Model Output Discussion 18z 28/07/13

[Captain Shortwave]

And for those who say ecm is the superior model take a look at this:----  

Yeah the other models did so much better.....

They have all flip-flopped over the past week or so with the same low pressure system.

Edited September 6, 2013 by Captain shortwave

[ANYWEATHER]

it is superior. Statistically that cannot be argued. It beggars belief that people still post stuff like this.

 

Sure it has off days, but ALL the models have struggled recently. It's still the best and most likely to verify.

With Respect to you ,I don't think it is! Ecm is no better than the gfs, and why do folks get mad about someone posting a viewpoint about a computer model.

[Gaz1985]

it is superior. Statistically that cannot be argued. It beggars belief that people still post stuff like this.

 

Sure it has off days, but ALL the models have struggled recently. It's still the best and most likely to verify.

 

Actually I find the GFS to be quite accurate more especially with projected temperatures. ECM is good though in terms of projected pressure etc have to agree in that regard but wouldn't go as far as "superior"

Edited September 6, 2013 by Gaz1985

[Gaz1985]

It's very good to see the huge improvement in the Ecm 12z  tonight and it has a good chance of happening because there has also been a significant improvement in the GEFS mean as today has gone on, the 12z gefs is considerably more settled looking than the previous runs  so all we need now is the Ecm 12z ensemble mean to join the growing support for a much better outlook than how things looked first thing this morning, this is one of the reasons I love model watching so much, there are dramatic twists and turns, it's GREAT.

 

Long may it continue  I'm not ready for a heavy coat yet.

[Frank Trough]

With Respect to you ,I don't think it is! Ecm is no better than the gfs, and why do folks get mad about someone posting a viewpoint about a computer model.

 

i'm not mad, it's just you don't need to have a "feeling" or "preference" when there are mathematical, verification statistics available. I find it all a bit baffling, really.

 

Presumably (and i haven't researched this) the ECM sometimes verifies below other models (including the GFS) but the point is that it doesn't happen that often.

[ANYWEATHER]

Anyway. a cool autumn like forecast for the few days ahead, And next week looks decidedly autumn. Cool North Westerly winds. Best in the west!  

[Summer Sun]

Here is the latest from Gibby on the models

 

Good evening. Here is the report from the midday outputs of GFS, UKMO, GEM, NAVGEM and ECM for today Friday September 6th 2013.

 

The models tonight show the pendulum has swung back the other way from this morning's output with High pressure tonight showing a more dominant role again in the weather next week, albeit not in the best position for overly warm conditions. Before any ridge approaches from the West we have three or four days of unsettled and showery weather which only slowly leaves Easternmost Britain towards midweek.

 

GFS shows the ridge toppling SE over Britain midweek followed by a trough on Friday when some rain would be experienced by all for a time. High pressure then is shown to quickly re-establish itself for a time at the weekend before a more changeable pattern under the familiar North/South pattern develops in Week 2.

 

The GFS Ensembles show a fairly mundane pattern over the next few weeks with some rain in near average temperatures likely and temperatures gradually returning to the seasonal average. The operational was a strong warm outlier at one point in the second half of the run in the South.

 

The Jet Stream shows a sharp troughing over the UK currently which continues for a few days before the flow reverts to a position near Northern Scotland for the folloeing week with an unclear pattern thereafter.

 

UKMO tonight shows a ridge toppling SE over the UK towards midweek with a fine few days following the early week showers. A cold front is shown descending SE over the UK by Friday with some rain accompanying it.

 

GEM is much more High pressure based tonight with a ridge extending across Britain from midweek and just the briefest of interruption from weak fronts as they trundle SE with a little rain towards the end of the week. near normal temperatures seem likely.

 

NAVGEM tonight is opposed to it's own run of this morning with Low pressure hanging around SE England quite a while next week and drawing in reinforcements from the NW later with an unsettled end to the run for all with rain at times.

 

ECM tonight shows High pressure to the SW holding much more dominance in conditions over Southern Britain  later next week with a North/South split in the weather seeming likely. So after early week showers almost anywhere rainfall will gradually become confined to Northern areas later in the week with average temperatures for all and rather breezy conditions in the North.

 

In Summary the models continue to struggle with the course of events from the middle of next week. We have see-sawing model runs illustrating differences run to run and it is still very unclear as to whether later next week sees rain at times under the Atlantic Low influence or fine and drier conditions under a ridge from our own friend the Azores High.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

 

[johnholmes]

And for those who say ecm is the superior model take a look at this:----  

is it my old eyes or is that not a forecast for a week ahead, how the heck does anyone know which will be correct.

As to statistics Anyweather then best you take a look at them, it is not often that GFS, in the 500mb northern hemisphere checks, is not worse than ECMWF, link below, be it day 5 or day 6

as someone else has posted, of course it is less 'right' than GFS but not very often.

http://www.emc.ncep.noaa.gov/gmb/STATS/html/new_acz6.html

[Summer Sun]

I have a reply from Gibby re posting his model updates on here

 

I'm afraid it's unlikely I will be posting my analysis over on Netweather anytime soon. I will be posting on current weather events through the Winter Season on Netweather and TWO as and  when they happen in text format along with my new webcam links which now offer a live stream 24/7 looking WSW and ENE from my location. I found it too time consuming to post lengthy  analysis posts to multi forum platforms twice daily so thought I would give TWO the exclusivity on that as I joined their forum first.

