model discussion Model output discussion 11th July onwards

[Eagle Eye]

Not sure it this is the right place to put this in but certainly something to look at in the future 

 

 

[carinthian]

Morning all, its that time of year when I can engage with the forecasting portal team over here. Snow cannons are in place and the primary question asked in resort is when can we use them ? Certainly looking at the latest UKMO at 144h , its going to turn colder into NW Europe , especially in to the British Isles . Its the longlivity of any colder weather that interests me. So I will give an insight of the professional views over here in respect to the chart below.  The problem highlighted appears the behavior of the developing low over Northern Labrador and its eventual position and movement . The expectation is to be just south of Greenland post 168h. Here lies the problem for the models as very cold air off the Greenland ice cap engages the very mild flow heading north in the west Atlantic. The result likely for a zone of high baroclinicity to form . So looking longer term with specifics to the British Isles the view is for a mostly NW flow of colder origins likely to prevail across much of the British Isles but with the positioning of the North Atlantic high open to much doubt at this time. Could be Southern England may return back to milder temperatures but with a lot of uncertainty at 168h and beyond. Hope this helps.

[LRD]

4 or 5 days of something slightly interesting and then, according to GFS 6z, it's back to tedium:

And eventually, basically, back to exactly where we find ourselves now:

A rhetorical question but what has happened to our 'autumns' (aside from being pushed into the Dec-Feb period, which was previously known as winter)? 

Edited October 27, 2021 by LRD

[Frosty.]

There is a moment when the ECMWF 0z ensemble mean looks fantastic for coldies with a cold plunge from the NNW… …beyond that, and this also goes for the GEFS, the pattern flattens out with heights from the south becoming more influential, at least across the south…now, bear in mind that it’s still very much autumn..so in effect, this doesn’t matter a jot! …what happens in autumn, hopefully stays in autumn!  

[swfc]

15 minutes ago, LRD said:

4 or 5 days of something even slightly interesting and then, according to GFS 6z, it's back to tedium

And eventually, basically, back to exactly where we find ourselves now:

A rhetorical question but what has happened to our autumns (aside from being pushed into the Dec-Feb period, which was previously known as winter)? 

I woudnt give up on the previous few days output. Variations and the usual caveats but give it 48 hrs

[Frosty.]

Looking further ahead towards mid November, the GEFS 6z shows some wintery interest which as you guys know, I will keep a close eye ? on!

 

 

[damianslaw]

Flow is predominantly NW dominated with a little wax and wane.. this is the direction of travel.. I expect models will overreact to any tendency for heights to seek to build back in from the SW. All the forcing will be from the NW.. jet aligned NW-SE predominantly but not exclusively.

[Cambrian]

On the 6z GFS run, again as it did a couple of days ago, the control favours the maintenance of the jet stream on a NW-SE trajectory through the later stages, while the operational run flattens it west-east for a while at least. 
At 288h, operational / control 

 
 

This makes a big difference just a little later in the run, at 324h, with the operational placing us in a mild southwesterly, while with the control we’re under low pressure in a northerly, the NW-SE trajectory maintained through to the end of the run. 
At 324h, operational / control

 

Edited October 27, 2021 by Cambrian

[Frosty.]

As I said in my earlier post regarding the GEFS 6z mean showing the pattern gradually flattening out with heights to the south becoming more influential beyond the cool unsettled NW’ly next week….well, this is also what the Gfs 12z operational shows…it doesn’t bother me because any cold at this time of year realistically wouldn’t amount to a hill of beans (for the majority) unless it was something truly exceptional! …still, I haven’t given up on something truly exceptional occurring before the meteorological winter begins!   

 

Edited October 27, 2021 by jon snow

[SLEETY]

Shows its pointless following gfs in fl,the huge difference between the runs in  the last 24 hours,is typical of the model,until it starts showing some sort of consistency ,then its a waste of time looking at it.

