Model output discussion - The Hunt For Cold

[ICE COLD]

2 minutes ago, Quicksilver1989 said:

Retrogression to Greenland imminent? Much better from the 18z

Looks that way she's going up . Bye bye Atlantic . 

[Derecho]

1 minute ago, ICE COLD said:

Looks that way she's going up . Bye bye Atlantic . 

Until after T240 when GFS blows up a 950mb low in the Atlantic during the low res , or it will go to the other extreme ha.

[ICE COLD]

Cold air filtering in to Scandinavia. 

[bluearmy]

The idea of any meaningful retrogression towards Greenland has zero support from the eps clusters ........

 

[Don]

Just now, bluearmy said:

The idea of any meaningful retrogression towards Greenland has zero support from the eps clusters ........

 

Bump!

[Derecho]

1 minute ago, Don said:

Bump!

Yup nothing exciting going on in the later stages with the Polar Vortex organising once more over the arctic. Just a gradual cooling at the surface here under calm conditions.

[fromey]

Could this possibly come off???

its right at the end of the run so probably not but!!!

[Duane S.]

It’s the constant pulses of WAA, some solid vertical advection as well, that is what is making this look so promising. Huge potential for an early start to winter here.

The current strat trop relationship (or, lack of) is quite the sight to behold. 

[Geordiesnow]

The idea of the Euro high influencing our weather is getting more into the medium range now, the big question will be what orientation the high will be for the most part because it could be the difference with the well above average temperatures we are going to get from Wednesday to something a bit more cooler and of course the classic inversion conditions as a result. Either way, at this stage the models are predicting a very strong and robust block to develop so be interesting how this will develop.

Also if the high does not edge as far North and Westwards as first predicted and there is too much energy into the Northern arm of the jet then it means potentially yet more persistant rain for Northern Ireland which won't be welcomed after this week's deluges. 

[feb1991blizzard]

1 hour ago, bluearmy said:

The idea of any meaningful retrogression towards Greenland has zero support from the eps clusters ........

 

There are signs on the GEFS right at the very end of some sort of a Greenland block, tentative signs in that the process is just starting at the end of the run, the good news is that it is on a majority cluster by the looks of things, the bad news is its the GEFS!

[Kirkcaldy Weather]

P3  

P10    

P18   

P20  

P10 GEM 12z    

Oslo pressure on the rise 

 

[SLEETY]

11 hours ago, JBMWeatherForever said:

I really like the way the models seem to be bit by bit moving in the direction of a cold outbreak from somewhere between east and north before November is out. As is often the case in such situations, we may even be nearer to the start of a cold spell than is currently being suggested. Things are looking very interesting from a cold weather perspective.  

 

Gfs continues that move in the direction of a cold outbreak this morning.A very good run and UKMO has high pressure trying to retrogress toward Greenland.

[northwestsnow]

Lovely EC this morning with the anticyclone in full control at day 10.

[carinthian]

2 hours ago, SLEETY said:

Gfs continues that move in the direction of a cold outbreak this morning.A very good run and UKMO has high pressure trying to retrogress toward Greenland.

Yes, think UKMO looks the most robust of the models to strengthen the high pressure ridge over the British Isles by next weekend. In the meantime, plenty of warm air advection help this process with some very mild temps by Thurs/ Friday before colder surface starts to take affect. Sometimes this process can speed up just as we have seen in recent runs. Think GFS model is still uncertain regarding its 300mb jet projection in the latter stage of the runs, hence its variations of high pressure placement in its 6 hourly runs. The UKMO looks like it is going to retrogress the high NW wards. More runs needed. Back tomorrow with thoughts of our own team .

Edited November 11, 2018 by carinthian

[sorepaw1]

Looking at T+218 hrs and a little beyond 

A full flow easterly begins.

At the moment temps in Russia are around +1.oC. by day and -2.oC  by night.

And a North sea temp around +11.oC. 

When Eastern Europe and Russia cool right down. Next weekend. 

With this combination will be interesting for cold lovers imo.

 

[Ravelin]

I've just fallen in love with GFS p8... 

A definite tick downwards of the mean on the ensembles diagram for my locale at the end of the run, with the 'snow row' up to 20%. Way too early to start getting excited, but in the meantime it looks as if it'll be largely dry for the next week. 

[Methuselah]

When I was wittering on about the first attack of real cold coming in from the north or northwest, rather than the east, this is what I meant...Not that it'll happen either, of course...

