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Model output discussion - into July 2020


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...Like shoals of fish they are starting to point the other way in midstream...ūüĎł Recent NWP, up to the start of this week, had seemed¬†suspicious¬†the way it had reverted to extrapolating the defaul

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Posted
  • Location: Salwick Lancashire +0.000000002 ASL
  • Weather Preferences: Horizontal Drizzle
  • Location: Salwick Lancashire +0.000000002 ASL
    14 hours ago, northwestsnow said:

    EC pretty consistent with a NW SE split next week.

     

    Aaaaand what do we get in the Northwest? ?

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    Posted
  • Location: County end Oldham 202 m Above sea level
  • Location: County end Oldham 202 m Above sea level
    16 minutes ago, Iceaxecrampon said:

    Aaaaand what do we get in the Northwest? ?

    It's been rubbish the past week, no escaping that.

    The drier days will hopefully begin to increase next week,Inc our patch.

     

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    Posted
  • Location: Crymych, Pembrokeshire. 150m asl
  • Weather Preferences: Extremes of all kinds...
  • Location: Crymych, Pembrokeshire. 150m asl

    Desperately trying to find some positive signs in the reliable range but nothing much on offer I'm afraid..... 

    These charts from +144 (9th July) don't really bring summer back :

                                             500s                                                        850s

    ECM       1383073118_ECM1-144500.thumb.gif.74a001755067e6d8cdea55214856e40e.gif  1779523919_ECM0-144850.thumb.gif.2eb0fb8d29ad933e2817667a4c82e0d0.gif

    UKMO   268702092_UKMO144-500.thumb.gif.39e109d94fe4f544bc3a1096a296158d.gif   1242552579_UKMO144-850.thumb.gif.f29cfa9a331d5504e2d6e8fd0c43e6e7.gif

    GFS      73542293_gfs-0-144500.thumb.png.12a07a4bae83669dbc2b7ed037ee9c51.png   1779417186_gfs-144850.thumb.png.6b94a61defc5178cbb06e128f600c0dc.png

    GEM     1210972704_gem-144500.thumb.png.fb59c76d06d86ebc90049981c54ab41e.png   1647544942_gem-144850.thumb.png.f0967066624d28f403808c7b47213ae8.png

    There is some hope in the fact that these charts do not share much agreement, except perhaps for the rough position of the Azores high (not difficult to forecast, really) so perhaps they could all be wrong....

    Here is the ECM 500hPa anomaly GIF for the next days.  Doesn't look too favourable for a settled July at least in the next 10 days....

    ECM_anomalies.thumb.gif.6393bfafbab8a68d616e19111fabaa8a.gif

     

    Edited by Sky Full
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    Big improvement south of the m4 next week - looks really good but elsewhere will have to wait until around the 10th of July. The high looks pretty robust in its ridging and not too reliant on any shortwaves so I think this will come off. I always say that the stronger the high is modelled, the more likely it is to come off.

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    Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth

    ECM clusters again only have one solution after D7, not particularly helpful. So I scrolled through all 51 ensembles for D13/D14 :). My personal summary of the ensembles: There will be weak ridges to the SW and to the NE. There will be an attempt at a link-up of the two. However, a trough will either try to drop in a NW-SE direction through the UK, or a trough will develop in situ to our SE. The interplay between the ridges and troughs is extremely unclear. Many ensembles plonk the trough over the UK with link-up between the ridges going north of us - not summery for the UK. However, very close behind are the number of ensembles that manage to link the ridges via the UK (a bit like some of the ECM46 charts have suggested recently) with the trough blocked out to the NW - this would be game on for UK summer. A smaller grouping push the ridge further south creating a NW/SE split for the UK. 

    It was quite a relief to look more closely at the individual ensembles, as yesterday's clusters painted a far bleaker picture that suggested the UK trough idea for mid-July was way out in front, whereas I would say it is only slightly ahead of the UK high grouping.

    Also, I had been a little critical of how the clusters had handled next week, but I did a quick check on how they are progressing and maybe I've been a bit unfair. Below I'm posting the T144 chart from this morning's clusters (9th July), and comparing how this date was predicted at T312, T288, T264 and T240. Aside T312, I can't argue too much with how they picked up the pattern, just not quite seeing the trough to the north as strongly as it is now likely to be (which often happens).

    The latest clusters for 9th July

    ec-ens_nat_z500scenarios_2020070300_144.

    and how the clusters predicted the 9th of July between T312 and T240

    ec-ens_nat_z500scenarios_2020062600_312.

    ec-ens_nat_z500scenarios_2020062700_288.

    ec-ens_nat_z500scenarios_2020062800_264.

    ec-ens_nat_z500scenarios_2020062900_240.

