Model Output Discussions 12z 01/09/2016

[Turnedoutniceagain]

On ‎06‎/‎10‎/‎2016 at 12:40, Frosty. said:

A very unsettled, rather cold disturbed end to the Gfs 6z with some snow for the scottish mountains and I couldn't help noticing the arctic air bottled up and ready to swing south once that low pushes off further east..it will soon start getting very interesting!

Looks like the forecast for the 21st has slipped forward a few days

[MR EXTREMES]

well the iceland heights absolutely gutted!

but nice to see but just way to soon no cold air to the east,

we need a westward movement from them heights.

as a arctic or northeaster would be much much more likely to open the cold flood gates regardless how early in the season.

although it looks like a very powerful block if it been december or the end of nov we would be game on but right now not worth alot.

only that this pattern could rinse and repeat and could be a pattern at least for awhile also hearing the qbo is decreasing west and progressing towards east qbo still low solar min and hurricaine activity being more active.

but all the same nice model runs,

although we have been here many times before in october only to follow the garden path to a dead end.

Edited October 17, 2016 by MR EXTREMES

[Frosty.]

The Ecm 00z shows high pressure becoming centred to the north of the uk with low pressure anchored to the southwest and increasingly tightly packed isobars with more of an ESEly flow than the warmer SEly it was showing for the same timeframe on yesterday's output, subtle changes make a big difference..if only it was winter!

It's blocked

Edited October 17, 2016 by Frosty.

[Grimers]

The GFS model and the ECMWF model show a low over the Faroe Islands bringing moderate W winds and cool temperatures to all parts of the UK tomorrow and a high to the SW of Ireland bringing light NW winds and cold temperatures to all parts of the UK on Wednesday.

       

[knocker]

Small margins. The ecm takes the upper trough further south and west at the beginning of next week thus the surface low is further to the SW and the UK becomes the filling in the sandwich between the HP to the NE and said low pressure area. Ergo very unpleasant conditions in a strong E/SE wind.

Edited October 17, 2016 by knocker

[Met4Cast]

20 minutes ago, MR EXTREMES said:

well the iceland heights absolutely gutted!

but nice to see but just way to soon no cold air to the east,

we need a westward movement from them heights.

as a arctic or northeaster would be much much more likely to open the cold flood gates regardless how early in the season.

although it looks like a very powerful block if it been december or the end of nov we would be game on but right now not worth alot.

only that this pattern could rinse and repeat and could be a pattern at least for awhile also hearing the qbo is decreasing west and progressing towards east qbo still low solar min and hurricaine activity being more active.

but all the same nice model runs,

although we have been here many times before in october only to follow the garden path to a dead end.

 

People keep saying "it's a waste at this time of year" and I don't really understand why. Sure, from a UK perspective it's unlikely to deliver any meaningful cold or snow because of the time of year, but we're next getting excited about that. We're excited because all this Northern Blocking is helping to prevent the Polar Vortex from becoming fully established. During a month where we usually see the PV and Jet Stream gather pace and strength, we're not seeing that this year. 

The blocking is only there because background signals allow for it and all signs suggest its going to stick around. Might not be great for us right now but it will be a few weeks down the line. 

[simshady]

5 minutes ago, Daniel Smith said:

 

People keep saying "it's a waste at this time of year" and I don't really understand why. Sure, from a UK perspective it's unlikely to deliver any meaningful cold or snow because of the time of year, but we're next getting excited about that. We're excited because all this Northern Blocking is helping to prevent the Polar Vortex from becoming fully established. During a month where we usually see the PV and Jet Stream gather pace and strength, we're not seeing that this year. 

The blocking is only there because background signals allow for it and all signs suggest its going to stick around. Might not be great for us right now but it will be a few weeks down the line. 

Completely agree. If we want a decent cold, snowy winter then we have to start somewhere and what the models are showing are as good as we can get at the moment IMO.

[Summer Sun]

A late burst of warmth for parts of western Europe is possible next week 

ECM

GEM

Edited October 17, 2016 by Summer Sun

[booferking]

In lala land but nice to the see so early into the winter season.

[Zakos]

On the 06z the flow of WAA into the Canadian arctic is far more pronounced than shown on the 00z

This flow is more or less sustained throughout the duration of the run.

Im no expert but i believe this WAA is crucial to the building of heights around Greenland. 

We end up with this chart at the end of the run, what a fantastic way to start November. 

The chart may be in deep FI, but the GFS has been hinting at powerful heights over Greenland for a while, and all the building blocks are there.

Very encouraging IMO, and whats most encouraging for me is that we are seeing no sign whatsoever of a return to south westerlies, even in the depths of FI. Strange at the time of year when the Jet  really should be firing up.

Edited October 17, 2016 by Zakos

[Zakos]

The Kink in the jet stream to the west of Greenland as shown on the 06z (left) is what we want to see, rather than energy being sent in to the Atlantic on the 00z (right)

This is the area to watch IMO, though of course we could always get cold from the Scandi high if it is sustained long enough.

Edited October 17, 2016 by Zakos

[SMU]

As with Scandi High pressures & those even more rare retrograde Highs - The GFS has always been the last model to come ln board - always taking pidgeon steps to the euros - 

If you take it on a sliding scale what I have noticed is the ECM picks the over amplified solution & the GFS is always to flat, however generally in these scenarios the ECM slides back maybe 20/30 % & the GFS moves 70/80% so theres a meeting point & thats whats happening today-

The UKMO has a very good track record in these scenarios & looks excellent at 144-

As we now stand all ensemble Means at 192 have higher pressure development around the pole with slightly different levels of depth, however importantly the core of the cortex is dropping into Scandi East / western Russia-

Its all good news so far this October....

