www.wetterzentrale.de/maps/GFSOPEU12_288_1.png

Return of the surprise snow events

 

This looks even more 'interesting' and the repeat of the pattern perhaps more so.

 

Edit: with this jetstream profile - the LP off the eastern seaboard is heading north

---

Is this GFS run a one off or beginning is something impressive?

 

 

Will that low have the capacity to send WAA to inflate the GH?

 

 

---

It will be interesting to see the latter stages of the 12z GFS ensembles. The chances are this is one of those random rogue runs we get in
FI every so often.

---

yes quite possibly an outlier but some interest non the less. Also an illustration of what can happen out of the blue so to speak 

Might also explain why the GEFS are handling any potential PV disruption with more vigour than the Op runs, which seem far less interested.

---

Anyway, nearly all the GEFS seem to have LP anchored over Scandi at T+240, with those showing any form of mid-Atlantic ridging opening the doors to colder air from the N/NW.

---

Maybe the FL of GFS might just verify ,can only remember one time it did.
Think it picked up a northerly for Xmas day two weeks out,and it actually happened?
Like trying to throw the double six and once in a blue moon it hits 3 times in a row

GFS teasing with hints of something colder from the N/ NW again in the middle distance. I wouldn’t bet against that outcome.

---

ECM has it as well that patch of warming is causing a lot of uncertainty

TBH I don't think the outlook is particularly interesting at all. The northern hemisphere profile couldn't be much worse than GEM and ECM are showing at 10 days ahead. Apart from some modest bubbling in the North Atlantic the pattern looks as flat as a pancake.

 

ECM t+240

 

GEM t+240

---

I would love to see the GFS 12z op run for Dec 11th-12th to be right at this range for the first time ever. Imagine the constitutional havoc that would cause with all those polling stations cut off! 

---

To hell with flat pancakes - now that GFS can model them, we want irregular shapes!

 

---

---

be brave the cold spell is coming, the warming is going to inflate the high for a watered down jan 87

Focusing on the predicted moderate strat warming amd subsequent gph profile, vortex shape (all just forecasts of course) their may be some merit to what the gfs and ecm are showing in the mid to long term. Way to far out really to comment further but at least something to watch perhaps.

Not a bad run for early December 🙂

GFS should please coldies as yesterday's zonal stuff is now cold zonal, with incursions of northerlies at the end of each NW-ly spell. Anyway, HP over the UK for the start of next week (Mon 2nd, buut some rain in SW first), zonal at the end of the week turning N-ly by Mon 9th; then back to a weaker HP on Thu 12th (doesn't really get to Scotland) and repeat, but with LP striking down into the N Sea by the 14th (echoes of Jan 1953?) and a new outbreak of N-ly over the UK

ECM less emphatic about the first N-ly and the second beyond its normal confidence

GEFS cold to 3rd, then mild to 7th (5th in Scotland) then scatter but with mean below seasonal average. Rainfall from 7th but not much of it.

Also to note, appearance of some very cold air in N Russia in week 2, and moving eastwards http://www.wxmaps.org/pix/temp4 but in the companion site, a lot of rainfall for the UK especially the south at this time http://www.wxmaps.org/pix/prec4 contrary to GEFS.

For now the snow covered area is N Scandinavia and then well east into Russia https://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow_asiaeurope.gif

BBC last night presenting a change in the jet stream over the US - a persistent big southerly loop breaking into smaller waves) affecting the UK downstream in due course and linking it to the NW-ly tendency noted above.

 

---

I have to agree with Brian, things don’t look very interesting at the moment with a big well organised vortex over the pole and a fairly flat belt of high pressure to the south. At least we have a few days of brighter and more seasonal weather coming up over the weekend. Hopefully by the time the next band of rain arrives there will be something more exciting showing up in mid December on the models.

---

Can’t disagree Rob. Looks typical cool zonal to me to early Dec.

The Eurasian strat warming is underway, and although it stalls fir a week, is persistent and increases again into w3. Constant pressure on the vortex at 10hPa is likely to have an effect lower down as soon as the strat troph connection gets going so there could be some major pattern shifts coming up in the long range.

Then again the Lib Dem’s think they can get a majority so we live in uncertain times 😉

---

I appreciate that strat warming doesn't necessarily happen every year. However, am I right in thinking that, when it does occur, it generally happens later in the winter and that early winter strat warming is unusual?

---

That would require the political equivalent of a Maunder Minimum and a severe SSW simultaneously.

---

The natural cycle of the sun's influence with the changing of seasons creates the cooling/warming cycle in the strat over the pole, so yes later in winter when the sun starts to have more of an influence then there is a natural warming trend.

Such a warming in late autumn/early winter (albeit in this current case, a modest warming) is therefore at odds with this natural cycle, but is not necessarily particularly unusual. 2009/10 was a recent example.

---

Think it's worth highlighting the GEFS has been quite consistent recently. The plot below is from 00z run on 24/11. At that time there was still discussion about a lengthy cold period and the Met Office were at least partially on-board with the idea.

---