Model discussion: Hunt for cold - into mid-January

[booferking]

4 minutes ago, Lukesluckybunch said:

ICON has the pattern further east at 72,not a great start

Icon is an slight improvement with pv and low on esb separation, but a long way to go till we get a direct hit like gfs 06z earlier.

[damianslaw]

The theme we can take from today's models is a probable greater level of amplification through the rest of the week than was being forecasted in recent days, all courtesy of developments over NE USA seaboard.. question then is the extent to which low heights over NE USA/SE Canada behave.

I'll leave if there for now.

[TSNWK]

Icon 120 flatter than 12z 126.. last chance saloon with 18z Gfs it is.

[That ECM]

3 minutes ago, damianslaw said:

The theme we can take from today's models is a probable greater level of amplification through the rest of the week than was being forecasted in recent days, all courtesy of developments over NE USA seaboard.. question then is the extent to which low heights over NE USA/SE Canada behave.

I'll leave if there for now.

Exciting though isn’t it? Although my wife doesn’t find it so. strange lady.

Edited January 11, 2022 by That ECM

[Uncertainty]

27 minutes ago, Cold Winter Night said:

We'll definitely get more answers on the short term developments and the GFS Northerly in the next few runs, but I wonder if those extended clusters really depend on that.

I get the impression that the EPS keeps more of the tPV east than it did earlier, instead of sending it all back to Canada.
There are more extended and stronger positive height anomalies to the North and West (Arctic and Atlantic) in FI than this morning (keep an eye on those), and that nice looking cluster 3 at 360h doesn't even look that great at 312h, but develops quickly.
So is that some new signal? Or a ghost? Something to keep us busy at least til the next run!

It’s been there for a few runs now. I’ve been through the perturbations though, no way there’s 14 that a human would match with the representative member in cluster 3. There’s 5, 7 at a push. However, they are very promising for cold fans considering where the EC46 has been for that period for weeks now (even though the last run backed off the zonality in W3).

I notice as well that each reinforcement of HP to the NW has been generally ‘under’ forecast across the modelling. Forgetting the GEFS for a second, here’s the day 10 EPS mean from Friday 7th

Now today’s 120

Huge difference off the Eastern Seaboard.

The EPS also underamplified this week’s U.K. high to an extent.

 I have long predicted a stormy zonal period late Jan / early Feb and so probably still would BUT…

should the MJO return strongly to P6/7

AND

We avoid a scenario where the SPV core  returns to Greenland and fully drives the trop pattern

Then charts like the below can start to make sense

 

Yes it’s the GEM ensemble at 384 but this morning it was totally flat (can anyone show me how to find archived ensemble sets for the GEPs or GEFS?), and if you look at the anomaly and compare to the seasonals or the recent 46’s you would take this in a heartbeat

 I’m guessing from the members and clusters the far reaches of the EPS would be very similar.

So it really is a puzzling picture recently of expecting the pattern to flatten in the extended but amplification keeps cropping up. Let’s hope that continues…

 

[sheikhy]

Just now, TSNWK said:

Icon 120 flatter than 12z 126.. last chance saloon with 18z Gfs it is.

Icon is terrible!!!i mean when you got the icon out gunning the gfs recently then massive questions need to be asked about the gfs which is meant to be a much better model and one of the top 3!!

[SqueakheartLW]

2 minutes ago, sheikhy said:

Icon is terrible!!!i mean when you got the icon out gunning the gfs recently then massive questions need to be asked about the gfs which is meant to be a much better model and one of the top 3!!

To be fair the ICON hasn't been on board with this northerly chance anyhow so can't read too much into that at this stage

Maybe it needs to be called the ICOFF, not the ICON

Edited January 11, 2022 by SqueakheartLW

[Lukesluckybunch]

4 minutes ago, SqueakheartLW said:

To be fair the ICON hasn't been on board with this northerly chance anyhow so can't read too much into that at this stage

Maybe it needs to be called the ICOFF, not the ICON

i called it at the start from very early on,because of the eastward shift, anyway to the 18z gfs

Edited January 11, 2022 by Lukesluckybunch
adding text

[Man With Beard]

So we're into a classic HP dominated winter pattern, where pretty much nothing happens over the UK for x many days.

However, it can still get very cold in this scenario. Only a little orientation move is required to keep the winds consistently off Europe, and at this time of the year, that can eventually get as cold as a northerly. Daytime maxes looking quite low next week on the ECM, and I wouldn't say ice days could be discounted yet.

[damianslaw]

Some have commented on the lack of imprint from strong E QBO and MJO stuck in phase 7 which might be expected to promote high lattitude blocking, alas I think these factors are having a significant affect and that is blocking and a sluggish jetstream.. we've had minimal storm activity and deep low pressure systems so far, despite a strong PV to our NW. No reason not to expect further continued strong amplification remainder of winter - and always prone to northerly blasts I feel.

[northwestsnow]

12 minutes ago, Man With Beard said:

So we're into a classic HP dominated winter pattern, where pretty much nothing happens over the UK for x many days.

