Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Model output discussion 11th July onwards


Recommended Posts

Posted
  • Location: uxbridge middlesex(- also Bampton oxfordshire
  • Weather Preferences: blizzard conditions. ice days
  • Location: uxbridge middlesex(- also Bampton oxfordshire
6 minutes ago, mushymanrob said:

what "sun and heat"?
 

2021-07-23T12 00 00Z-2.png

Plenty ere still -@last hurrah 26 /sunny

DEE49DAC-C1C4-46CE-AC55-C34EE160C299.jpeg

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Sedgley 175metres above sea level
  • Weather Preferences: Any kind of extremes. But the more snow the better.
  • Location: Sedgley 175metres above sea level
4 hours ago, mushymanrob said:

Evidence of the NOAA accuracy?

On the left is the 8-14 day mean issued on July 12th... that covers the period July 20th - 26th, of which today, the 23rd, is mid point therefore should be the closest match.
On the right is the current latest ECM 500mb chart for today.

Azores high just west of the Azores.... check
Low over baffin ..................................... close
Shallow trough to our southwest ........check
High pressure to our near EastNortheast ..check
Strong flow out of USA / Canada tracking over North Scandinavia .... very close.

With repeated chart accuracy in this timeframe, it underlines my POV and why im so keen on them.
 

verification.jpg

I don't dispute your takings on those noaa charts,but it still doesn't alter the fact that most data out to that point will be showing a slight bias towards climatology normal preferences.. Tamara points this out often as do senior met office operators! Any model data at this range can become very confused by misleading or overriding signals! If most of the data becomes clueless at longer range and reverts back to the default Weather pattern.. 8/9 times out of 10 it will be proven correct..

  • Like 4
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North

Whilst I don’t pretend to be a forecaster..I don’t blog or anything like that, I’m just an enthusiastic amateur who loves the weather..  ...I have noticed the longer term GEFS 6z mean starting to improve in the period between early / mid august!.. ☀️ .....august MAY redeem itself?...hang on, it’s July 23rd isn’t it..   my bad! ? 

19F80C00-5B2F-475A-8ADF-BC99AC613351.thumb.png.02087e74ad85ba16e915630c14e72d37.png667874CB-A0EA-475F-8875-B77D67837D25.thumb.png.4af47edf646fdba0d459a9d0f3801e6c.png0290CF56-8FD5-4FE3-8301-045310B41ABF.thumb.png.ae85d1e83f2dd79cbcdf720d3fb7d5cb.pngDDAC24C8-371F-4318-9CD0-11F084E2B1E2.thumb.png.86b292c3dba262d80ad1188e1d998eb7.png9C045B51-C4BD-4D83-AEA4-578253B44FD0.thumb.png.cf95226d7c8d7744998edd43593189a2.png897145E0-0AC8-4B3C-9B28-D16B7322F232.thumb.png.ffa6b4732a43a6b219429aadc6ca933b.png63349D4C-E646-4C8A-A4B9-B318B51264C2.thumb.png.40e8126563e35184ff1d150b6dc79c8c.pngDEDE9D3B-7AA2-4E75-9B97-3DCB34398F94.thumb.png.683a403e7a4dd3f8cbd3391f71782fac.png

Edited by Jon Snow
  • Like 6
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: chellaston, derby
  • Weather Preferences: The Actual Weather ..... not fantasy.
  • Location: chellaston, derby
1 hour ago, MATTWOLVES said:

26c and Sunny here...hazy but glorious... 

Yes that imagery is picking up on the High level cloud cover...the standard imagery is showing a sunny day for many,but that wouldn't be showing the very high level cloud cover...lovely here in Costa Del sedgley though

Most of the East Midlands and East Anglia are trapped under low grey north sea stratifiorm cloud. there appears to be an undercut of cool east,northeasterlies . This isnt high level cloud, but the dreaded north sea muck!

