Model Output Discussion - Mid Summer Onwards

[ItNeverSnowsInWindsor]

Look at that contrast between NW Europe and South Europe!

[mushymanrob]

Every sign in deep FI of an improvement keep getting shunted back


The GFS mean


EPS


There charts not only are consistent and agree , but are a million miles away from any pattern that would bring warmth/heat. To me the outlook for the rest on the Month suggests below average unsettled.

Edited July 14, 2023 by mushymanrob

[Downburst]

That tropical storm is hanging around inside the Azores High, probably giving the High right old headache. Amazing really the way it's bouncing about. If I am not mistaken they usually break free and head up towards Newfoundland area. 

[johnholmes]

Have to agree with the post by mushy just above, to me neither the 5-10 nor the 8-14 NOAA anomaly charts give any indication of heat. Looking at the contour heights on 6-10 and 8-14, in the UK area, they continue to rise slowly, but, the origin continues to be from polar regions. One has to follow the contour over southern France/northern Iberia, before finding one that does not. Also the 500 flow is too strong to allow any northward push of warmer air. 14 days =28 July!

Notice also the ridge-trough set up in the far eastern Pacific, that will impinge on the European area. To me it does not look like a hot even very warm start to August. The odd day maybe but that would be about all.

Closer to now then the deepening low over the SW is going to make camping in many parts a bit of a no go over this weekend, strong to gale force winds coming in behind the surface low as it tracks N-NNE.

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

 

[mb018538]

AAM is only beginning to sharply rise in the coming days….just have to hope this is enough to move the stuck pattern along towards the end of the month. Models really not interested in anything other than a continuation of what we’ve got.

[Addicks Fan 1981]

2 minutes ago, mb018538 said:

AAM is only beginning to sharply rise in the coming days….just have to hope this is enough to move the stuck pattern along towards the end of the month. Models really not interested in anything other than a continuation of what we’ve got.

Not that I am trained or anything like that but I do think that the NWP is representing our AAM of 5 days ago.  A lag effect in other words so for the next 5 days I would assume our weather will correlate to the AAM being the way it is now.    

[Downburst]

5 minutes ago, Addicks Fan 1981 said:

Not that I am trained or anything like that but I do think that the NWP is representing our AAM of 5 days ago.  A lag effect in other words so for the next 5 days I would assume our weather will correlate to the AAM being the way it is now.    

My thought on this. The AAM is a computational measure, measuring angular momentum of the atmosphere with predictions into the future from a starting point of data. The NWP models we generally look at are the same, with initial conditions. There is no lag in the NWP compared to an index of AAM. The 500 charts presented this morning are as good as you might find in predicting the weather. the predictive chart you show for AAM is just that and in my view there is no lag as such, initial conditions are just that for any predictive system with respect to weather. If this AAM was able to over ride ECM or NOAA or MET Office general output data,  I think the scientists in there had better get to work chasing up these charts. 

Summary, don't expect the weather you want because world wide AAM rises, you may as well expect the weather you don't want BTW.

[JayAlmeida]

The GFS is really keen on keeping the unsettled theme going in the reliable with all improvements being meagre and only really being positive if you compare them to what we currently have. Summer doesn't really get a foothold until the final frame.

The ECM and GEM keep showing tentative signs of improvement but it always seems to be at @+240 hrs with each run. This generally means any improvement is stuck in limbo.

Earlier in the week it was looking like things could start improving by the 20/21st but its been pushed back every day since until the 24th and I wouldn't be surprised if this push back continued.

Edited July 14, 2023 by JayAlmeida

[Snowman.]

Persistence of the mid Atlantic block and shallow trough N/NE is frustrating and hard to break. Don’t see things changing for the next 10 days or so. Hopefully we do see improvements soon as the consistent grey cloud and light drizzle is putting a downer on summer. 

[ANYWEATHER]

5 minutes ago, JayAlmeida said:

The GFS is really keen on keeping the unsettled theme going in the reliable with all improvements being meagre and only really being positive if you compare them to what we currently have. Summer doesn't really get a foothold until the final frame.

The ECM and GEM keep showing tentative signs of improvement but it always seems to be at @+240 hrs with each run. This generally means any improvement is stuck in limbo.

Earlier in the week it was looking like things could start improving by the 20/21st but its been pushed back every day since until the 24th and I wouldn't be surprised if this push back continued.