Edited September 6, 2013 by Summer Sun

[ANYWEATHER]

is it my old eyes or is that not a forecast for a week ahead, how the heck does anyone know which will be correct.

As to statistics Anyweather then best you take a look at them, it is not often that GFS, in the 500mb northern hemisphere checks, is not worse than ECMWF, link below, be it day 5 or day 6

as someone else has posted, of course it is less 'right' than GFS but not very often.

http://www.emc.ncep.noaa.gov/gmb/STATS/html/new_acz6.html

Mr Holmes, I respect your knowledge ,But I think gfs and ecm have there problems But I Personally don't see that ecm is better

[Scorcher]

Dry but cool, not all that much has changed for most of the UK bar a little more sunshine and less likelyhood of showers.

 

 

Huge shift in my opinion, that persistent low to our east has gone in this run, in contrast to this morning's run. The uppers might be similar but not much else.

[ANYWEATHER]

I have a reply from Gibby re posting his model updates on here

Always thought that Gibby posted an amazing amount of information,!!! And I can believe he is tired of doing it!! 

[summer blizzard]

Huge shift in my opinion, that persistent low to our east has gone in this run, in contrast to this morning's run. The uppers might be similar but not much else.

 

Fair enough although i would urge caution since the jet profile of the ensembles is more in line with this mornings run.

 

[Yarmy]

The ECM and UKMO are objectively, indisputably better models than the GFS up to T144. 

 

 

Beyond that and they all fall off a cliff. This is done by measuring what they predicted against what happened: it is inarguable. Now it may be that for our small corner of the world the above figures don't hold, but I think that unlikely.  

Edited September 6, 2013 by Yarmy

[Frosty.]

Yes we have seen a significant improvement in the outlook tonight, this is reinforced by a very positive met office update today, it looks like we are in for a lot more summery weather in the next 2 or 3 weeks.

[mushymanrob]

I have a reply from Gibby re posting his model updates on here

 

thats odd.... once composed, which he does anyway, it only takes a couple of seconds to copy and paste ... im assuming thats what you do when posting his thoughts..

 

well the models all suggest what can only be discribed as 'normal' september weather... no extremes, just plenty of average, pleasant at times, abit wet at others, with the emphisis on drier and warmer IF the azores high ridges in.

[bluearmy]

thats odd.... once composed, which he does anyway, it only takes a couple of seconds to copy and paste ... im assuming thats what you do when posting his thoughts.. well the models all suggest what can only be discribed as 'normal' september weather... no extremes, just plenty of average, pleasant at times, abit wet at others, with the emphisis on drier and warmer IF the azores high ridges in.

Peehaps it has more to do with monitoring for replies and answering them. Martin woulnt just 'post and run'

[Frosty.]

I really like the Gfs 00z this morning, it shows a nice ridge of high pressure taking control from as early as tuesday with the residual remains of the shallow trough gradually shunted away southeastwards into mainland europe, increasingly fine weather spreads from the west with sunny spells and light winds with temperatures recovering and feeling pleasantly warm in the sunshine. By the end of next week the ridging is pushed further south as a sequence of vigorous depressions push eastwards from iceland and turns the weather a bit more unsettled across the north of the uk but pressure continues higher across southern britain throughout, as those lows push east, the azores/atlantic ridging across the south rolls with the punches and eventually this pays off because once the last vigorous low has gone, the azores/atlantic high builds in across the uk and brings a very settled spell of weather to the whole of the uk with lots of strong mid to late september sunshine and temperatures into the low 20's celsius but cool nights with fog patches.

[johnholmes]

post 6 days hence the anomaly charts give the flavour of what to expect, see below for the ECMWF-GFS output this morning which is similar to that from NOAA last evening

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

The upper ridge looks close enough to be  positive for the west but the trough may have as much influence for the east, at least at first in the 6-15 day time scale

[Summer Sun]

thats odd.... once composed, which he does anyway, it only takes a couple of seconds to copy and paste ... im assuming thats what you do when posting his thoughts..

 

well the models all suggest what can only be discribed as 'normal' september weather... no extremes, just plenty of average, pleasant at times, abit wet at others, with the emphisis on drier and warmer IF the azores high ridges in.

 

Yeah that's all needs to be done copy and paste then a link to the page on his site

 

Here is the latest from Gibby this morning

 

Hi everyone. Here is the morning look at the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Saturday September 7th 2013.