1 hour ago, MATTWOLVES said:

I don't dispute your takings on those noaa charts,but it still doesn't alter the fact that most data out to that point will be showing a slight bias towards climatology normal preferences.. Tamara points this out often as do senior met office operators! Any model data at this range can become very confused by misleading or overriding signals! If most of the data becomes clueless at longer range and reverts back to the default Weather pattern.. 8/9 times out of 10 it will be proven correct..

lol.. its posts like this that  are the reason i get called "defensive", because its  dismissive of the evidence presented. The charts i posted are not a "default" pattern, they pretty much bang on identified the exact pattern of ridging and troughing. If they did become confused and misleading of the overriding signals, whatever they are, then these charts wouldnt have the accuracy rate they do!

But instead of arguing about it, produce actual evidence, i did in support of the claims i make... prove to me through actual chart data that the NOAAs arent as good as i claim... which i underline are not gospel, but are 70-75% accurate for the timeframe they cover.

edit...heres one i prepared earlier lol
https://www.netweather.tv/forum/topic/95381-model-output-discussion-9th-april-onwards/page/52/?tab=comments#comment-4501442

Edited by mushymanrob
  • Like 4
Link to comment
Share on other sites

Posted
  • Location: Northern Ireland
  • Weather Preferences: Proper winter/Proper summer
  • Location: Northern Ireland
24 minutes ago, Jon Snow said:

Whilst I don’t pretend to be a forecaster..I don’t blog or anything like that, I’m just an enthusiastic amateur who loves the weather..  ...I have noticed the longer term GEFS 6z mean starting to improve in the period between early / mid august!.. ☀️ .....august MAY redeem itself?...hang on, it’s July 23rd isn’t it..   my bad! ? 

19F80C00-5B2F-475A-8ADF-BC99AC613351.thumb.png.02087e74ad85ba16e915630c14e72d37.png667874CB-A0EA-475F-8875-B77D67837D25.thumb.png.4af47edf646fdba0d459a9d0f3801e6c.png0290CF56-8FD5-4FE3-8301-045310B41ABF.thumb.png.ae85d1e83f2dd79cbcdf720d3fb7d5cb.pngDDAC24C8-371F-4318-9CD0-11F084E2B1E2.thumb.png.86b292c3dba262d80ad1188e1d998eb7.png9C045B51-C4BD-4D83-AEA4-578253B44FD0.thumb.png.cf95226d7c8d7744998edd43593189a2.png897145E0-0AC8-4B3C-9B28-D16B7322F232.thumb.png.ffa6b4732a43a6b219429aadc6ca933b.png63349D4C-E646-4C8A-A4B9-B318B51264C2.thumb.png.40e8126563e35184ff1d150b6dc79c8c.pngDEDE9D3B-7AA2-4E75-9B97-3DCB34398F94.thumb.png.683a403e7a4dd3f8cbd3391f71782fac.png

I am just like you. I hope August does redeem itself as this has been an epic summer in this part of the world. A decent August would put it up there with 2018 &!1983 though maybe not 1976!

Even the poor spells during this summer have been dry and grey.

 

  • Like 6
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
  • Location: Leeds/Bradford border, 185 metres above sea level, around 600 feet
2 hours ago, MATTWOLVES said:

I don't dispute your takings on those noaa charts,but it still doesn't alter the fact that most data out to that point will be showing a slight bias towards climatology normal preferences.. Tamara points this out often as do senior met office operators! Any model data at this range can become very confused by misleading or overriding signals! If most of the data becomes clueless at longer range and reverts back to the default Weather pattern.. 8/9 times out of 10 it will be proven correct..

Worth saying that the anomoly charts are not automated and can be clearly seen when reading the prognostic discussion. They are basically just global FAX charts so the human element will usually smooth out bias.

  • Like 7
Link to comment
Share on other sites

Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

Seeing a return of the Azores High feature more and more for the week after next in the GFS runs so far today.

While it’s a way out, it ties in well with a trend toward keeping the MJO more active right across the Pacific instead of stalling or decaying it over the western fringes.