As others on here have said in a nutshell, don’t expect any major improvements before months end ….at least….️

[JayAlmeida]

14 minutes ago, ANYWEATHER said:

As others on here have said in a nutshell, don’t expect any major improvements before months end ….at least….️

June was really good up here but as anyone knows a good june rarely leads to a good summer overall unless its a classic. The way July is shaping up this summer is anything but a classic. Kinda beginning to run out of positives to be fair after three weeks of this dross.

If we're waiting for August to swoop in and save summer anyone who lives in the UK knows how that usually goes down

[danm]

Looking at the models for next week, we are almost stuck between two different weather patterns. The trough departs to the NE, which is a positive, but the high to the W/SW of us struggles to make more than temporary inroads. What we're left with is a pretty uninspiring set up - some sunny spells, probably quite a bit of cloud at times, plus a few showers. Temperatures around average at best. 

It's still an improvement on what we have this weekend, which isn't hard, so a the very least we should have decent amounts of useable weather and in any sunshine it will feel warm due to the time of year. 

Looking at the GFS 6z, we may get some warmer air briefly flirting with the SE on Tuesday:

[Man With Beard]

Unfortunately the ECM clusters gave us one cluster only - and that was one of the worst members for heat! Looking through the individual members by 29th July, it is clear that there are a range of options, though. So, I have very unscientifically attempted to create my own set of clusters. My take on them:

P6: Continuation of the existing pattern - main trough NE, main ridge W, lows likely to keep coming. I felt that between 30% and 50% of members could fall in this "cluster"

P31: Low pressure appears west of the UK, encouraging heights to build on the eastern flank. About 20% of members attempted to do something similar either by shorter or greater measures (although in different ways to the member shown here)

P45: A UK High emerges. Around 15% of members could fall in this camp

P38: The opposite of P45 - a UK low dominates. Again around 15% of members were variations on this theme IMO

The rest were various combinations of these trends, although I'd suggest trending more towards P6 than any other.

The positive I take is that ECM is still undecided about the last few days of July. The betting person would put money on a continuation of the same. Those following background signals that have been mentioned on this forum over the past 48 hours (and actually during the whole of this month so far) might believe that P31 or P45 will emerge over time as front-runners. 

My key takeaway - don't get your hopes up too much, but don't write off the end of July just yet either

 

[Fourty Point Three Degrees]

It is most certainly guaranteed we won't be tapping into the current heatwave in Europe anytime soon.  No sign of any heat coming our way or any warmth of any kind for that matter. 

Edited July 14, 2023 by 38.7°C

[Tamara]

11 minutes ago, Downburst said:

My thought on this. The AAM is a computational measure, measuring angular momentum of the atmosphere with predictions into the future from a starting point of data. The NWP models we generally look at are the same, with initial conditions. There is no lag in the NWP compared to an index of AAM. The 500 charts presented this morning are as good as you might find in predicting the weather. the predictive chart you show for AAM is just that and in my view there is no lag as such, initial conditions are just that for any predictive system with respect to weather. If this AAM was able to over ride ECM or NOAA or MET Office general output data,  I think the scientists in there had better get to work chasing up these charts. 

Summary, don't expect the weather you want because world wide AAM rises, you may as well expect the weather you don't want BTW.

Modelling forecasts from ECM, as a quality example, in respect of AAM will give some insight into the numerical models synoptic outlook.  More reliable in respect of initiation data etc than the CFS vs 2 AAM forecast on that mapwall site. However, if the numerical models (including ECM)  are blindsided by the strength of an existing diagnostic signal this can, and sometimes does, create errors in extrapolating the length of that signal forward. This is the essence of the posts being made of late in terms of trying to urge caution in too much fixation with extended NWP.

With all that in mind, its worth looking again at the actual consolidated GSDM data to try to get some clues as to the longevity of the AAM lull and how it is possible that some blindsiding may increasingly likely to be in operation.

As posted a few times, large amounts of surplus westerly winds ( Nino-esque inertia) have been scrubbed from the extra tropical circulation. These surplus +AAM windflow anomalies ensured the downstream ridging of the first part of the summer. Sub seasonal effects such as the Indian monsoon are now scrambling the low frequency Nino ENSO signal & feedbacks are emanating from a more Nina-esque background in the absence of high frequency forcing in the Pacific which drove the early part of the summer.

