially from this autumn, to save a lot of time and energy in trying to fit desired outcomes into composite frameworks which climate forcing is making more and more redundant as each year passes. This is all happening very fast. Whether it is to do with forecasting, or simply living from month to month, year to year,  people who remain complacent and/or in denial need to wake up.

1 hour ago, Nick2373 said:

Credit to anyone who called July to be this big hum dinger 

If I may respectfully ask - why exactly?

There is a big difference between defining the outcome of a month based on emotion/pessimism (or as per a minority of daily suspects, simply to childishly goad reaction and wind-up people)  - and the people who are often the targets of reactions who take time out to try and offer some suggestions and then who are gloated at with pleasure when expectations are missed. Various posters have pointed this out, including the very good summary made by @Kirkcaldy Weather fairly recently.

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4896443

[Kirkcaldy Weather]

A gradual shift in association with multiple dynamics still coming together nicely, I'd like to delve deeper into a few intriguing situations that will be occuring over the next 3-perhaps 4 weeks, starting with an emerging tropical wave from Africa which likely causes a tropical system to develop within the MDR 

 

This then curves northeastwards, interacts with the jet and to me looks like quite substantial rossby wave breaking within the Atlantic. 

With retrogression upcoming we can see that especially prominent as a trough develops offshore from the U.S west coast and gets drawn WESTWARDS through a section of the pacific, the higher pressure in the interior parts of Canada will absorb part of the energy within the high centred along the southern states 

 

Interesting signs for a shot at dual Pacific tropical systems 

 

The shifting of shear pattern evident also with the end of week 2 taking the look that would be supportive of tropical developments with a path toward the US beyond week 2 which I'll get to shortly 

Another retrogressive move with the zonal winds fitting to the pattern shifts mentioned above   

Most of the significant changing aspects in the shorter term are occuring outwith the UK however the direction very much aligning within setups evolving thanks to phases 2-3 

 

Quite the appearance as we move into weeks 3&4 which is August weeks 2>4

I'd not be one bit surprised for Tropical - Hurricane development ranging from the Caribbean Island chain > Miami > North + South Carolina. Lower possibility but I wouldn't exclude the Mid Atlantic either 

Lots of intriguing prospects as the calendar shifts to August ️🌤

 

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4896621

[snowking]

54 minutes ago, Tamara said:

Some of the very abnormal arctic, ocean and landmass heat anomalies around the globe are creating so many stark and intense micro scale feedbacks that the sum of all these is grossly distorting expected synoptic feedbacks on the larger scale

 

This is an absolutely crucial point, and it's something which has been noticeable on a smaller scale now for a number of years from what I have observed, but there's no doubt that this summer is by far the starkest example of successions of micro overriding the expected macro.

There are many places to look for the causes of these micro scale feedbacks but we have to start by looking at the oceans :

With that level of hemispheric anomalous warmth we have to pretty much throw out the rulebook on everything we have all so diligently tried to get a handle on during the last 15-20 years (few more so than yourself @Tamara) and start to apply further new learning.

Unfortunately with the world changing so fast now I suspect this learning and re-learning is going to manifest in ever smaller cycles.

Nobody has been able to call the medium to long range over the past few months utilising any source, and for very good reason. 

The only predictable thing is that tantrums on here will increase at several standard deviations above the expected rate as things become more chaotic.

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4896487

[Mike Poole]

I agree with above posts, I don’t think sustained settled spell is on the cards.  I think the two GFS runs this morning from day 8 onwards indicate the likely way forward:

Both show a ridge moving in, but then continuing to move east, as less settled weather moves in behind, then a ridge builds once more, rinse and repeat.  A million miles better than being in a stuck pattern with a trough over us, like July, but a more mobile pattern that has any settled warm spells punctuated by less settled spells.  

I still think an all out settled spell will probably have to wait until September.  

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4898066

[bluearmy]

A couple of days ago the ec op began to play with a highly anomolous nw Russian upper ridge at day 10. If that happens and sticks then I’m not sure what will follow for our part of nw europe because that’s going to block the jet 

move on 48 hours and the ops all see the feature but deal with it differently (but all with a strong retrograde pattern on it). if it simply heads to Greenland locale then we roughly know what to expect.  However, we also see an Azores upper ridge likely to push across at a similar timeframe - the chance is there that what could look like a transient Azores feature running west to east could find itself with a mate heading east to west at the same time. If that plays out how those seeking a summery august want, then we do get a more significant block establishing in the e Atlantic/nw European sector.  perhaps a route to getting next week’s improvement to stick around ???

Original post: https://community.netweather.tv/topic/99056-model-output-discussion-mid-summer-onwards/?do=findComment&comment=4898359