With that comes a source of renewed positive frictional torques to initiate one last positive AAM cycle before the probable long-term slump setting in by around mid-August, with impacts on our weather soon after (cool & changeable tendency).

  • Like 6
Link to comment
Share on other sites

Posted
  • Location: Evesham/ Tewkesbury
  • Weather Preferences: Enjoy the weather, you can't take it with you 😎
  • Location: Evesham/ Tewkesbury

It's a case of anyone wanting a return to summer conditions very quickly better look away, this week's hot spell will seem a distant memory, turning cooler than average as well, anyway looking forward to the thundery breakdown overnight .....

ecmt850.240-9.png

h850t850eu-45.png

  • Like 4
Link to comment
Share on other sites

Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North

No comments on the ECM 12z operational?...I wonder why! ...anyway, yes it basically becomes more unsettled, trough dominated and cooler..think that just about covers it!   ? ☀️ ⛈ ...there’s even a rainbow....but no pot of gold at the end of it...

FA4152F4-7E23-4877-BBCE-93DD8D1171B1.thumb.png.cd8be7dfcec61cc13eacd8f7477528ca.pngA9A6192A-5B9E-4A0B-8807-4D4A0B8DA988.thumb.png.17b7fa6e7ffe8540cf14155e49348651.pngE61D9A1E-420A-4863-BE61-A37E06C79378.thumb.png.dbbe67222bc43e9b66f5d4c4e385ad85.png2CC3E246-0D6C-4C9E-A475-83824F3A76AF.thumb.png.94a94ed8c99245d995d8062df80ce1f8.png95BD6C58-276B-4271-AC25-A0AFCF529535.thumb.png.c2951f5d01940d4cc8c7994e3716d9e2.png4EE57C58-2AF1-4EAA-BEBB-A28D2FC70152.thumb.png.a218892b4508d9bd1146dc6599c28db5.pngD817A268-4700-4E8D-8D5C-840A364F82D2.thumb.png.941cb87fe553bd33f686d529e18fbbcc.pngAD5C5F50-FADB-47BE-8BF0-A59A4C9F2449.thumb.png.af34a0405018bd0f3ca0e271748f45fc.png

 

 

 

  • Like 5
Link to comment
Share on other sites

Posted
  • Location: East Ham, London
  • Location: East Ham, London
1 hour ago, Singularity said:

Seeing a return of the Azores High feature more and more for the week after next in the GFS runs so far today.

While it’s a way out, it ties in well with a trend toward keeping the MJO more active right across the Pacific instead of stalling or decaying it over the western fringes.

With that comes a source of renewed positive frictional torques to initiate one last positive AAM cycle before the probable long-term slump setting in by around mid-August, with impacts on our weather soon after (cool & changeable tendency).

To be honest, looking at the 12z output, it's hints more than anything else and it doesn't look anything more than a transient ridge.

We continue to struggle into August with the Azores HP held back by northern blocking and shallow troughs able to run ESE on a southerly-tracking jet across the British Isles. 

GEM continues to tease a mid-Atlantic ridge but that doesn't hold on the 12Z OP (JMA is similar).

In far FI, GFS OP tantalises while Control maintains the disappointing overall pattern.

Link to comment
Share on other sites

Posted
  • Location: Sedgley 175metres above sea level
  • Weather Preferences: Any kind of extremes. But the more snow the better.
  • Location: Sedgley 175metres above sea level
4 hours ago, mushymanrob said:

Most of the East Midlands and East Anglia are trapped under low grey north sea stratifiorm cloud. there appears to be an undercut of cool east,northeasterlies . This isnt high level cloud, but the dreaded north sea muck!

lol.. its posts like this that  are the reason i get called "defensive", because its  dismissive of the evidence presented. The charts i posted are not a "default" pattern, they pretty much bang on identified the exact pattern of ridging and troughing. If they did become confused and misleading of the overriding signals, whatever they are, then these charts wouldnt have the accuracy rate they do!