The periodicity of the -ve MT is predicated on largescale retrograde effects in both tropical and extra tropical mountain torques. Total aggregate MT in both tropics & extra tropics has fallen this week to -ve 3 standard deviations (from parity). The -ve inertia is identified by the circled anomaly on the plot and the reflected arrowed aggregate STD drop. (There is also -ve inertia corresponded in the SH c/o South America Andes -ve MT processes)

 

Based on the increasingly El Nino-esque base state, a very large disconnect is in process and consequently a very unstable GSDM profile - with the Global Wind Oscillation advertising this disconnect orbiting through GWO Phase 1 which is a La Nina attractor phase. 

Ergo, the atmospheric circulation is acting "destructively" (currently) on the ocean base state c/o this disconnect.

The retrograde -ve inertia phase (easterly) is proving increasingly prolonged. The -ve MT periodicity, as mentioned above, relates to lag timescales of up to 12 days from when westerly winds start to be re-added in the tropics (c/o high frequency MJO/CCKW activity). These initial westerly wind additions are represented by frictional torque momentum (i,e a surface flow inflection convergence point created where these re-added westerly winds meet the easterly inertia that the -ve torqe processes had dumped into the atmospheric circulation)

New WWB additions added can be seen on the equatorial scale of the FT plot. Over time, these propagate through the tropics into the extra tropics

 

Consolidated GSDM data lags by about 2 days. There are signs of an uptick just beginning in the re-addition of WWB's as the next tropical convection cycle propagates eastwards though the tropics. This signal requires a few days monitoring for persistence - hence the suggestion to not jump on each and every day intra day modelling suite - especially based on the lagged periodicity for the existing -ve MT effects to be eradicated from the extra tropical circulation (ahead of the propagation of renewed WWB's)

From all this, it is possible to see how numerical models might be too blindsided by the strength of the prevailing signal (and its periodicity timescale) However, in the outlook period at some stage the numerical models become increasingly likely to screech into reverse as they start to see what is ahead of the roadblock.

The mantra remains that the last third of the summer may ensure a bookended season - with a seasonal disconnect as at present in the middle.

[JayAlmeida]

36 minutes ago, Tamara said:

Modelling forecasts from ECM, as a quality example, in respect of AAM will give some insight into the numerical models synoptic outlook.  More reliable in respect of initiation data etc than the CFS vs 2 AAM forecast on that mapwall site. However, if the numerical models (including ECM)  are blindsided by the strength of an existing diagnostic signal this can, and sometimes does, create errors in extrapolating the length of that signal forward. This is the essence of the posts being made of late in terms of trying to urge caution in too much fixation with extended NWP.

With all that in mind, its worth looking again at the actual consolidated GSDM data to try to get some clues as to the longevity of the AAM lull and how it is possible that some blindsiding may increasingly likely to be in operation.

As posted a few times, large amounts of surplus westerly winds ( Nino-esque inertia) have been scrubbed from the extra tropical circulation. These surplus +AAM windflow anomalies ensured the downstream ridging of the first part of the summer. Sub seasonal effects such as the Indian monsoon are now scrambling the low frequency Nino ENSO signal & feedbacks are emanating from a more Nina-esque background in the absence of high frequency forcing in the Pacific which drove the early part of the summer.

The periodicity of the -ve MT is predicated on largescale retrograde effects in both tropical and extra tropical mountain torques. Total aggregate MT in both tropics & extra tropics has fallen this week to -ve 3 standard deviations (from parity). The -ve inertia is identified by the circled anomaly on the plot and the reflected arrowed aggregate STD drop. (There is also -ve inertia corresponded in the SH c/o South America Andes -ve MT processes)

 

Based on the increasingly El Nino-esque base state, a very large disconnect is in process and consequently a very unstable GSDM profile - with the Global Wind Oscillation advertising this disconnect orbiting through GWO Phase 1 which is a La Nina attractor phase. 

Ergo, the atmospheric circulation is acting "destructively" (currently) on the ocean base state c/o this disconnect.

The retrograde -ve inertia phase (easterly) is proving increasingly prolonged. The -ve MT periodicity, as mentioned above, relates to lag timescales of up to 12 days from when westerly winds start to be re-added in the tropics (c/o high frequency MJO/CCKW activity). These initial westerly wind additions are represented by frictional torque momentum (i,e a surface flow inflection convergence point created where these re-added westerly winds meet the easterly inertia that the -ve torqe processes had dumped into the atmospheric circulation)

New WWB additions added can be seen on the equatorial scale of the FT plot. Over time, these propagate through the tropics into the extra tropics

 

Consolidated GSDM data lags by about 2 days. There are signs of an uptick just beginning in the re-addition of WWB's as the next tropical convection cycle propagates eastwards though the tropics. This signal requires a few days monitoring for persistence - hence the suggestion to not jump on each and every day intra day modelling suite - especially based on the lagged periodicity for the existing -ve MT effects to be eradicated from the extra tropical circulation (ahead of the propagation of renewed WWB's)

From all this, it is possible to see how numerical models might be too blindsided by the strength of the prevailing signal (and its periodicity timescale) However, in the outlook period at some stage the numerical models become increasingly likely to screech into reverse as they start to see what is ahead of the roadblock.