[LRD]

13 minutes ago, jon snow said:

As I said in my earlier post regarding the GEFS mean showing the pattern gradually flattening out with heights to the south becoming more influential beyond the cool unsettled NW’ly next week….well, this is also what the Gfs 12z operational shows…it doesn’t bother me because any cold at this time of year realistically wouldn’t amount to a hill of beans (for the majority) unless it was something truly exceptional! …still, I haven’t given up on something truly exceptional occurring before the meteorological winter begins!   

 

Yep got to agree

The trend to return us to utter tedium in about 8 days intensifies on the 12z

And then introduces a pattern where it looks a long way to anything interesting

I'm not even bothered about cold at this stage. If it's going to be mild then a good old gale with heavy rain/lively showers would be something. Just can not abide mind-numbing dry and mild nothingness during these next 4 months or so

Edited October 27, 2021 by LRD

[Frosty.]

Coldies won’t like this! …mild outlier?…anyway, it’s what the Gfs 12z op is showing…almost worth a BBQ on Nov 10th!

 

[LRD]

If only it was August:

 

[LRD]

12z Control (GFS) run out to 216 and agrees with the Op run

The majority of Netweather members watching these runs:

[I remember Atlantic 252]

6 minutes ago, LRD said:

12z Control (GFS) run out to 216 and agrees with the Op run

The majority of Netweather members watching these runs:

For some members like me, want these charts to come off! it's still FI so probably downgrade to low pressure, will have had enough rain here after next Tues

[SLEETY]

OP and control can agree at 216 means jack, at that timeframe. even at 120 hours things can go pear-shaped especially if cold is concerned in the winter months!

[damianslaw]

Too much flip flopping in GFS today.. instills little confidence in it.. these changes are beyond reliable prone to large margin for error. 

[LRD]

1 minute ago, I remember Atlantic 252 said:

For some members like me, want these charts to come off! it's still FI so probably downgrade to low pressure, will have had enough rain here after next Tues

Hence why I said majority of members mate. Whatever is your thing is your thing / each to their own and all that but, for me, I can't stand what I call 'non-weather' through these next 4 or 5 months. It's from now to late Feb/early March when I like to see the kitchen sink thrown at the UK most of the time - whether that be wind/rain or cold/snow. Or, failing that, at least some fog and frost (whatever happened to the frosty/foggy autumn high?) Especially as nothing very spectacular happens in the other 7 or 8 months of the year. 

Anyway, keeping this on topic, here is the extended UKMO run at 168. Looking like it will follow the GFS trend to me:

[swfc]

55 minutes ago, SLEETY said:

Shows its pointless following gfs in fl,the huge difference between the runs in  the last 24 hours,is typical of the model,until it starts showing some sort of consistency ,then its a waste of time looking at it.

Tbh SLEETY is just for fun. Changes in the 144-168 and earliercan and will alter the complete run. The recent cool /cold runs are reliant the PV not developing of the esb /labrador. The riding is scuppered by the emergence of it. as a side note ecm flipped also so the subtle changes coming into play have big ramifications 

Edited October 27, 2021 by swfc

[Cheshire Freeze]

Charts have flipped from delightful to horrendous in the longer range today

Would rather see it in November than December/January though!

[LRD]

Not quite the full spaghetti ensemble set but up to 10 Nov, the Op and Control are at the top end in terms of 850 temps, with limited support from other members from about the 5th:

In fact, the Control is an outlier for about 18-24 hours. So, slightly better news for those who would like to see more seasonal/active weather for November

Edited October 27, 2021 by LRD

[Methuselah]

Well, not wanting to waste my time trying to make sense of all the flip-flops the models are currently producing, there's always the Met Office's take:

 

[LRD]

Last frame from ECM

Flat

High pressure attracted to mainland Europe like a fly to something brown

[Frosty.]

2 minutes ago, LRD said:

Last frame from ECM

Flat

High pressure attracted to mainland Europe like a fly to something brown

I will say this about the ECM 12z operational…it’s trying…very! 

[northwestsnow]

8 minutes ago, LRD said:

Last frame from ECM

Flat

High pressure attracted to mainland Europe like a fly to something brown

Flat is one word...

Really hate these synoptic in November

+NAO setting up ...