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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

    The next 24-36 hours should provide enough interest for any weather enthusiast!

    The wave out in the Atlantic is in s developing upper air pattern and seems set to deepen as it approaches Ireland, perhaps Ulster really and then moving quickly into the N Sea, track dependent on how much it deepens. Yet again more very strong winds on its southern flank, probably gales; off to have a look at how UK Met is dealing with it

     

    Comparing GFS 06Z to its 00Z run the 06 looks a lot nearer the idea UK Met have if you look at their Fax charts. Just noticed they have recently it seems issued wind warnings for the central belt of the UK and specifically mention east of the Pennines for wind strengths.

    Edited by johnholmes
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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

    On to further ahead and to me there is little chance in the next 6-10 days, if not longer, for any settled spell. Check the 500 mb predicted charts. Until they show some indication of less speed at 500 mb then, as one or two have commented regarding the temperature contrasts in eastern n America, will continue to feed disturbed weather across the Atlantic at the UK.

    So close in and further our plenty of weather interest but not what many of us would prefer=settled, dry warmth and less damn wind. More like autumn with the fairly frequent wind speeds around here.

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    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Anything out of the ordinary!
  • Location: Cambridge, UK
    4 minutes ago, johnholmes said:

    On to further ahead and to me there is little chance in the next 6-10 days, if not longer, for any settled spell. Check the 500 mb predicted charts. Until they show some indication of less speed at 500 mb then, as one or two have commented regarding the temperature contrasts in eastern n America, will continue to feed disturbed weather across the Atlantic at the UK.

    So close in and further our plenty of weather interest but not what many of us would prefer=settled, dry warmth and less damn wind. More like autumn with the fairly frequent wind speeds around here.


    096004A8-3E7A-4477-81F2-C432751F62CE.thumb.gif.daa65e4f7d368e56cf5458fb1527f18d.gif

    Not a good chart for decent UK summer weather really. The odd better day here and there, but disappointing more often than not.

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

    O k..hand on heart, the GEFS 6z is mixed, to say the least..and yet..the ingredients are still there for some better times ahead at some point this month..wouldn’t be difficult to achieve that would it?!!!!?..cherries included ? 

    ps..as for the 500 mb..always sceptical about fine spells, no change there then!?

    C9A50522-65E8-4161-A778-BE5CE6C07F85.thumb.png.3e8bae698f111cdda0d4fce4d3794ee5.png62D3EA4A-CDB0-4D5D-8B9B-D3C61B5A4F32.thumb.png.95afa220c2ec965d06f1e0715e009844.png32FCFF31-A261-4B81-BD27-5AC44DD0F694.thumb.png.9f2fbec479358359079220e904ecd280.png4F93F72D-5CF0-4491-9D24-82031FE077EB.thumb.png.dc15846fee2f4b82e328b2379fef8ace.png239082A2-CC74-4BCE-9CCA-37C55CAF6470.thumb.png.2491764d7760cd04aacf7eb8c1ea8de2.png

    Edited by JON SNOW
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    Posted
  • Location: Sible Hedingham, North Essex
  • Location: Sible Hedingham, North Essex

    So a few questions:

    Was the AAM forecast wrong?

    Are we confident in the Met Office extended forecast (I’m not !)

     

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    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Anything out of the ordinary!
  • Location: Cambridge, UK
    3 minutes ago, Djdazzle said:

    So a few questions:

    Was the AAM forecast wrong?

    Are we confident in the Met Office extended forecast (I’m not !)

     

    AAM isn’t a guarantee of any type of weather, like the MJO isn’t....it’s just a guide to a likelihood of conditions. You’d expect less settled than more settled weather under a -AAM regime in the UK, but it doesn’t automatically consign it to the dustbin. We could hang on to enough ridging to make it pleasant enough.

    Im also not confident in the Met forecast at the moment, but would happily be proved wrong!

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    Posted
  • Location: Sedgley 225metres above sea level
  • Weather Preferences: Summer heatwaves and electrical storms, and fidgid Arctic type winters
  • Location: Sedgley 225metres above sea level

    The ECM mean is favourable out to mid month but tends to drop away again towards day 14..1014mb as an average for the mean. After speaking with one of our knowledgeable posters earlier it would be interesting to know what signals are currently leading the EC46, because it seems to be in know rush to change the overall pattern. This I Completely agree with. I've noticed some are doubting the Mets thoughts also moving forward... Perhaps Glosea is seeing a more positive trend than some of the other Long Range Models! Will be interesting to see if there update is the same as the last few days, or if its changed somewhat after last night's poor EC. 