The mantra remains that the last third of the summer may ensure a bookended season - with a seasonal disconnect as at present in the middle.

I admire your optimism and steadfast dedication to the idea of summer returning. I also admire the attention to detail and overall scope of your post(s)

I Just hope it gets a move on sooner rather than later.

Edited July 14, 2023 by JayAlmeida

[Nick2373]

00z Doesn't bring any cheer in terms of warmth a fraction above average to below average up till the 24th-25th, perhaps a hint of something warmer from around then till the 29th then back below average.

this pattern seems to be locked in pretty much like Junes heat, there will be workable days but not wall to wall sunshine the west to North Westley winds look to remain for a while with with the chance of warm or hotter conditions dropping by each run.    

[JayAlmeida]

1 minute ago, Nick2373 said:

00z Doesn't bring any cheer in terms of warmth a fraction above average to below average up till the 24th-25th, perhaps a hint of something warmer from around then till the 29th then back below average.

this pattern seems to be locked in pretty much like Junes heat, there will be workable days but not wall to wall sunshine the west to North Westley winds look to remain for a while with with the chance of warm or hotter conditions dropping by each run.    

As previously posted the Metoffice 10 day update video had a NW flow as the most likely trend til months end so it must be on the money.

[Nick2373]

1 minute ago, JayAlmeida said:

As previously posted the Metoffice 10 day update video had a NW flow as the most likely trend til months end so it must be on the money.

The UK In terms of patterns always seems to get stuck these days for weeks, then when it switches back I've never seen such consistent patterns of late. 

[Djdazzle]

Hoping that something changes soon, especially when most of Europe is basking under blue skies and hot conditions. The UK is dreadfully unlucky.

[Derecho]

25 minutes ago, Djdazzle said:

Hoping that something changes soon, especially when most of Europe is basking under blue skies and hot conditions. The UK is dreadfully unlucky.

At least pressure is increasing so its a reasonable outlook but quite boring.

What we need is to get a decent ridge across us and hope it pushes east.

[Addicks Fan 1981]

58 minutes ago, Djdazzle said:

Hoping that something changes soon, especially when most of Europe is basking under blue skies and hot conditions. The UK is dreadfully unlucky.

Adding to the excellent post from @Tamaraas she always does, we also need to look out for other elementary aspects like the MJO, NAO and AO, examine what they do on a daily basis as well. 

Another reason why our weather is in a rut currently is the MJO is basically inactive. 

The sooner it can get active and more coherent the better our weather will be in essence.   

[Catacol]

Forgive me for jumping in, blindfold on, at this point. My blindfold is on because I haven't been following the forum at all for several months due to a hatred of hayfever, a general dislike of heat and therefore a dread of high summer. For me the current period of temps in the 18-23 bracket are an absolute joy so gnashing of teeth and some stuff I've just scanned about failed midsummer forecasts are chaff in the wind.  Fortunately, winter is coming once again....

What has caught my eye is the disconnect between ENSO base state and the GWO orbit, a reflection of global wind flows. I wonder whether there is a database somewhere of the general state of the ocean/atmospheric connection state over time - to my anecdotal eye and memory we seem to have been regularly experiencing situations where a disconnect exists. You don't have to be a genius to grasp the significance of a disconnect - we know the expected long wave implications of base state and accompanying MJO phase. But when the atmosphere is not behaving as expected (and that plunge to -3 MT illustrated by Tamara above would be an example) it throws everything off kilter. We can correctly conclude that -AAM enhanced by torques like this will eventually bounce back: that is the nature of the relationship between earth and atmosphere, always craving absolutely synergy but constantly experiencing elasticated acceleration and deceleration. At some point there will be a bounce back in momentum and the Nina-style atlantic profile will shift, removing the current trough - but timing, timing, timing.....and so difficult to work out when the atmosphere is off on a tangent, misbehaving and not doing what it should.