But instead of arguing about it, produce actual evidence, i did in support of the claims i make... prove to me through actual chart data that the NOAAs arent as good as i claim... which i underline are not gospel, but are 70-75% accurate for the timeframe they cover.

edit...heres one i prepared earlier lol
https://www.netweather.tv/forum/topic/95381-model-output-discussion-9th-april-onwards/page/52/?tab=comments#comment-4501442

You clearly have your methods and are simply in awe of those Noaa charts..I havnt got a problem with that. My main point was to say that from day 10 onwards all model output becomes fraught with error and the % scales decrease,regardless of the methods you use. There is not a method out there that can give you 70/80% success rate at nearly day 14. 3 or 4 days...perhaps! And I've had that drummed into me on numerous occasions!

Sorry to disagree with you on this...but that's Weather,and that's life.

  • Like 2
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)
34 minutes ago, stodge said:

To be honest, looking at the 12z output, it's hints more than anything else and it doesn't look anything more than a transient ridge.

We continue to struggle into August with the Azores HP held back by northern blocking and shallow troughs able to run ESE on a southerly-tracking jet across the British Isles. 

GEM continues to tease a mid-Atlantic ridge but that doesn't hold on the 12Z OP (JMA is similar).

In far FI, GFS OP tantalises while Control maintains the disappointing overall pattern.

We’re only at the start of the road modelling-wise. We have to look beyond what they show us at any one time, at even the most subtle trends.

I suspect it will be a few more days before we see anything more resounding... IF we do; I’m not saying it’s definite - but the chances are improving based on analysis of what drives the weather (which is not the models).

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: East Ham, London
  • Location: East Ham, London
28 minutes ago, Singularity said:

We’re only at the start of the road modelling-wise. We have to look beyond what they show us at any one time, at even the most subtle trends.

I suspect it will be a few more days before we see anything more resounding... IF we do; I’m not saying it’s definite - but the chances are improving based on analysis of what drives the weather (which is not the models).

I was discussing the Model Output Discussion as I do based on the charts I see and the trends I deduce from them. 

The 12Z GFS OP offers only a brief hint of rising pressure and the Control run doesn't even offer that. I've yet to see anything up to T+240 suggesting a return of settled and warmer conditions.

There may well be hints of something more settled for say, beyond mid-August, but I don't have access to that output (unless you count CFS and I doubt anyone takes that very seriously.

By the way, looks fine and frosty for Christmas Day:

image.thumb.png.d5eb8c24a5b14fe9e54d1521ef2177a8.png

  • Like 5
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Near Romford Essex.
  • Location: Near Romford Essex.
54 minutes ago, MATTWOLVES said:

You clearly have your methods and are simply in awe of those Noaa charts..I havnt got a problem with that. My main point was to say that from day 10 onwards all model output becomes fraught with error and the % scales decrease,regardless of the methods you use. There is not a method out there that can give you 70/80% success rate at nearly day 14. 3 or 4 days...perhaps! And I've had that drummed into me on numerous occasions!

Sorry to disagree with you on this...but that's Weather,and that's life.

Yeah, it's the same with using  Teleconnections  to try and see where things may be heading, problem with that methodology  is that there are too many variables, and how they interact, so a lot of guess work needed there.

Just look at what the models (all)  are showing in the near time period, and try to, if one is so inclined, guess their conclusion.

Link to comment
Share on other sites

Absolutely dreadful, this is going to be nothing other than painful. 

Almost exactly the same position we were in  late June when early July looked a write-off, and it was. While model output is never certain a major blocking pattern with an Azores, Greeny linkup isn’t something that’s going to go away anytime soon. 
 

2031826642_gfs-bournemouth-gb-505n32.thumb.jpeg.40473e63d9f48601831a99372407750b.jpeg

Link to comment
Share on other sites

Posted
  • Location: Castle Black, the Wall, the North
  • Weather Preferences: Spanish Plumes, Blizzards, Severe Frosts :-)
  • Location: Castle Black, the Wall, the North

There’s still very tentative signs from the GEFS 0z mean of an improving pattern in the run up to mid august as the Azores high / ridge starts to wax again?, but I stress, there are still plenty of very unsettled ensemble members during this period which is why I put emphasis on the word TENTATIVE!  