[bluearmy]

8 hours ago, feb1991blizzard said:

There are signs on the GEFS right at the very end of some sort of a Greenland block, tentative signs in that the process is just starting at the end of the run, the good news is that it is on a majority cluster by the looks of things, the bad news is its the GEFS!

as I said last night the eps clusters not interested in a meaningful greeny height rise but the gefs idea of mid Atlantic ridge and developing scandi trough into week 3 was supported in the latest ec46 - timing, as ever open to some question 

[jules216]

I have been focusing on the NAO region over the last outputs as I believe that is a great indicator weather the Atlantic zonal train pushes through the establishing fragile block with a slight possibility of retrogression later, here are the overnight GEFS and EPS updates, looks to stay negative for a while,but we know how notoriously difficult is to forecast NAO even at a 5 day range. If the -NAO happens, I wonder are we seeing the first influences of solar minimum. Fascinating model watching anyhow

[northwestsnow]

5 minutes ago, bluearmy said:

as I said last night the eps clusters not interested in a meaningful greeny height rise but the gefs idea of mid Atlantic ridge and developing scandi trough into week 3 was supported in the latest ec46 - timing, as ever open to some question 

Hoping the trough over Europe will assist us longer term.

[feb1991blizzard]

Some signs of at least an Atlantic ridge (possibly Greeny) on the GEMS so would imagine the NAEFS mean would look slightly amplified at the end in the Atlantic.

[Duane S.]

Great charts to wake up to this morning. The UKMO especially keen.

I see the GEFS ens are ramping up their interest in retrogression and blocking to our NW itowards the far end of FI. An outside chance I suppose. A strong mid lat high should be the minimum expectation from this. Whatever occurs, very interesting to see how this plays out. 

One simple fact can always be applied when looking into the realms of day 10+ charts etc. If the OPs and the ens are consistently and predominantly showing zonal conditions, 95% of the time that is what we will end up with. If, like now, we have blocking showing and little, relatively speaking, zonal, as long as background signals don’t completely override this (which they don’t here), then we have at least a chance of picking up a decent cold spell.

It may be worth remembering that HLB showing on the forecast charts has cropped up more Novembers than not in recent times. Very few come to fruition. I do feel though, that we do have a better chance this time around. The QBO may be in a descending westerly phase but the easterlies are still at the right place for the troposphere to be the one calling the shots for a while yet I would imagine.

[feb1991blizzard]

4 minutes ago, s4lancia said:

Great charts to wake up to this morning. The UKMO especially keen.

I see the GEFS ens are ramping up their interest in retrogression and blocking to our NW itowards the far end of FI. An outside chance I suppose. A strong mid lat high should be the minimum expectation from this. Whatever occurs, very interesting to see how this plays out. 

One simple fact can always be applied when looking into the realms of day 10+ charts etc. If the OPs and the ens are consistently and predominantly showing zonal conditions, 95% of the time that is what we will end up with. If, like now, we have blocking showing and little, relatively speaking, zonal, as long as background signals don’t completely override this (which they don’t here), then we have at least a chance of picking up a decent cold spell.

It may be worth remembering that HLB showing on the forecast charts has cropped up more Novembers than not in recent times. Very few come to fruition. I do feel though, that we do have a better chance this time around. The QBO may be in a descending westerly phase but the easterlies are still at the right place for the troposphere to be the one calling the shots for a while yet I would imagine.

I think the retrogression signal has more than an outside chance, what exactly on the ground that leads to in terms of PPN type and where is obviously open to debate, BTW from memory we have actually had some blocking in recent Novembers but there havent been cold uppers to give us a pasting.

[northwestsnow]

2 minutes ago, feb1991blizzard said:

I think the retrogression signal has more than an outside chance, what exactly on the ground that leads to in terms of PPN type and where is obviously open to debate, BTW from memory we have actually had some blocking in recent Novembers but there havent been cold uppers to give us a pasting.

Absolutely agree Feb.. i was very suprised to see this option being pretty much dismissed last night and again this morning.

IMHO there is wayyyyyyy to much emphasis/faith put in these extended eps..

[Duane S.]

2 minutes ago, feb1991blizzard said:

I think the retrogression signal has more than an outside chance, what exactly on the ground that leads to in terms of PPN type and where is obviously open to debate, BTW from memory we have actually had some blocking in recent Novembers but there havent been cold uppers to give us a pasting.

I agree Feb, this one does have more legs than most FI eye candy fare, I was just playing cautious at this early stage