Model Output Discussion Autumn 2024

[northwestsnow]

18z control brings heavy snow showers from the NE ..

VERY low likelihood but nice to see GEFS playing around with some cold options.

[Penguin16]

 Don I think differently, take whatever we can get . If we get it early all the better, better than approaching mid February with absolutely nothing by that stage. 

[Allseasons-Si]

 northwestsnow ,it is very 2010 esc,...and i have said that twice in two day's,...hmmm!!!

interesting model watching for sure.

[Kirkcaldy Weather]

 bomdabass

Nothing unusual it's due to the tropically sourced moisture from the cyclonic developments in The North Atlantic part of which has became Tropical Storm Patty discussed in my posts here

 

 

Becoming linked within the Anticyclones

As discussed in the Global thread there are some discrepancies between the models on the handling of the current MJO progression with a few notes I'm making

• GEFS, GFS + GEM op all indicative of a strengthening of the Anticyclone in Ireland And The UK during November week 2 potentially circa 1040hpa
• CFS keen on a very strong MJO Event - Below Average 200mb Velocities as they progress across The Indian Ocean

On 28/10/2024 at 06:43, Kirkcaldy Weather said:

From the above we can see the feedback leads to a common combination of a +PNA, -AO + -NAO, (latest observations and outlooks not quite there with the AO and NAO though the timing is only til just about Mid November lets see how they go) with anticyclonic developments  - Above Average Pressure in The Arctic, North Atlantic Ridge developments which extend into Greenland and link with the -AO, Cyclonic developments across Scandinavia with multiple areas of possible storm developments 

• SW of Ireland And The UK 
• The +PNA cyclonic track from The Gulf Of Mexico > Northeastern USA possibly The Canadian Maritimes

Switch to a -PNA, paired with the NAO & AO heading toward Neutral and negative phases continues to hold plenty of interest for potentially Below Average Temperatures, Significant And EXTREME Above Average Temperatures and Drier And Highly Anomalously Drier Than Average conditions continuing in the mean time

Credit

 

Climate Prediction Center - Teleconnections: Pacific North American Pattern

WWW.CPC.NCEP.NOAA.GOV

 

Climate Prediction Center - Teleconnections: North Atlantic Oscillation

WWW.CPC.NCEP.NOAA.GOV

 

CPC - Teleconnections: Arctic Oscillation

WWW.CPC.NCEP.NOAA.GOV

Cheers, KW

Edited November 4, 2024 by Kirkcaldy Weather

[RJBingham]

A gradual drift down to average for a day or two, before trending milder again.

[AO-]

Morning all, 

There appears to be pretty much agreement between models within the first 10 days with only small variations on the theme. HP retrogressing a little west. The day 10 chart of EC this morning is pretty interesting. It is what we have seen in GFS as well already. Appears to be some kind of split in the tPV with a lobe over Canada and a big one over Siberia.

Edited November 4, 2024 by AO-

[TSNWK]

 AO- huge potential for our high to be sucked up between the vortex lobes Canada and siberia

Potential! Another one struck of the netweather.tv bingo card

Edited November 4, 2024 by TSNWK

[TSNWK]

 RJBingham disagree with trending milder at end. 

Flatlands a couple of degrees above 850 mean  

Probably rather chilly at surface 

[AO-]

As a comparison to my previous post here is the day 10 chart of GFS. Mind the resemblance.

[northwestsnow]

Hoping we see some more seasonal weather as we head towards mid month certainly signs the anticyclone may get far enough North to cool things down

 

[carinthian]

Morning all . Just look at those 850mb temps currently over the Alps. I can confirm this morning the temp is 13c at 2000m with clear blue skies. The frost level again at 4000m. November records have been broken on many peaks in Salzburgerland for the highest min and max temps. Models show a slow drop in uppers this week as the warmer air heads towards the British Isles. Hope you get some breaks back home to enjoy the warmth of the early November sunshine before the cool down takes place the following week.