68B48D55-A270-4FA8-A9AB-9118AEEC221B.thumb.png.e877231b81d369bcea8a2f999684287f.pngC07C9CE4-A827-4388-928B-7DA76BB1EBEB.thumb.png.2b799e208f917337bd8daa165da63c95.png996372C9-9901-4844-80A5-6A6748391799.thumb.png.0c0a3cbc8c07f45dbd8e703bf8852e5f.pngE6C4C0B1-82FD-4341-9DCD-754CE6E39D1E.thumb.png.5028ad32e6a2d494a66ca27cef4653ea.pngB4993586-A045-4F33-B7D3-336EC4F72E52.thumb.png.7fe22cf9af8c2b2b37b917305e37f05c.png

 

Edited by Jon Snow
  • Like 8
Link to comment
Share on other sites

Posted
  • Location: st albans
  • Location: st albans

@mushymanrob I expect that some posters want accuracy and the NOAA output 8/14 (which is always the mean output from day11) simply won’t provide that. As you say, it generally gives a pretty good broad brush picture of how the upper pattern will look. However, getting the nuances like our approaching cut off upper trough into that just won’t show at 11 days out.  similarly, a transient ridge in a mobile flow won’t be there either. 
 

Nwp simply isn’t an exact science - however, output like noaa cpc is an excellent tool to use when making a judgement as to what conditions are likely to be most notable in week 2.  

  • Like 6
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: chellaston, derby
  • Weather Preferences: The Actual Weather ..... not fantasy.
  • Location: chellaston, derby
12 hours ago, MATTWOLVES said:

. There is not a method out there that can give you 70/80% success rate at nearly day 14. 3 or 4 days...perhaps!

 


Except that the research that firstly John did, and i subsequently did  suggests otherwise... maybe not at day 14, but the period where new patterns emerge , 7-11 days, then their accuracy rate is certainly 70% plus... Very rarely are they completely wrong, most of the time they are very close, quite often they are more or less bang on.
Ive been using them for 7/8 years now...2 publically, i simply wouldnt use them if they were as inaccurate as you suggest.

Its ok, they might not be everyones favoured source of data for whatever reason... but please dont dismiss the findings of those of us that do use them, and the evidence ive provided on many occassions.

9 minutes ago, bluearmy said:

@mushymanrob I expect that some posters want accuracy and the NOAA output 8/14 (which is always the mean output from day11) simply won’t provide that. As you say, it generally gives a pretty good broad brush picture of how the upper pattern will look. However, getting the nuances like our approaching cut off upper trough into that just won’t show at 11 days out.  similarly, a transient ridge in a mobile flow won’t be there either. 
 

Nwp simply isn’t an exact science - however, output like noaa cpc is an excellent tool to use when making a judgement as to what conditions are likely to be most notable in week 2.  

Accuracy or detail?... As you know, they are accurate in picking out the most likely pattern of ridging and troughing for the time period they cover, but dont/ cannot pick up on the nuances, the detail, so on that we agree. But by pattern matching them to the closest operational run, we CAN determine the detail better, thats the point... the ops hold the expected detail, so forecasting upto ten days ahead, possibly further, is something that can be done, and i do it.

Link to comment
Share on other sites

Posted
  • Location: st albans
  • Location: st albans
28 minutes ago, mushymanrob said:

Accuracy or detail?... As you know, they are accurate in picking out the most likely pattern of ridging and troughing for the time period they cover, but dont/ cannot pick up on the nuances, the detail, so on that we agree. But by pattern matching them to the closest operational run, we CAN determine the detail better, thats the point... the ops hold the expected detail, so forecasting upto ten days ahead, possibly further, is something that can be done, and i do it.

