Model Output Discussion 12hrs. 01/10/13

[BlueHedgehog074]

Doesn't clearly look like the ECMWF wants to be friends with the UKMO model tonight. From up to the 144 hour period at least, it's turning out to be a battle now of: GFS / ECMWF vs. UKMO / CFS / NAVGEM - 3 against 2, who will win? Will the Southerly airflow setups of the GFS / ECMWF be correct, or has the other 3 models, with their Northerly-like setups, got this one nailed? Find out in future model updates.

 

It will be amusing, however, to see which side the 12Z JMA model takes tonight.

 

[Captain Shortwave]

Well the good new for people who don't like high pressure is that the the Atlantic might get in by day 9

 

Trouble is the chart is an almost exact replica of what we are currently experiencing. The the Azores high would probably build straight back in.

Or the ECM could just struggle to get the low through whatsoever

^JMA shows raging zonality, no I'm not joking  

Edited October 4, 2013 by Captain shortwave

[Cloud 10]

Doesn't clearly look like the ECMWF wants to be friends with the UKMO model tonight. From up to the 144 hour period at least, it's turning out to be a battle now of: GFS / ECMWF vs. UKMO / CFS / NAVGEM - 3 against 2, who will win? Will the Southerly airflow setups of the GFS / ECMWF be correct, or has the other 3 models, with their Northerly-like setups, got this one nailed? Find out in future model updates.

 

It will be amusing, however, to see which side the 12Z JMA model takes tonight.

 

 

None of the above!

 

[smithyweather]

The good thing is that we are finally seeing signs of a breakdown. Where as a few weeks ago there were no signs of this.

[BlueHedgehog074]

None of the above!

 

J144-21.gif

Probably will end up being one for the trash can, though has now resulted a 3 way battle (he hee): GFS /ECMWF vs. GFS / CFS / NAVGEM vs. JMA.

[Summer Sun]

More unsettled tonight from ECM to end its run but we get 6 or 7 days of settled weather depending how far east you are

 

t192 onwards shows the Atlantic pushing the high eastwards slowly

 

 

It remains mild though

 

 

Just a reminder of the ensemble mean for the latter stages of ECM this morning

 

 

The 12z ensemble run at around 21:30 will be interesting will it back the Op in bringing the low in or will it persist with the high

[No Balls Like Snow Balls]

IMO the HP doesn't look to have as much of a grip over the UK on this evenings runs.

 

ECM big HP out West ready to push HP out the way

 

 

GEFS ensemble mean HP well on its way to losing its grip.

 

 

ooppps posted wrong chart. doh

 

 

 

 

 

 

 

Edited October 4, 2013 by No Balls Like Snow Balls

[Summer Sun]

Latest from Gibby

 

Good evening. Here is the report on the 12 noon outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Friday October 4th 2013.All models support rising pressure across the UK but especially over the South where High pressure edges up into Southern Britain later in the weekend. Northern areas will stay breezier with a weakening cold front moving SE across Scotland and Northern Ireland and reaching as far as Northwest England and Wales before losing it's identity by Monday. It's at that point when the models differ in the way they interpret High pressure with regard to positioning next week.

 

GFS shows High pressure moving over the UK and away East later next week with a freshening Southerly wind and troughs bringing some rain East into the UK later in the week. It would again feel rather warm in any brighter spells with a very limited risk of fog for a time early in the week. Then through the extended part of the run the weather becomes more mobile as a train of deep Atlantic Lows cross NE to the NW of Britain with cloudy and windy weather with occasional rain for all areas but always heaviest to the NW.

 

UKMO has an alternative way of handling High pressure next week with the main centre transferring to a position to the NW of Britain by midweek. A cold front would sink South across all areas later in the week with rather cool conditions developing especially at night with some ground frost possible in the North and fog more extensively across many areas at times by night and morning, especially later next week.

 

GEM alternatively shows High pressure slipping away SE next week with a SW flow developing over many parts especially towards the NW where troughs moving NE would deliver rain at times through the weekend and start to the second week.

 

NAVGEM uses the Northern route for High pressure, positioning it to the North of Scotland by midweek before it slides slowly SE down the North Sea all the while maintaining dry and fine conditions for many with the risk of mist and fog night and morning with dry and bright days.