    Edit.. I'm with you @JON SNOW on those 500mb charts, they never seem to highlight any real improvement in conditions, its like viewing the 46 at times, where no change ever seems to be fourth coming. 

    Edited by MATT‚ėÄÔłŹ
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    Posted
  • Location: Cambridge, UK
  • Weather Preferences: Anything out of the ordinary!
  • Location: Cambridge, UK
    12 minutes ago, MATT‚ėÄÔłŹ said:

    The ECM mean is favourable out to mid month but tends to drop away again towards day 14..1014mb as an average for the mean. After speaking with one of our knowledgeable posters earlier it would be interesting to know what signals are currently leading the EC46, because it seems to be in know rush to change the overall pattern. This I Completely agree with. I've noticed some are doubting the Mets thoughts also moving forward... Perhaps Glosea is seeing a more positive trend than some of the other Long Range Models! Will be interesting to see if there update is the same as the last few days, or if its changed somewhat after last night's poor EC. 

    Edit.. I'm with you @JON SNOW on those 500mb charts, they never seem to highlight any real improvement in conditions, its like viewing the 46 at times, where no change ever seems to be fourth coming. 

    That isn’t true....

    4E9D285B-F4C2-4C4C-9398-AC167A80E959.thumb.gif.54a546442cd12ef69ca5ba47b430d91a.gif

    Look at this archived 500mb plot back from the middle of the very settled May we just had. Marked troughing out in the Atlantic and upper and surface ridging over the UK - equals fine, dry and settled at the surface, which is exactly what transpired. If the flow is flat as is currently shown, you just won’t get that sort of lasting settled weather here. Simple as that! ?

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    Posted
  • Location: Sedgley 225metres above sea level
  • Weather Preferences: Summer heatwaves and electrical storms, and fidgid Arctic type winters
  • Location: Sedgley 225metres above sea level
    9 minutes ago, mb018538 said:

    That isn’t true....

    4E9D285B-F4C2-4C4C-9398-AC167A80E959.thumb.gif.54a546442cd12ef69ca5ba47b430d91a.gif

    Look at this archived 500mb plot back from the middle of the very settled May we just had. Marked troughing out in the Atlantic and upper and surface ridging over the UK - equals fine, dry and settled at the surface, which is exactly what transpired. If the flow is flat as is currently shown, you just won’t get that sort of lasting settled weather here. Simple as that! ?

    It just seems like ages when someone posted these charts showing decent conditions. On the other hand it may be due to the fact its been ages  since we actually had decent conditions.. ?

    Edited by MATT‚ėÄÔłŹ
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    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
    1 hour ago, Djdazzle said:

    So a few questions:

    Was the AAM forecast wrong?

    Are we confident in the Met Office extended forecast (I’m not !)

     

    Only the CFS was wrong, the Euro absolutely crushed it on -AAM.

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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

    re this

    The ECM mean is favourable out to mid month but tends to drop away again towards day 14..1014mb as an average for the mean. After speaking with one of our knowledgeable posters earlier it would be interesting to know what signals are currently leading the EC46, because it seems to be in know rush to change the overall pattern. This I Completely agree with. I've noticed some are doubting the Mets thoughts also moving forward... Perhaps Glosea is seeing a more positive trend than some of the other Long Range Models! Will be interesting to see if there update is the same as the last few days, or if its changed somewhat after last night's poor EC. 

    Edit.. I'm with you @JON SNOW on those 500mb charts, they never seem to highlight any real improvement in conditions, its like viewing the 46 at times, where no change ever seems to be fourth coming. 

    I am very happy to chat via pm and explain these charts and give proof that, used carefully, they are the best short-mid term charts we have access to for giving a good guide to what weather to expect 6-10 days and sometimes out to 14 days down the line.

    Just pm me if you are interested

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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks
    1 hour ago, mb018538 said:

    That isn’t true....

    4E9D285B-F4C2-4C4C-9398-AC167A80E959.thumb.gif.54a546442cd12ef69ca5ba47b430d91a.gif

    Look at this archived 500mb plot back from the middle of the very settled May we just had. Marked troughing out in the Atlantic and upper and surface ridging over the UK - equals fine, dry and settled at the surface, which is exactly what transpired. If the flow is flat as is currently shown, you just won’t get that sort of lasting settled weather here. Simple as that! ?

    very true mb

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    Posted
  • Location: Carryduff, County Down 420ft ASL
  • Location: Carryduff, County Down 420ft ASL
    3 hours ago, Djdazzle said:

    So a few questions:

    Was the AAM forecast wrong?