However, it can still get very cold in this scenario. Only a little orientation move is required to keep the winds consistently off Europe, and at this time of the year, that can eventually get as cold as a northerly. Daytime maxes looking quite low next week on the ECM, and I wouldn't say ice days could be discounted yet.

For sure ..

Could be very cold at times ...

18z I suspect will hoist the white flag on a Northerly.

[Lukesluckybunch]

hi guys,if you dont mind me asking what are we expecting from the 18z? somthing similar to the 12z or will the trend dissapear...

[January Snowstorm]

Well eyes down for the 18z.

Almost everything against upgrades when one looks at the icon,gem,jma they all back the Ecm route. That's a lot of different models supporting each other. It isn't an exaggeration to suggest the month of January depends on the next 24 hours of runs because if we fail at the first hurdle it's a sinking high into Europe and its February!

[Kasim Awan]

Just now, January Snowstorm said:

Well eyes down for the 18z.

Almost everything against upgrades when one looks at the icon,gem,jma they all back the Ecm route. That's a lot of different models supporting each other. It isn't an exaggeration to suggest the month of January depends on the next 24 hours of runs because if we fail at the first hurdle it's a sinking high into Europe and its February!

Gfs 5% rest 95% imo.

[Anthony Burden]

Hi many times the odd one is the right one.

[TSNWK]

2 minutes ago, Kasim Awan said:

Gfs 5% rest 95% imo.

20/1 outsider is off and running…

[Scorcher]

27 minutes ago, Man With Beard said:

So we're into a classic HP dominated winter pattern, where pretty much nothing happens over the UK for x many days.

However, it can still get very cold in this scenario. Only a little orientation move is required to keep the winds consistently off Europe, and at this time of the year, that can eventually get as cold as a northerly. Daytime maxes looking quite low next week on the ECM, and I wouldn't say ice days could be discounted yet.

Not discounted but unlikely- they are certainly very rare in these parts, even in ideal setups. Probably relying on fog lingering for that to happen. We haven't had one here in the last two of winters, despite some rather cold setups.

[Cambrian]

Reinforcing a good deal of what many others have said,  the downstream effect of the mode of exit of the system from Canada places day 6 as the confidence crux for us, and it’s no clearer following the 12z runs today than it was after those of yesterday. There is so much ambiguity at the 144h timeframe, it’s hard to look much further ahead with even any small sense of surety. 

Here are the ECM and GFS ensemble means and spreads at 144h.

 
 

 

Both have a deep Scandinavian trough with the zone of greatest spread in the North Sea / Norwegian Sea areas. Both show wider spread over Greenland too. It’s still feasible that we could see greater amplification into southern Greenland and the Scandinavian trough further west come next Monday.

Also, for that matter, the markedly lower spreads over Iceland and western Russia show where the PV and associated troughing is much less  likely to visit.

Incidentally, have a look at that ghoulish monster face screaming at us from the Canadian lobe of the PV. It’s all gone a bit Scooby Doo there, hasn’t it?! No liability accepted for any accidents caused by anyone rushing to the bathroom after I pointed that one out. 

At this stage, for early next week, there’s still a wide range of possibilities to be resolved- it’s still most likely going to be a chilly high for us with a slack northerly supply, but there is also still some surprisingly resilient potential for a bit more of a direct northerly punch from the trough - seasonal weather for early January either way, and with the swings back and for, it could well take a couple more days to resolve. 

Fascinating model runs today and the pub run still to come!

[Ali1977]

No ridging at T84 between Newfoundland and Greenland, this would have been there if it was an improvement - if anything it’s already looking slightly flatter.  PV also stronger over Greenland and the trigger low not looking so apparent! 

Edited January 11, 2022 by Ali1977

[TSNWK]

Calling it st 90 the 18z will not be providing any fun-as  per previous two runs… our low to the west is further east and heights not building.. these tiny changes will extrapolate and expand as run proceed I believe…

Edited January 11, 2022 by TSNWK

[booferking]

9 minutes ago, January Snowstorm said:

Well eyes down for the 18z.

Almost everything against upgrades when one looks at the icon,gem,jma they all back the Ecm route. That's a lot of different models supporting each other. It isn't an exaggeration to suggest the month of January depends on the next 24 hours of runs because if we fail at the first hurdle it's a sinking high into Europe and its February!

18z is already moving the pattern further into Europe early on merging the pv together boring UK high it is what a troll GFS is useless.

Model Ranking

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2ND UKMO

3RD GEM

4TH JMA

5TH GFS

 

[Snowman.]

Trigger shortwave to save the day?

[tight isobar]

A tad more engaging here with the lonesome wave- and actually reinforces aid of advection/ and polar draw @ earlier!

[Ali1977]

Heights still having a good go at pushing up through the PV to Greenland at T126, which in itself gives hope that any shift back West overnight could make things interesting. 

[booferking]

1 minute ago, tight isobar said:

A tad more engaging here with the lonesome wave- and actually reinforces aid of advection/ and polar draw @ earlier!

It's pants mate let's be honest ECM showing a better Northerly now than ECM