C

Edited November 4, 2024 by carinthian

[bluearmy]

Continuing the theme of a weak meridional jet stream and blocked pattern

heights seem keen to ebb and flow to our west (which was predicted in the monthly outlook for November)

will they drop to our south to allow any cold incursions to make it across nw europe ?  Not sure we should care for now.  Encouraged by the models continuing to want to disrupt the lw trough to our sw.  
the spv looks to be strengthening to be well above average second half nov.  predicted to be centred just on the Asian side of the pole so if it does effectively couple down to the trop that’s better than it being on the Canadian side. (Unless it was a long way west).   Not ideal but not a complete disaster either - and (am I imagining this)  - a v strong spv so early in the season can be followed by a reversal early enough to have an impact before spring! 

Those references to 2010 keep cropping up ………

 

[Cambrian]

Definitely growing interest in the Scandi trough idea for later in the month from the 0z GEFS.

Even though it’s out at the highly tentative day 16 time frame, the shift since yesterday’s 0z at the even more tentative day 17 is notable. Yesterday’s / today’s.

  

There is a surface low pressure now being modelled over Scandinavia, with the core PV declaring much more overtly for Siberian Arctic residence. Rather it than me. 

Regarding our discussions of the stratosphere, the zonal winds at day 16 are set to surge sky high, to near 40 m/s, so it’s wrapped tight high up and coupled well too, but all quite discernibly on the Eurasian side. The anomalous warmth on the Asian side reaching around to Alaska is shepherding the core to the Eurasian side. 

  

Comparing the eddy heat flux chart for today with that for day 15, we lose the poorly coupled profile with the three lobes - Aleutian, Atlantic, Siberian troughs, in favour of a well coupled profile with a unified core on the Eurasian side, extended in the troposphere to Aleutian and Scandinavian troughs. There’s also a “cut-off” trough over the Hudson Bay area, feeding heights up into Greenland and supporting the growing Atlantic ridge signal.
  

With the main action being so decidedly on the Eurasian side, despite the ramping up in the strat, the setup still allows for heights to work through to the pole from Greenland, enough to maintain semblance of a polar high at the surface.

(I think I might just be beginning to get to grips with how these eddy flux charts work and I’ve got to be honest and admit that I am over the moon! Stratospheric in fact, but with the good feeling reaching down into my very troposphere.

All a couple of weeks away, with all the caveats and cautions as a cacophony of attached bells and whistles, but nevertheless, growing interest too in the models moving forward for us guys after an exceptionally quiet start to November. 

[TSNWK]

06z has the right idea at day 10..

Might be a nice FI

[Lukesluckybunch]

12 minutes ago, TSNWK said:

 

06z has the right idea at day 10..

Might be a nice FI

 

Yes looks to be going in the right direction,great to see the day 10 chase back on!at 264 looking for that trough to dive south with the jet heading towards Spain,let’s wait and see,this looks very good way out ,the whole PV looks to be transferring East away from Greenland 

Edited November 4, 2024 by Lukesluckybunch
Adding

[Ali1977]

I’d take that for mid November

[TSNWK]

 Lukesluckybunch good to see you mate..

 

ready for another season of drama

[feb1991blizzard]

First cracker of the new season up and coming.

Its November 5th tomorrow but looks like the fireworks have started early.

Edited November 4, 2024 by feb1991blizzard

[Lukesluckybunch]

3 minutes ago, TSNWK said:

good to see you mate.

You also TSNWK,yea I’m ready for the drama

3 minutes ago, Ali1977 said:

I’d take that for mid Novembe

Hi Ali,agreed good building blocks there!

[throwoff]

 feb1991blizzard She's a beaut!

[feb1991blizzard]

 throwoff

Yes - very good so early anyway.

[throwoff]

 feb1991blizzard too many years chasing to feel confident in any way.

The long term model thread is depressing at the moment!

[TSNWK]

And thier off!

Great to see familiar faces emerging from Sumner slumber as the 1st eye candy gfs teeze rolls out 

Next bingo word! 

Downgrade by 4 30

Edited November 4, 2024 by TSNWK

[throwoff]

 TSNWK The summer hibernation ends, the tracking of the Medway Snow Shield begins...

[Tim Bland]

Let the games begin