Edited October 17, 2016 by Steve Murr

[jvenge]

15 minutes ago, Steve Murr said:

As with Scandi High pressures & those even more rare retrograde Highs - The GFS has always been the last model to come ln board - always taking pidgeon steps to the euros - 

If you take it on a sliding scale what I have noticed is the ECM picks the over amplified solution & the GFS is always to flat, however generally in these scenarios the ECM slides back maybe 20/30 % & the GFS moves 70/80% so theres a meeting point & thats whats happening today-

The UKMO has a very good track record in these scenarios & looks excellent at 144-

As we now stand all ensemble Means at 192 have higher pressure development around the pole with slightly different levels of depth, however importantly the core of the cortex is dropping into Scandi East / western Russia-

Its all good news so far this October....

I imagine that would increase snow cover in that region?

[SMU]

Yes

look for the deep Scandi trough diving south around 26-28 th OCT

[Captain Shortwave]

Hmm looking at the output, I suspect blocking to our north or north east could well dominate to the end of the month and possibly beyond. The GFS tending to extend the blocking scenario and the ECM tending to move the trough further east as to keep higher heights over Scandinavia.

Day 10 operationals (GFS/ECM)

   

 

Ensembles for the same time, again GFS/ECM

   

So the idea of two ridges, one in the Atlantic and one to our east with a trough extending towards Iberia, the question will be how settled/unsettled conditions are and the temperatures will be dependent on the surface flow, a south or south easterly will probably be mild for the time of year, an easterly could drop temperatures back into single figures with frosts in the north. At this point I can't see a quick route to developing a wintry pattern, but conditions look rather slack and quiet with the tropospheric vortex located over Eastern Russia and the Pacific region.

Unlike previous years, the Canadian/Greenland region whilst occasionally seeing troughs develop, these are tending to be pretty shallow in nature and hence the very quiet jetstream across the Atlantic and that looks like continuing for the foreseeable future. It is certainly feasible that a cold blocking pattern could develop, either from the east (A high centred between Svalbard and Scandinavia) or from the north (Retrograde with a trough dropping south from the Arctic. It seems to me a case of not quiet yet with a changeable pattern persisting, albeit rather unusual for the time of year. 

 

[bluearmy]

The ens AO/NAO are starting to show a return to neutral/slightly above as we enter november

quite a way off but I guess exeters own models are looking this way too. 

I wouldn't be predicting a return of mobility based on what I can see on the ens data as yet though 

Edited October 17, 2016 by phil nw.
Quoted comments removed as for other threads

[Cheshire Freeze]

2 minutes ago, bluearmy said:

The ens AO/NAO are starting to show a return to neutral/slightly above as we enter november

quite a way off but I guess exeters own models are looking this way too. 

Fair enough, there is almost always a relaxation of the pattern before it emerges once more. I'd rather these synoptics reappear later on in November, which, given the strat charts I've seen looks a fair possibility.

[phil nw.]

Just a reminder please keep to views on the charts in this thread,any stand alone discussions on Met office forecasts should go into the general discussion threads.

Thanks all.

[MR EXTREMES]

wow gfs heights 1050mb and slightly futher west and from northern hemisphere looks really a very tasty chart.

i see matt tweeted displaced vortex and slight warming 09/10 started out of the blocks quickly like domino effect on the vortex and strat and add the southerly tracking jet.

but nothing especially cold infact pretty average most of the time 

Edited October 17, 2016 by MR EXTREMES

[Mucka]

Hopefully UKMO off the mark

 

Edit:

Just to elaborate, I'm not saying it is a terrible chart or anything. Plenty going on upstream and still blocked.

It is just that it is much less conducive to heights building into Greenland as far as I can see and once you get low heights forming around Southern Greenland it is often a precursor to the jet riding over the top and a flattening of the pattern.

Quite happy for folk to disagree with that as there is a fair bit of extrapolation and guesswork required to consider what 10 - 15 day charts would look like from there.

Edited October 17, 2016 by Mucka

[Ali1977]

GFS has a much better block this run, the Low to the SW is going underneath and the block is much stronger . A fair bit different to the UKMO update posted above by Mucka - which will the ECM follow I wonder. 

Edited October 17, 2016 by Ali1977

[Summer Sun]

Big differences between UKMO and GFS this afternoon at t144

[I remember Atlantic 252]

4 minutes ago, Summer Sun said:

Big differences between UKMO and GFS this afternoon at t144

all I know SS is we will have very wet start to half term, last 12 model runs or so shown itjavascript: viewimage(1);

Edited October 17, 2016 by I remember Atlantic 252

[MR EXTREMES]

gem close to being a record breaker for warmth in the south or se.

although would evolve nicely as heights are more east greenland iceland pretty much blocking the atlantic from going its usual route,

i believe the record  for october is 

A maximum temperature of 23.6 °C was recorded at Gravesend (Kent) and at Kew Gardens (Greater London) on the 31st.

but plenty of northern blocking looks like atlantic systems can only go under. 

Edited October 17, 2016 by MR EXTREMES

[Mucka]

GEM different again at 144

Blocking persists much further West.