Model Output Discussion - Mid Summer Onwards

[Derecho]

10 day outlook, EC left and GFS right...

Today - Looks like some heavy showers in the east, the odd banger perhaps

Tomorrow - Showers more widespread but lighter and well scattered in nature with sunny spells between them

Friday - A mostly cloudy day with a bit of patchy rain in places, perhaps something more persistent in western Scotland

Saturday - Yuck, a real stinker of a chart.

Sunday - Uncertainty creeps in, EC goes for a washout over northern England and southern Scotland. Thundery showers further south. GFS has a more muted pattern.

Middle of next week - Returning to something more generic for a time with the GFS throwing up a small ridge... might be as good as it gets.

End of the week - GFS still pushing low pressure across us, unsettled and wet. EC going in a similar direction albeit slower.

Temperature wise... northern Europe the only area of the globe with substantially below average temperatures aside from pockets of cold anomalies in Antarctica. Stuck in a rut!

[ANYWEATHER]

In a nutshell, unsettled all the way ,no sign of settled summery weather even in the Ten day charts of FI........

[CoventryWeather]

10 hours ago, mushymanrob said:

Im not going over this yet again. If you think that then scroll on. I dont care. 

This subject has been done to death, theres a reason why i use these charts as the basic guide ...

That is fine we all have our own personal opinions and I support that. 

Personally still follow on what I stated yesterday, I feel the anomalies will take longer to pick up on a drier and warmer signal. Granted, we may get a few days in and the signal wanes, but the latter parts of the GFS recently has been consistent with the Azores High pushing east and it becoming drier. The ensembles think so too. Let's wait and see what the other models think when it gets to 216/240hrs. 

[ANYWEATHER]

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.  But keep the faith folks ,the weather will improve,  as and when the weather does ☺

[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

 

 

[terrier]

So the schools break up on Friday. And the charts from the ECM & GFS are dire. They were some settled days next week on yesterday’s GFS06Z output but that now seems very unlikely. Seems the order of next week is showers or longer spells of rain. Anyone away in this country next week I feel so sorry for.

[josh-weather]

11 hours ago, Metwatch said:

Why do I have the feeling you don't have access to the GDSM charts? I don't think many non meteorologists can access them to the best of my knowledge.

What is GDSM? I can't find any reference to it except for here

[jules216]

11 minutes ago, 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.  But keep the faith folks ,the weather will improve,  as and when the weather does ☺

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.

[jules216]

5 minutes ago, josh-weather said:

What is GDSM? I can't find any reference to it except for here

Its a subseasonal tool used/created by some now retired NOAA senior meteorologists(Barry,Wieckerman) that calculates a ballance between global wind circulation(budget) vs speed of which Earth turns around its axis. These always seek an equilibrium so where is a complex method how one can try to predict at what lattitude will the westerlies/easterlies increase or decrease based on this budget/ballance.

https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.psl.noaa.gov/map/clim/wb2007_ams.pdf&ved=2ahUKEwitzuHAs5qAAxVISvEDHa2-DOMQFnoECAkQAQ&usg=AOvVaw0kx_Hm2WLuIDTQzT68qE4r

[knocker]

16 minutes ago, josh-weather said:

What is GDSM? I can't find any reference to it except for here

It's the new kid on the block that has replaced Monty Python and the Holy Grail

[MATTWOLVES 3]

1 hour ago, 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.  But keep the faith folks ,the weather will improve,  as and when the weather does ☺

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.

[Man With Beard]

ECM ensembles update for the end of the month ... still less than half of members suggesting a clear-cut change of pattern to something more settled, generally through the Azores High. However, things generally flatter out west (which is a start), and less unsettled to the NE than of late:

The clusters format shows the rather high numbers of possibilities more clearly - the one that continues to elude is the one which might have the best chance of leading to a heatwave - a strong build of heights through central Europe

 

 

 

[northwestsnow]

19 minutes ago, Man With Beard said:

ECM ensembles update for the end of the month ... still less than half of members suggesting a clear-cut change of pattern to something more settled, generally through the Azores High. However, things generally flatter out west (which is a start), and less unsettled to the NE than of late:

The clusters format shows the rather high numbers of possibilities more clearly - the one that continues to elude is the one which might have the best chance of leading to a heatwave - a strong build of heights through central Europe

 

 

 

Only cluster 5 looks anything like ok to me .

The rest suggest the beginning of August looks crap.

 

[Snowy L]

26 minutes ago, northwestsnow said:

Only cluster 5 looks anything like ok to me .

The rest suggest the beginning of August looks crap.

 

2 and 3 at least break the wave 5 pattern. Those are snapshots but would imagine we would at least have more changeable weather (e.g. occasional weak ridges) rather than the fixed endless low pressure influence we have now.

[Bristawl Si]

2 hours ago, CoventryWeather said:

That is fine we all have our own personal opinions and I support that. 