    Are we confident in the Met Office extended forecast (I’m not !)

     

    If it says warm and dry, no i'm not confident. If it says below average and wet, then yes I am 

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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    Thank goodness there'll be a fresh breeze on Saturday night, as it'll be a muggy one!?

    h500slp.png    h850t850eu.png

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    Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth

    I think we need to be extra cautious at the moment about the D8-D15 period. The mean anomalies are small. But that does not necessarily tell us the mean charts are representative of the ensembles, as some can be at one extreme, others at a different extreme, and the mean simply cancels them out. 

    This is EXACTLY the case for today's ECM 00Z ensembles if one checks them out; this is the ECM control run at D14, for instance: https://weather.us/model-charts/euro/europe/m0_sea-level-pressure/20200717-0600z.html, and here is a completely opposite member https://weather.us/model-charts/euro/europe/m5_sea-level-pressure/20200717-0600z.html - these two members are representative of a large number of the ensembles, you can see them all by selecting "Switch Members" from the box on the left).

    When there is a very strong signal in the mean chart, it is easier to be more certain about which way most of the ensembles point - as to get a large anomaly, you need most of the ensembles to resemble that anomaly in some way.

    A lack of strong mean signals can either mean the ensembles collectively are close to the seasonal norm, or they are cancelling opposing signals out. We don't know just from looking at the summary mean.

    Yes, of course, it is often the case that a split in the ensembles eventually leads to a fudge of the split, and therefore something close to the mean, but even so, that is not the same as trying to decipher what the models are saying right now.

    So my view of the mean charts for mid-month, in this instance, is that they don't tell us the most likely way forward - instead, they tell us that the overall direction of travel is a lot further from being resolved than usual. All options are on the table from best to worst!!

     

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    Posted
  • Location: Bedfordshire
  • Weather Preferences: Thunderstorms, warm/hot plumes, snow, anything severe
  • Location: Bedfordshire

    Look what the CFSv2 is showing for week 2... looks like a blocking if I'm correct? ?

    wk1.wk2_20200702_z500.thumb.png.b412bcf9082458fc75f064952d5853fd.png

    Meanwhile, the 12z ICON has just rolled out, and it's showing the warmer and more settled conditions to be confined to the south

    anim_kar6.thumb.gif.e33c2b2af534375168469d66a93bea19.gif

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    Posted
  • Location: Bournemouth
  • Weather Preferences: Hot, Very Warm, Warm! Sunshine & TS
  • Location: Bournemouth
    3 minutes ago, Man With Beard said:

    I think we need to be extra cautious at the moment about the D8-D15 period. The mean anomalies are small. But that does not necessarily tell us the mean charts are representative of the ensembles, as some can be at one extreme, others at a different extreme, and the mean simply cancels them out. 

    This is EXACTLY the case for today's ECM 00Z ensembles if one checks them out; this is the ECM control run at D14, for instance: https://weather.us/model-charts/euro/europe/m0_sea-level-pressure/20200717-0600z.html, and here is a completely opposite member https://weather.us/model-charts/euro/europe/m5_sea-level-pressure/20200717-0600z.html - these two members are representative of a large number of the ensembles, you can see them all by selecting "Switch Members" from the box on the left).

    When there is a very strong signal in the mean chart, it is easier to be more certain about which way most of the ensembles point - as to get a large anomaly, you need most of the ensembles to resemble that anomaly in some way.

    A lack of strong mean signals can either mean the ensembles collectively are close to the seasonal norm, or they are cancelling opposing signals out. We don't know just from looking at the summary mean.

    Yes, of course, it is often the case that a split in the ensembles eventually leads to a fudge of the split, and therefore something close to the mean, but even so, that is not the same as trying to decipher what the models are saying right now.

    So my view of the mean charts for mid-month, in this instance, is that they don't tell us the most likely way forward - instead, they tell us that the overall direction of travel is a lot further from being resolved than usual. All options are on the table from best to worst!!

     

    I completely agree with this, I've said a few times now post decent consensus at short range nearly all the models and all their respective ensemble packs have generally had a wide scatter on them, it renders the mean almost as ineffective as picking a single ensemble and by default you nearly always end up with some form of ridging from the south west - how many beyond 6-7days in the past month has the mean not shown a weak azores high ridging in? Clusters are a better indicator I feel. 

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