Model output discussion - Winter has arrived

[Griff]

I'm expecting a few wobbles on the road to wintry nirvana this week, who will be the first to crack? 

Having received a work call late on Saturday night to say a colleague had tested positive I'm now working from home so suspect I might be the first

Happy Monday and model watching!

Dense freezing fog again here this morning in South Oxfordshire just off the M40. 

FYI for some reason ying and yang comes to mind...  

 @ 144

Edited December 7, 2020 by Griff

[mountain shadow]

46 minutes ago, northwestsnow said:

EC mean continues to deteriate this morning.

That is a 10 day mean and isnt that bad.

It shows the PV far away to NW and higher pressure towards Scandi/Iceland with the jet to the South of the UK.

 

[southbank]

Wow - the GFS 0’s follows the trend of last night 18’s of at least a trending colder seasonal Christmas . Be interesting if the trend continues regardless of the actual surface details . I would gladly take 5 days off Xmas and rest a milder winter

 

quick question some folks have posted CFS charts last few days that also trended colder Christmas however for the likes of me I cant find those charts on the net ? If someone has a link I would be very grateful . 
 

so fingers cross the trend continues over the week

[I remember Atlantic 252]

meteociel CFS in google I do, not best anyway

Edited December 7, 2020 by I remember Atlantic 252

[northwestsnow]

8 minutes ago, mountain shadow said:

That is a 10 day mean and isnt that bad.

It shows the PV far away to NW and higher pressure towards Scandi/Iceland with the jet to the South of the UK.

 

If you  run the sequence the mean is building heights across Europe esp days 9 to 10.

 

[IDO]

I think looking at the bigger picture this possible pattern change is of more potential than the deadlock of block to our east. With the tPV pliant and def not the main driver we need to see as much forcing as possible. The Arctic high being modelled was injected from the Pacific with a small transient wave of heights. We see on the 0z gfs run, a wedge injected from a toppling Atlantic ridge. Surely whilst the tPV is compliant a standoff between Atlantic and Russian high in the vain hope of an easterly will just count down the timer? Saying all that, we still need those ridges and we need to be lucky where the pieces fall.

Looking at the gefs they are far more interesting than the runs from a day or so back with the omnipresent Russian high dictating our locale!

D12 gefs: 

[Bradley in Kent]

2 hours ago, snowlessayr said:

 

Looks a tad marginal to me 

On a more serious note, although unlikely to verify we do continue to see heights rising up towards Scandi or Greenland at FI on the GFS. if your wanting deep cold it is pattern you continue to want to see, if there is one decent thing about the GFS is that it can spot trends so at least it is something to keep an eye on for the next few runs.  I know some people tend to be pessimistic when models show cold but just remember how awful last winter was and enjoy the ride.

Although I am fairly young, I have been reading this thread for many years and it is massively helped improve my understanding of model watching. I decided to start posting now, finally. Some extremely knowledgable posters on here, thank you for all your insights. I know this place gets very heated at times but I think for most of us watching the models hoping for some cold and snow is a massive escape  from the world that we live in at the moment. 

Thanks 

Totally agree with this! I began looking the models  a long time ago without realising the learning potential on reading the forums! Makes me wonder why only this year but I'd probably say the content 'looked' a bit heavy for a 14 year old!

With regards to the latest models, a bit disappointing that the cold runs from last week aren't coming into fruition. Going to keep a close eye though with what that Russian High does and what with whispers of a warming stratosphere!

A Beast From The East over Christmas would be just perfect! (I am geared up for disappointment mind)

[DavidS]

1 hour ago, Nick F said:

IMO a reshuffle needed in the northern hemisphere pattern if we stand any chance of tapping into deep cold and proper snowy potential. The stalemate of high pressure block over NW Russia with low pressure stalling over or west of UK with upper flow energy feeding low heights over Europe is not going to deliver anything more sustained than what we've experienced. The trouble is, the high to the east is rooted quite far south, so there's no route for deep cold to get round then west to NW Europe, while its extension far enough west prevents arctic air reaching us from the north too. We need the NW Russian high to sink, models indicate this in the longer term.

It's looking increasingly like we will have to sustain the hardship of brief less cold Atlantic maritime flow for a few days, as low pressure moves in to the NW, strong support for this from the models. But this burst of upper flow energy over the Atlantic bringing this looks not to be sustained. With any surge from the west likely to weaken after 5 days.

Some interesting evolution by both 00z EC and GFS to our north days 9-10. GFS raises heights over Greenland driven, this time, by WAA from the Atlantic. While EC shows emergence of an arctic high into to Svalbard area, which is backed up the EPS mean. Both show deep cold over northern Siberia edging west towards NW Russia. The northern hemisphere generally looks very interesting, with the TPV not really consolidating this side of the northern hemisphere with wave breaking from the south this side and over Alaska preventing this.

00z EPS mean looking good at T+300, with +VE heights over Svalbard cross polar link up. TPV over NW Canada/Alaska.

00z GEFS indicates +ve height anomaly over Greenland quite far out, which is encouraging too.

One thing is clear from ensemble guidance recently is no strong signal for a strong TPV to return over Greenland.

Great post. Thank you.

[Methuselah]

Today's GEFS 00Z T850 ensemble... may be an outlier?

[Anthony Burden]

A small rise in temperatures is likely around 144 hrs to 168 hrs but nothing overly mild.

For how long this more slightly above average temperatures last is another matter.

anything over 144hrs take with caution,all models chopping and changing until they

get model agreement over several days.Great watching.

 

[DavidS]

2 minutes ago, General Cluster said:

Today's GEFS 00Z T850 ensemble... may be an outlier?