You can possibly dismiss a week 2 op evolution on the basis that it differs markedly from the cpc chart but only on the broad upper pattern for the day 10/12 period. I really wouldn’t be forecasting for day ten based on rough agreement between op and cpc. 

Link to comment
Share on other sites

Posted
  • Location: Ski Amade / Pongau Region. Somtimes Skipton UK
  • Weather Preferences: Northeasterly Blizzard and sub zero temperatures.
  • Location: Ski Amade / Pongau Region. Somtimes Skipton UK

I hope there is nothing definite about this long term chart from GFS. However some consistency in its runs showing a southerly tracking jet. This bodes for a period of unsettled conditions in August, especially in Southern Britain and the continent. Who would bet against early frost in Scotland ?

 C

GFSOPEU00_384_22.png

  • Like 6
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Broxbourne, Herts
  • Weather Preferences: Snow snow and snow
  • Location: Broxbourne, Herts
26 minutes ago, carinthian said:

I hope there is nothing definite about this long term chart from GFS. However some consistency in its runs showing a southerly tracking jet. This bodes for a period of unsettled conditions in August, especially in Southern Britain and the continent. Who would bet against early frost in Scotland ?

 C

GFSOPEU00_384_22.png

Did you ever find the source of the claim from sometime back that predicted a cool August for north west Europe?  Looks very close to the money judging by this!

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: chellaston, derby
  • Weather Preferences: The Actual Weather ..... not fantasy.
  • Location: chellaston, derby
50 minutes ago, bluearmy said:

You can possibly dismiss a week 2 op evolution on the basis that it differs markedly from the cpc chart but only on the broad upper pattern for the day 10/12 period. I really wouldn’t be forecasting for day ten based on rough agreement between op and cpc. 

That depends ....  for example last Saturday i posted about this next week

"We are expected to lose the high to our near North as that shallow trough in the Biscay area lifts out Northward and we pick up a mean upper flow just North of West - coupled with the Azores high ridging Northwards and a slight positive pressure anomaly over Greenland.
This suggests that after a breakdown next weekend we return to average summers weather. Unsettled and possibly a tad cooler than average with the usual mix of sunshine/showers/longer spells of rain. No disaster but nothing special"

That was based on the then  8 - 14 day NOAA chart.... id suggest that forecast is going to be proven to be pretty accurate, of course its never going to be spot on at that timeframe, but imho its close enough to be worth mentioning as its giving a pretty good idea of whats most likely.... with closer detail to be determined closer to the event. Im certainly happy with that level of accuracy, which is why i employ this method for my blogs.

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Ski Amade / Pongau Region. Somtimes Skipton UK
  • Weather Preferences: Northeasterly Blizzard and sub zero temperatures.
  • Location: Ski Amade / Pongau Region. Somtimes Skipton UK
6 minutes ago, Timmytour said:

Did you ever find the source of the claim from sometime back that predicted a cool August for north west Europe?  Looks very close to the money judging by this!

I think he is a forum member posting from Norway but cannot remember the name . Yes, seems likely to have called this right but still another week until August starts !

C

  • Like 1
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
  • UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-29 07:13:16 Valid: 29/03/2024 0600 - 30/03/2024 0600 THUNDERSTORM WATCH - FRI 29 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather

    Difficult travel conditions as the Easter break begins

    Low Nelson is throwing wind and rain at the UK before it impacts mainland Spain at Easter. Wild condtions in the English Channel, and more rain and lightning here on Thursday. Read the full update here

    Netweather forecasts
    Netweather forecasts
    Latest weather updates from Netweather

    UK Storm and Severe Convective Forecast

    UK Severe Convective & Storm Forecast - Issued 2024-03-28 09:16:06 Valid: 28/03/2024 0800 - 29/03/2024 0600 SEVERE THUNDERSTORM WATCH - THURS 28 MARCH 2024 Click here for the full forecast

    Nick F
    Nick F
    Latest weather updates from Netweather
×
×
  • Create New...