Personally still follow on what I stated yesterday, I feel the anomalies will take longer to pick up on a drier and warmer signal. Granted, we may get a few days in and the signal wanes, but the latter parts of the GFS recently has been consistent with the Azores High pushing east and it becoming drier. The ensembles think so too. Let's wait and see what the other models think when it gets to 216/240hrs. 

The Anomalies -

John Holmes's posts, aided by his long-time 'apprentice', Mushy have been, pretty much spot on over last few weeks.  So, together with latest UK Meto's medium term forecasts, i see no reason to dismiss them.

Been the most reliable weather predictor for this month. 

[Northwest NI]

6 minutes ago, Bristle Si said:

The Anomalies -

John Holmes's posts, aided by his long-time 'apprentice', Mushy have been, pretty much spot on over last few weeks.  So, together with latest UK Meto's medium term forecasts, i see no reason to dismiss them.

Been the most reliable weather predictor for this month. 

If the Anomolies were wrong, would that be an anomaly?

[Rain All Night]

The EC46 seems to possibly be coalescing around a flatter Atlantic than we've seen of late for the first week of August?

Latest GEFS extended for comparison

[TSNWK]

20 minutes ago, Bristle Si said:

The Anomalies -

John Holmes's posts, aided by his long-time 'apprentice', Mushy have been, pretty much spot on over last few weeks.  So, together with latest UK Meto's medium term forecasts, i see no reason to dismiss them.

Been the most reliable weather predictor for this month. 

Fully agree.   Winter as well they are now my goto for broadscale week 2. Anything beyond is subject to chaos and day 10 Op runs have left me with egg on my face and disappointment to many times.

Guesswork / hope / chance and good luck for week 3 and beyond

Anomalies for a framework to work within for week 2

Pretty good confidence on detail now up to day 6

Is how I like to play it now

[mushymanrob]

1 hour ago, Bristle Si said:

The Anomalies -

John Holmes's posts, aided by his long-time 'apprentice', Mushy have been, pretty much spot on over last few weeks.  So, together with latest UK Meto's medium term forecasts, i see no reason to dismiss them.

Been the most reliable weather predictor for this month. 

I also use the EPS now as well, that suite often supports the NOAA but as its a daily slider we can spot minor changes within the NOAA anomaly chart mean. I find using both together when they agree has made them even more accurate, and with the EPS going out a little further, gives us a stronger view of the horizon..

[Man With Beard]

1 hour ago, Bristle Si said:

The Anomalies -

John Holmes's posts, aided by his long-time 'apprentice', Mushy have been, pretty much spot on over last few weeks.  So, together with latest UK Meto's medium term forecasts, i see no reason to dismiss them.

Been the most reliable weather predictor for this month. 

They have been superb recently, yes. I feel they do particularly well when things are stable. The 6-10 chart I feel pretty confident about. During some recent summers the 8-14 has missed a couple of heatwaves. But it's usually a good guide. The problem is probably us - we desire concrete predictions as far into the future as possible, and we're perhaps not as close to that as we'd like especially beyond D10.

[mushymanrob]

38 minutes ago, Man With Beard said:

They have been superb recently, yes. I feel they do particularly well when things are stable. The 6-10 chart I feel pretty confident about. During some recent summers the 8-14 has missed a couple of heatwaves. But it's usually a good guide. The problem is probably us - we desire concrete predictions as far into the future as possible, and we're perhaps not as close to that as we'd like especially beyond D10.

To  "stable" id add "regular" ... as in when we have a regular longwave pattern from the West. They do pick out incoming ridges/troughs very well as a rule.. but blocked patterns is when they arent at their best (but nor is any other tool).
But look at us.... amateurs talking about picking out developing patterns at day ten ! not only from anomalies either... i remember when the pros could get past day three!

Thats a testiment to how far the understanding of our weather has come in conjunction with modern technology.

[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.

Edited July 19, 2023 by reef
Removed non-model discussion

[Methuselah]

I agree, Tamara; how can anyone hope for a prognosis without a diagnosis? But, that said, after-the-fact 'I told you so's' are more than enough for some. Twas ever thus? 

[Downburst]

Quick thanks to Tamara for all the time and effort put into this site. Certainly requires patience along with all the knowledge.

The following charts are possibly a good way of viewing the weeklies, using probabilities to help add weight to the view. This is the latest run.

Next weeks Lower Tercile Probability for Surface Pressure (I'd take that probability gamble to Monte Carlo and put it all on Red)

The week 7 to 14 August is a major improvement over the week before

[Downburst]

8 minutes ago, Methuselah said:

I agree, Tamara; how can anyone hope for a prognosis without a diagnosis? But, that said, after-the-fact 'I told you so's' are more than enough for some. Twas ever thus? 

With a name like yours, you should certainly know it was ever thus