What then fascinates me is how such disconnects occur and why (if seems to me to be the case) they are so common - at least these days. We had an atmosphere playing as though we were in a Nino phase during a Nina winter, and now that we have a Nino base state the atmosphere swings the other way. I do not profess to understand why such disconnects occur. I know with absolute certainty that they make longer range forecasting a nightmare. Through the winter we did at least have an MJO that stuck to standard script and allowed some impacts from phases 6/7/8 to be correctly landed - but while the MJO is extremely important it is not the whole picture and I crave a better understanding of disconnected states.

For summer lovers July is looking poor precisely because of this current disconnect, and forecasters who do understand teleconnections will be frustrated because these situations make it look as though the ar*e is about as well understood as the elbow. Not the case. Timing becomes a nightmare. But in the current situation (though I must admit I'm saying this having not looked in any great details as to what is going on) it would be a surprise if a poor August followed a poor July. The disconnect would have to be extreme and the period of -AAM dominant for a very sustained period against a backdrop of growing Nino impacts.

Not really a model related post - so I best finish with something of a model nature to avoid the wrath of those who like NWP output. Signs perhaps of the azores high returning closer to home by week 1 august.

Edited July 14, 2023 by Catacol

[mb018538]

1 minute ago, Catacol said:

Forgive me for jumping in, blindfold on, at this point. My blindfold is on because I haven't been following the forum at all for several months due to a hatred of hayfever, a general dislike of heat and therefore a dread of high summer. For me the current period of temps in the 18-23 bracket are an absolute joy so gnashing of teeth and some stuff I've just scanned about failed midsummer forecasts are chaff in the wind.  Fortunately, winter is coming once again....

What has caught my eye is the disconnect between ENSO base state and the GWO orbit, a reflection of global wind flows. I wonder whether there is a database somewhere of the general state of the ocean/atmospheric connection state over time - to my anecdotal eye and memory we seem to have been regularly experiencing situations where a disconnect exists. You don't have to be a genius to grasp the significance of a disconnect - we know the expected long wave implications of base state and accompanying MJO phase. But when the atmosphere is not behaving as expected (and that plunge to -3 MT illustrated by Tamara above would be an example) it throws everything off kilter. We can correctly conclude that -AAM enhanced by torques like this will eventually bounce back: that is the nature of the relationship between earth and atmosphere, always craving absolutely synergy but constantly experiencing elasticated acceleration and deceleration. At some point there will be a bounce back in momentum and the Nina-style atlantic profile will shift, removing the current trough - but timing, timing, timing.....and so difficult to work out when the atmosphere is off on a tangent, misbehaving and not doing what it should.

What then fascinates me is how such disconnects occur and why (if seems to me to be the case) they are so common - at least these days. We had an atmosphere playing as though we were in a Nino phase during a Nina winter, and now that we have a Nino base state the atmosphere swings the other way. I do not profess to understand why such disconnects occur. I know with absolute certainty that they make longer range forecasting a nightmare. Through the winter we did at least have an MJO that stuck to standard script and allowed some impacts from phases 6/7/8 to be correctly landed - but while the MJO is extremely important it is not the whole picture and I crave a better understanding of disconnected states.

For summer lovers July is looking poor precisely because of this current disconnect, and forecasters who do understand teleconnections will be frustrated because these situations make it look as though the weeble is about as well understood as the elbow. Not the case. Timing becomes a nightmare. But in the current situation (though I must admit I'm saying this having not looked in any great details as to what is going on) it would be a surprise if a poor August followed a poor July. The disconnect would have to be extreme and the period of -AAM dominant for a very sustained period against a backdrop of growing Nino impacts.

Not really a model related post - so I best finish with something of a model nature to avoid the wrath of those who like NWP output. Signs perhaps of the azores high returning closer to home by week 1 august.

I agree - it's a very Nina style set up at the moment, and one that wasn't expected to dominate (hence all of the LRFs going mainly settled, warm and dry). The bounce back is just taking forever. Might take until the very end of the month or early August now to see any proper change.

[Downburst]

1 hour ago, Djdazzle said:

Hoping that something changes soon, especially when most of Europe is basking under blue skies and hot conditions. The UK is dreadfully unlucky.

Luck has nothing to do with it. This is the climate and that's a fact. There are expectations that all summers are summary and the fact is that they are not, or not all the time. Now the last couple of weeks and perhaps another 10 days are simply normal in any give summer.  We take the rough with the smooth here or move to the continent.  I'm not having a dig, but you may as well ask Tamara there to dump the study and grab the dice and let us all know if we are getting a 6.