Or coffee smelling trend setter?

[TSNWK]

3 minutes ago, General Cluster said:

Today's GEFS 00Z T850 ensemble... may be an outlier?

Trend setter obs! :) top of the pack mid term as well.. not sure why and the impact longer term if that is wrong

[jules216]

I am surprised nobody mentioned that EC seasonal has updated. There are few positives to take home from these:

1. NAO meteograms still very negative for December and not that crazy positive in January either.

2. Nina showing signs of weakening rapidly in January 

3. MSLP anomalies JFM can with bit of imagination suggest NW flow in to Europe. Well at times at least because T2M anomalies are above 1C from mean 1993/2016.

[bluearmy]

39 minutes ago, northwestsnow said:

If you  run the sequence the mean is building heights across Europe esp days 9 to 10.

 

Euro height rises (moreso e Europe) strong days 8/10 on eps 

[syed2878]

2 hours ago, snowlessayr said:

 

Looks a tad marginal to me 

On a more serious note, although unlikely to verify we do continue to see heights rising up towards Scandi or Greenland at FI on the GFS. if your wanting deep cold it is pattern you continue to want to see, if there is one decent thing about the GFS is that it can spot trends so at least it is something to keep an eye on for the next few runs.  I know some people tend to be pessimistic when models show cold but just remember how awful last winter was and enjoy the ride.

Although I am fairly young, I have been reading this thread for many years and it is massively helped improve my understanding of model watching. I decided to start posting now, finally. Some extremely knowledgable posters on here, thank you for all your insights. I know this place gets very heated at times but I think for most of us watching the models hoping for some cold and snow is a massive escape  from the world that we live in at the moment. 

Thanks 

 indeed it might be picking up trends how over 24 hours ago this same GFs was bringing in the Atlantic so should we not wait for couple more runs

[booferking]

2 minutes ago, bluearmy said:

Euro height rises (moreso e Europe) strong days 8/10 on eps 

No height rises west or north of us could be a case rinse repeat need these height further north west to drag this cold air in from the north or east.

[TSNWK]

11 minutes ago, bluearmy said:

Euro height rises (moreso e Europe) strong days 8/10 on eps 

Drat! Or is it because of troughing into Central Europe pumping up heights to the east.. 

[Nick F]

3 minutes ago, TSNWK said:

Drat! Or is it because of troughing into Central Europe pumping up heights to the east.. 

Euro height rises in response to WAA ahead of amplifying trough to the west over the Atlantic in medium range.

Though GEFS and EPS differ how far west or east this deep trough gets, EPS mean further east into western Europe, hence E Europe gets the height rises.

[snowlessayr]

19 minutes ago, syed2878 said:

 indeed it might be picking up trends how over 24 hours ago this same GFs was bringing in the Atlantic so should we not wait for couple more runs

I literally said keep an eye on the next few runs 

 

Edited December 7, 2020 by snowlessayr

[TSNWK]

2 minutes ago, Nick F said:

Euro height rises in response to WAA ahead of amplifying trough to the west over the Atlantic in medium range.

Though GEFS and EPS differ how far west or east this deep trough gets, EPS mean further east into western Europe, hence E Europe gets the height rises.

Thank you.. so my take is yes to the heights around day 9 over europe  but cause is not the usual of jet riding over the top with low pressure pumping them up... we currently have modelled these euro heights as a temporary stepping stone for something with potential to be more palatable for coldies 

[Nick F]

6 minutes ago, TSNWK said:

Thank you.. so my take is yes to the heights around day 9 over europe  but cause is not the usual of jet riding over the top with low pressure pumping them up... we currently have modelled these euro heights as a temporary stepping stone for something with potential to be more palatable for coldies 

With the jet stream only cranking up in short bursts over the Atlantic, with the lack of sustained TPV/low heights to our NW to drive the more usual prolonged raging jet this time of year, troughing amplifying to the west would eventually cut-off, as per EC into an upper low over SW Europe, though GFS tends to take a lot longer cutting off troughs into upper lows for some reason, sometimes not at all. Though troughing/low heights over SW Europe may eventually lead to a conduit for upper flow energy over the Atlantic being directed south of the UK if height rises develop to the north as well.

[Froze were the Days]

54 minutes ago, jules216 said:

I am surprised nobody mentioned that EC seasonal has updated

 

55 minutes ago, jules216 said:

I know early days but don't think ec seasonal mslp for this month (from November) is going to be that accurate...

[jules216]

15 minutes ago, Nick F said:

Euro height rises in response to WAA ahead of amplifying trough to the west over the Atlantic in medium range.

Though GEFS and EPS differ how far west or east this deep trough gets, EPS mean further east into western Europe, hence E Europe gets the height rises.

Yes indeed what briefly looked like a WAA event west of Ireland where central Europe could benefit from downstream trough and cooling has been shunted to the east as usual so we remain in spring mode for foreseeable future. Again possible Euro cooling has been postponed to shakey evolution past day 10 pending bogus usual GFS la la la land charts, when you think how active some intentions a day ago here were about ScUral blocking peristing,this has been put in to bin replaced by hope now that Euro high might retrogress to Svalbard/Arctic or Iceland  as per GFS 384h

[Ali1977]

Height rises around Greenland much more noticeable even by day 6 on this run compared to the 00z. Latest run bottom image 

Edited December 7, 2020 by Ali1977

[IDO]

Nice to see two wedges in the high-latitude as early as d6:

We just need the Atlantic ridge to meet with the wedge to our north and if we are lucky the Arctic wedge?