 

ECM is keener on removing High pressure away East later next week at the expense of Low pressure edging in off the Atlantic spawning a period of warm and moist Southerly winds again ahead of potentially quite heavy rain followed by a showery weekend especially in the South.

 

The GFS Ensembles show a more unsettled second half of output tonight than was shown this morning and this is supported by some other outputs from GEM and ECM. Temperature wise continues to look milder than average with surface winds maintained from a warm source and supported by 850 uppers above average for October.

 

The Jet Stream shows the flow relocating to the NW of Britain this weekend and much of next week before it gradually descends back South to be flowing West to East across the British Isles by the second half of the run.

 

In Summary there is a bit of movement towards a more unsettled end to next week and beyond from this evening's output. The programmed High is still on course to affect all areas at some point next week and for much of the week in the South with dry and fine conditions with mist and fog problems night and morning. There are stronger signals though for Low pressure to edge in from the Atlantic from the NW or West late next week and onward with some rain at times, possible heavy in mild and humid conditions.

 

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

[ANYWEATHER]

The Rollercoaster of model watching carries on and we are not anywhere near Winter yet! The gfs  and ecm look strangely in agreement tonight with a breakdown in the weather this time next week....A far cry just from yesterdays output,,,But it will be interesting where tomorrows output takes us, but with the evolution tonight looks realistic, But Im looking forward to some really nice Autumn weather in the week ahead, and hopefully the Atlantic will be delayed!  

[Frosty.]

Fantastic Ecm 12z tonight, it shows a very warm spell through most of next week with temperatures in the south of the uk in the 22-24c range, this is not unrealistic because it reached 22c in the southeast today and the synoptics are currently nothing like as good as the ecm shows next week. So, a warm and settled spell trending very warm and increasingly humid, maybe a thundery breakdown to end next week and then a reboot of the fine pattern in my opinion by T+240 hours, another warm settled spell after an unsettled blip?..maybe  we will keep seeing a rinse and repeat pattern until sometime in november. Enjoy the summery weather, it looks like being warm enough for a few BBQ's next week...cheers

[Summer Sun]

ECM ensemble following the 00z with high pressure lasting longer than the Op is suggesting

 

 

[Frosty.]

Wow what a peach of an Ecm 12z ensemble mean, totally in line with the majority of the output today..October BBQ anyone? :- ) BRING IT ON

[Downburst]

Wow what a peach of an Ecm 12z ensemble mean, totally in line with the majority of the output today..October BBQ anyone? :- ) BRING IT ON

The 500mb charts though in fairness, the mean too, not the operational. I reckon the GFS 12z Op run is spot on, surface low over us by Wednesday.

[phil nw.]

Wow what a peach of an Ecm 12z ensemble mean, totally in line with the majority of the output today..October BBQ anyone? :- ) BRING IT ON

Tonights CPC 8-14 day hts. forecast would support the ongoing Euro.block too Frosty.

 

 

London ens graph suggest a lot of dry weather with high teens max 's in the coming week.

 

Although 12z UK run seems out of sync.with other outputs,they all suggest that the far north and north west of the UK could be more unsettled from time to time as Atlantic fronts move over the top of the high on occasion.

No real sign yet though of a full on Atlantic onslaught it must be said.

Edited October 4, 2013 by phil nw.

[Iceni]

Fantastic Ecm 12z tonight, it shows a very warm spell through most of next week with temperatures in the south of the uk in the 22-24c range, this is not unrealistic because it reached 22c in the southeast today and the synoptics are currently nothing like as good as the ecm shows next week. So, a warm and settled spell trending very warm and increasingly humid, maybe a thundery breakdown to end next week and then a reboot of the fine pattern in my opinion by T+240 hours, another warm settled spell after an unsettled blip?..maybe  we will keep seeing a rinse and repeat pattern until sometime in november. Enjoy the summery weather, it looks like being warm enough for a few BBQ's next week...cheers

 

 

I can live with that. I have this 'weather balancing itself' theory - if it's warm and dry for a few weeks or a month, it'll switch to the opposite for a few weeks or a month - which would make for a nice cold and frosty November or December. It's rubbish, but seems to work out quite often. Shoot me down in flames...