 

All models continue the basic pattern of high pressure to the SW and a West or NW flow over the UK in the coming week. The current shallow depression over NW Britain will simplify into a trough by Monday which crosses the UK with a cool and somewhat showery North flow in its wake down the East side of England dissipating by Wednesday. As mentioned High pressure to the SW will then dominate for the remainder of the week to varying degrees between the models. All show a West to NW flow with a mix between a North/South split pattern where the North sees the biggest share of rain bearing troughs crossing East and SE while ECM in particular brings that risk down into Southern areas too at times in temperatures close to average.

 

The Fax Charts show the complex and weak Low pressure areas around the UK simplifying to a main centre to the East of the UK by Monday and Tuesday with a cool North flow and rain near the east Coast. Elsewhere High pressure is shown to be nosing it's way into the UK from the SW in turn followed by a warm and moist SW flow reaching the NW around midweek.

 

GFS then brings a series of weak troughs across from the West next weekend and the start of the following week with some rain for all but probably not much in the South. High pressure then builds across the UK in the final third of the run with warm and sunny days alternating with cool, mist and potentially foggy nights.

 

The GFS Ensembles show a slow trend away from the cool uppers at present to levels more usual for September. There is occasional rain events sprinkled about throughout the output for almost all areas though much of it is small in amount or insignificant as High pressure remains not far away from the UK at times.

 

The Jet Stream shows a detached circulation cut off from the main flow around the UK for several days to come. The trend for the later part of the run sees the flow migrating further to the Northwest again indicative of GFS's show of High pressure close to Britain late in the run.

 

UKMO today shows a cold front sliding SE over Britain on Friday with a band of cloud and light rain on it. High pressure lies either side of this feature and as a result dry weather will soon follow the rain for the weekend.

 

GEM also shows a couple of weakish cold fronts sliding SE next weekend and beyond but with High pressure to the SW continuing to squeeze the life out of them and delivering no more than brief passages of light rain and drizzle as they pass between lengthy spells of fine and dry weather in between.

 

NAVGEM shows slightly more potency to the Atlantic West or NW feed next weekend as a cold front brings some rain SE across all areas. A cool and potentially showery NW airflow is then shown to end the run.

 

ECM today shows an unstable NW feed across the UK by the end of next week and the weekend with  weak trough clearing the South with a little rain followed by a strengthening and cool NW flow with rain at times principally in the North but extending down to the South at times too. 

 

In Summary today there is still a lot of uncertainty between the detail of events from the middle of next week. though the theme of high pressure to the SW is a popular theme this morning the detail on how much it will affect the UK weather late in the week and beyond is still open for debate. GFS goes all out in bringing High pressure back over the UK late in it's run though it was a warm outlier later on. UKMO and GEM are in the middle ground this morning offering a few weak fronts crossing East over Britain with a lot of dry weather in between and at the other end of the scale we have NAVGEM and ECM who bring a steadily more potent feed of NW wind and rain at times, possibly for all by 10 days time. This story has a few days to run yet I feel until the exact route and path of the current showery Low pressure on its exit route out of the UK is known for definite.

 

http://www.norton-radstockweather.co.uk/Model-Analysis%282859336%29.htm

[Summer Sun]

After a wobble for a few days UKMO once again back to high pressure rebuilding next week

 

UKMO

 

 

ECM isn't as keen as UKMO is at t144 though

 

 

Nor is GFS

 

 

So at the moment its UKMO v ECM and GFS at t144

Edited September 7, 2013 by Summer Sun

[Frosty.]

The GEFS 00z control run brings another taste of summery weather throughout the second half of september with high pressure becoming dominant with temperatures comfortably into the low 20's celsius with lots of sunshine and light winds but cool nights with fog patches, you could call it last of the summer wine.

[bluearmy]

After a wobble for a few days UKMO once again back to high pressure rebuilding next week

 

UKMO

 

ECM isn't as keen as UKMO is at t144 though

 

 

 

Nor is GFS

 

 

 

So at the moment its UKMO v ECM and GFS at t144

 

it seems the direction of energy wrt to the next trough is the next conundrum for the nwp to resolve.  gem was the first model to bring it nw/se and that has become a plausible option.  experience of the past few troughs would make me think that ukmo is a better bet but as the wavelengths change, maybe we will see the repeating pattern undergo some changes in energy distribution. certainly the period beyond mid month continues to see extended ens supporting a rise in heights.before that, the mid month deep depression off n scotland is appearing with alarming regularity in the ens (both ecm and gefs).

[Frosty.]

As with the Gfs 00z op and GEFS 00z control run, the GEFS 00z mean shows high pressure winning out from mid month onwards with increasingly benign, settled and warm weather with long sunny spells and light winds with temperatures into the low 20's celsius bringing a nationwide taste of summer but since it's autumn, overnight it would turn rather chilly with fog forming. It's not a smooth transition to settled weather, the azores/atlantic high has to roll with the punches for a while as unsettled weather sweeps across more northern parts of the uk but when the high gets it's chance, it takes it big time, let's hope this trend continues and we have a golden spell of weather through the second half of the month and possibly into early october.

[joggs]

A quickie,have not got time(and on mobile) what are the models showing re nxt wkend? Im running great north run and dont want it scorchio!!!.Much appreciated.