Model output discussion - Winter approaches

[Sunny76]

Just now, daz_4 said:

Not sure if I agree with people saying "it's only middle of November, plenty of winter left." In my experience, the next four weeks will set the tone of the winter. Winters very rarely deliver (at least in Central Europe) if there is no cold spell from middle of November to middle of December. And based on today's runs we can probably write off at least the next ten days.

While I usually agree with that statement, I would say anything up until mid December is up in the air. A cold winter could still happen from that point on.

1984/85, 85/86 and 86/87 all had fairly mild spells during November and December, then the cold came during or after Christmas. 
 

2009, and 10, along with 12 and 17 winters did seem to produce some chilly weather before late November. 
 

 

[booferking]

30 minutes ago, mb018538 said:

That chart is utterly hideous. Flat NH profile and strong vortex. No thanks! An underwhelming set of 12z runs again. We’re going to have to play the long game as usual folks.

Unfortunately that's what metoffice going for up until end the of Nov dryer weather the further south east you go with frost fog & some unsettled interludes further north with chance wintry precipitation over high ground.

Its into December that things could get more interesting (ie) blocked & colder enjoy the chase.

[Lampostwatcher]

Just logged in for winter model watching

Not much to see atm 

Will be back when the beast from the east appears at t72

 

 

[Jeremy Shockey]

GFS 12 z

 Euro4 12 z

A bit of snow for the Scottish hills on Thur with the brief Northerly. 

Edited November 17, 2020 by Jeremy Shockey

[Blessed Weather]

A few posts discussing past winters have been moved over to the Early run up to Winter thread.
Model output discussions in this thread please. Thanks.

[Froze were the Days]

1 hour ago, Lampostwatcher said:

Will be back when the beast from the east appears at t72

See you in a few years then...

[MattStoke]

2 hours ago, Jeremy Shockey said:

GFS 12 z

 Euro4 12 z

A bit of snow for the Scottish hills on Thur with the brief Northerly. 

Welsh Mountains and Yorkshire Moors too based on that chart.

[damianslaw]

20 minutes ago, Premier Neige said:

 

GFS yesterday has three blocked outlooks longer term, today complete flip, only GFS can do this. Fully expect more flip flopping in days ahead.. 

.

[Mapantz]

Several posts moved over to the early run up to Winter thread.

As @Blessed Weather mentioned a few posts up - keep it to model discussion please folks..

Edited November 17, 2020 by Mapantz

[Ali1977]

Let’s see what today brings, but the overnight GFS definitely shifts the PV to the Russian side of the NH and away from Greenland, which is often a good thing for coldies. Northern USA and Canada would be exceptionally warm for the time of year with this set up. 

Edited November 18, 2020 by Ali1977

[joggs]

2 hours ago, Ali1977 said:

Let’s see what today brings, but the overnight GFS definitely shifts the PV to the Russian side of the NH and away from Greenland, which is often a good thing for coldies. Northern USA and Canada would be exceptionally warm for the time of year with this set up. 

And we still end up with a little shortwave feature to the west of us

Obviously it will chop n change.

[Weather-history]

Absolutely bonkers GFS ensemble in the extended range

[Mr Frost]

Morning all!

ECM 240 (I know...I know ) seems the way forward at the moment - from a purely IMBY perspective I am banking that all day long. 
Local higher hills/mountains for a snowy walk/hike at least! 

You know what they say...one man’s crock of  is another man’s treasure... 

 

 

 

Have a good day everyone and hopefully we get some eye candy (cold/snow) UK and Ireland wide into a reliable timeframe within the next couple/few weeks at least. 
Not excluding the risk of wintry potential tonight/tomorrow as discussed in previous posts. 

All the best!

Edited November 18, 2020 by Mr Frost

[blizzard81]

Ext Ecm ens for debilt. Not exactly mind blowing but I've seen worse as we enter December. 

[mb018538]

Longer term cluster one is awful today. Very strong +NAO pattern. Cluster 2 still holds interest.

[blizzard81]

Runs are looking a little more ridgy in the north atlantic on today's runs compared to yesterday. Compare yesterday's 06z run for next Tuesday to today's. 

[blizzard81]

3 minutes ago, blizzard81 said:

Runs are looking a little more ridgy in the north atlantic on today's runs compared to yesterday. Compare yesterday's 06z run for next Tuesday to today's. 

And again for next Wednesday. 

[bluearmy]

There are signs that as we head through week 2, that the Canadian vortex pulls itself away from influencing the nw Atlantic sector as we build a strong ne Canadian block - that will need to be watched ref how the tpv affects the n Atlantic around Greenland/Iceland 

prior to that it looks to remain mobile with everything chucked in - ridge, trough, disrupting trough, flat zonal !!

[Methuselah]

Deary me, doesn't the GFS 06Z look great ... plenty of drying paint to flow under the bridge, before we see any snow, methinks?

    

[IDO]

Yikes, tPV getting organised and powering up in FI:

Early>>  Later>>   

The modelling of the tPV may be GFS aligning with the spooling up of the sPV so I will treat that with caution.

Day 8 to D16 looks like the mixed westerly flow will swap to a UK HP on this run:

So no sign of a long-term pattern at the moment; a mixed bag, bit of this and a bit of that? 

[johnholmes]

Latest view from the 500 mb anomalies

Wednesday 18 th November

Ec-gfs and ec is trying to develop troughing down to n Africa with slight height rises w’ern atlantic with w’ly flow into uk; gfs has the trough just w of uk/Iberia so flow into uk is s of w; less +ve height rises w atlantic; over n America differences in far w with ec showing centre w of Alaska and gfs e of same

Noaa shows broad w’ly atlantic into uk but turning s of w with main ne Canada/Greenland trough influencing things, some tendency for lack of flow s of 50n as rounded trough extends towards Iberia, western n America and it has minor troughing off w coast and its main trough/low is well w of Alaska.

Nothing on any of these 3 somewhat similar charts (ec-noaa especially) yet suggests any marked wave change in the 6-10 day period; noaa 8-14 neither has any indication of this, with basically a w’ly atlantic flow into uk, slight signal for flow turning n of w into iberia

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

http://www.cpc.ncep.noaa.gov//favicon.ico Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[StretfordEnd1996]

It's looking chilly for a time in the near-immediate timeframe..

 

Is there evidence to suggest the jet is sinking southwards a tad in the more longer term, perhaps allowing better chance of some colder incursions from the NW/N

 

 

One may look, with a degree of optimism, at the 6z extended GEFS ensembles which in its more extended range show a marked cool down in the upper air temperatures (in contrast to what is often a huge degree of scatter at this range). 

(mean)

 

 

[BlueHedgehog074]

4 hours ago, Weather-history said:

Absolutely bonkers GFS ensemble in the extended range

From the view of the cold weather fans, how great that would have been if that was the Northerly we were getting tomorrow instead 

[Man With Beard]

Based on the latest ECM clusters, the modelling is reasonably well-weighted towards a zonal pattern between D11 and D15 (cluster 1). Storms likely, frost and snow not.

Cluster 2, which is far from an outlier cluster, offers something a bit more amplified - but experience from this model suggests coldies shouldn't be too hopeful that this will become reality.  Growing heights west of Greenland would give a chance of cold zonality for the UK, though, and could result in early wintriness for northern areas / high ground a few days after D15. But that's so speculative it's hardly worth mentioning at the moment.

[Methuselah]

Nice to see the 'building blocks' in place, by T+72!