[lorenzo]

Interesting comparison at 144 hrs between the UKMO 00z and the GFS 12z.

 

gfs 12z..gfs-0-144.png  ukmo 00z..UW144-21.gif

 

 

Unusual to see such massive differences at that timescale.

 

Almost certainly MJO related given the difference in projection from these 2 models, UKMO very progressive here..

 

UKMO also has support (for what it's worth) from the latest CFS run.

 

UKMO...

 

CFS...

 

As u can see, very identical. Will be an interesting ECM coming up...

 

SE Blizzards

 

Here is a plot of ensembles derived from CFS input which can account for some of the similarity here.

http://www.kylemacritchie.com/real-time-maps/realtime-mjo/

 

Cannot verify with real time info. due to US shutdown. But a pretty good balanced forecast based on what the main models have delivered this week. Some analogs are in the Tech thread for base patterns. Good to see some form of disagreement at the very least gives us something to debate around. ( awaits pub run ensembles for nonsense..)

[Tamara]

This thread is the MOD thread, but it is well known as one that oscillates in line and mood with every model output and associated ensemble suite, rather than any wait and see philosophy which can show that intra day variations are, just that..variations..of which any one (apparent) agreed solution can still prove wrong .

 

The retrogressive northerly of the UKMO (toned down already by the model itself) remains the unlikely solution as mentioned this morning, and sure enough tonights EPS ensemble suite reflects that much more than the member suite posted this morning with  fewer members supporting it - but the point here, and one which is often repeated but still gets lost is the fact that even individual whole suites can have an (apparent) consensus blend to any one outcome that can be turned around 12 to 24 hours later, and sometimes longer. So, with that in mind, here are tonights individual member ensemble maps which generally support the flatter less amplified pattern with the jet stream across to the north more than this morning, and depict a more round/oval anticyclone orientation as mentioned earlier, with only a very small minority supporting the UKMO amplified solution with us on the 'polar' side of the jetstream

 

 

However, no model (like the UKMO f.e atm) repeats its output for nothing, so even though its suggestion appears an increasing minority - every possibility has to be taken into account..irrespective of the popular theme of what is hoped for on the MOD thread

 

Preferences do not equate to computer model verification - and the weather we want at our own surface level is not satisfied, solved or sated on any intra day basis through the computer models themselves  Such expectations lend themselves to disappointment (firstly) but also, ocasionally surprise when such preferences are suspended.

 

Such is the nature when human emotions and wishes get involved with data number and paper crunching computer models

[SMU]

A sudden change expected tonight & overnight on the models....

 

S

[Cloud 10]

The plot thickens.......latest 120hrs fax chart backs the UKMO raw output.

 

[SMU]

The GFS 18z has sniffed a bit of the UKMO coffee & has totally morphed towards the UKMO @ 96-

 

Probably not quite get there this run.... -  But watch the GFS ensembles collapse over the next 24-48 hours -

 

Were not saying anything mega cold - however there is night & day difference between the ECM/ GFS solution & the UKMO

 

S

[Cheshire Freeze]

The GFS 18z has sniffed a bit of the UKMO coffee & has totally morphed towards the UKMO @ 96-

 

Probably not quite get there this run.... -  But watch the GFS ensembles collapse over the next 24-48 hours -

 

Were not saying anything mega cold - however there is night & day difference between the ECM/ GFS solution & the UKMO

 

S

 

Massive changes at just 114 between the 12z and 18z. Shocking.

 

P.S I've always maintained the GFS ensembles are next to useless

Edited October 4, 2013 by CreweCold

[Frosty.]

If it was another 4 weeks into autumn, that fax chart would be interesting, as it is early october, cold rain is the result, if by some fluke, it verified.

[smithyweather]

This is good because I want some frost and SUNSHINE. I hope this verifies as above and is a proper cold spell. 

[Cheshire Freeze]

At 132 hours HP parked over the UK rather than a southerly draw. Should at least get some seasonal, chilly and foggy nights out of this

 

[Cloud 10]

Subtle difference in the positioning of the high on the gfs 18z compared to 12z. 

 

18z..  12z..