Model output discussion - 7th January onwards

[Ali1977]

We finally have the ensemble graph breaking through the -10c 850 mark, and it’s the Op not a straggling Perb. Let’s see if it’s supported. The best part about it is we are t at extreme FI. Just one run though but still. 

[Purga]

A tad nippy for most!

Wind chill and blizzards anyone?

 

[chionomaniac]

It's amazing what a small sized wedge can deliver when the cold is being released from a disrupted TPV. Lovely FI and the sliders starting sooner than that. On track...

[Frosty.]

Looking at the Gfs 6z operational and indeed other model output so far today I would say..winter we have lift-off!!

Edited January 11, 2019 by Frosty.

[WhiteFox]

5 minutes ago, tight isobar said:

What an evolution..something 4 all..

As we swing between..cold airmasses..

Even the rammped nw jet..aiding things..

CRACKING STUFF...

 

Indeed. It is one operational run, but it shows the futility of deeply analysing each frame of each run past day 7. Indications have been in place for some time that we would probably be facing a cold spell from around that date. Ensemble clusters were strongly suggestive and, so long as there were runs showing cold conditions, we were bound to see one picked up in the operational run at some point.

The huge caveat is that this is one possible evolution still at the limits of reliability. I'm sure there will be plenty of posters who will cry "DOWNGRADE" when the next run does not show such a cold evolution. So long as the ensembles, overall atmosphere pattern and teleconnections support cold, the probability of cold remains fairly high regardless of Inter-run and inter-model variability.

Anything before 20th the hors-D'oeuvre IMHO. Watch the overall trend until we get within 5-7days!

 

 

[edinburgh_1992]

Excellent GFS06, loads of snow, especially for the north. Considering we have had only one day of snow this winter so far, the current outlook certainly looks very positive

[tight isobar]

4 minutes ago, WhiteFox said:

Indeed. It is one operational run, but it shows the futility of deeply analysing each frame of each run past day 7. Indications have been in place for some time that we would probably be facing a cold spell from around that date. Ensemble clusters were strongly suggestive and, so long as there were runs showing cold conditions, we were bound to see one picked up in the operational run at some point.

The huge caveat is that this is one possible evolution still at the limits of reliability. I'm sure there will be plenty of posters who will cry "DOWNGRADE" when the next run does not show such a cold evolution. So long as the ensembles, overall atmosphere pattern and teleconnections support cold, the probability of cold remains fairly high regardless of Inter-run and inter-model variability.

Anything before 20th the hors-D'oeuvre IMHO. Watch the overall trend until we get within 5-7days!

 

 

Exactly...

Ens viewing pivotal..

But the overall theme...is very stedfast..

And becoming moreso.

Edited January 11, 2019 by tight isobar

[WhiteFox]

7 minutes ago, Ali1977 said:

We finally have the ensemble graph breaking through the -10c 850 mark, and it’s the Op not a straggling Perb. Let’s see if it’s supported. The best part about it is we are t at extreme FI. Just one run though but still. 

Doesn't really matter if it does not have huge support so long as it is within a few degrees of a cluster of runs. We've seen the ensembles trend strongly towards a colder operational solution in the past. Once a colder signal is picked up by the operational, it often leads the way.

Having said that, expect more bumps. Experience tells us that the operational won't consistently follow the cold path until a bit closer to the time ..

[Empire Of Snow]

4 minutes ago, Ali1977 said:

We finally have the ensemble graph breaking through the -10c 850 mark, and it’s the Op not a straggling Perb. Let’s see if it’s supported. The best part about it is we are t at extreme FI. Just one run though but still. 

It isn't just one run. Even if gfs overestimates the LP, we have in our side 2 other scenarios which lead eventually to an Easterly/Northeasterly. And as you correctly said it's not FI anymore.

[Methuselah]

14 minutes ago, Frosty. said:

Looking at the Gfs 6z operational and indeed other model output so far today I would say..winter we have lift off!!

All roads lead to snow, Karl...I must disagree with Dave (TEITS) about the lack of deep cold, as any 850s of -10 or below are deep enough for me; I'd rather that than -18 anyway!

 

GEFS T850 ensembles for Suffolk: I make that 11 members ending between -5 and -10C:

Edited January 11, 2019 by Ed Stone

[Summer Sun]

Northern Blocking in full swing on the 1st met office ensemble mean map of 2019 for Feb to April

 

[WhiteFox]

9 minutes ago, Ed Stone said:

All roads lead to snow, Karl...I must disagree with Dave (TEITS) about the lack of deep cold, as any 850s of -10 or below are deep enough for me; I'd rather that than -18 anyway

Most roads lead to cold Ed! As good forecaster never gives guarantees...

Longer range forecasting gives us probabilities; numerical models are deterministic and based on imperfect information and so are also probabilities. Yes, the probability is high, but there are still a couple of unpaved roads which could lead to something different. Fortunately, I think we are now on the motorway!

[weirpig]

GFS ensembles  all over the place with the low at 150ish   some have it sliding some not   best keep a watching brief.

[shaky]

Hmm i like the parallel at 150 hours!!!wedge much bigger and atlantic low looks like sliding!!considering the parallel is meant to perform better than the normal gfs you would think it might have a better handle and prove to be correct but i guess it dont work that way does it lol

[Glacier Point]

Reasonable to conclude two things at the moment:

1: There will be a transition to colder than average conditions day 5/6.

2: The upstream flow across the southern tier of the US prevents any toppling of the ridge to our west and allows a second incursion of Pm air day 10, which entrenches cold into the European trough (more appropriately heads the jet NW-SE into the base of the trough advecting cold westwards).

Days 10 - 15 see further loaded potential to what has been advertised by the GFS op.

Edited January 11, 2019 by Glacier Point

[knocker]

I don't normally bother with the 0600 gfs but out of interest one has to note when it suddenly intensifies the a trop vortex lobe over the UK

And this

quickly becomes this

And

Edited January 11, 2019 by knocker

[Ali1977]

4 minutes ago, weirpig said:

GFS ensembles  all over the place with the low at 150ish   some have it sliding some not   best keep a watching brief.

They are going to be an epic set, some even earlier than the Op.

The mean in a week is very very good

 

Edited January 11, 2019 by Ali1977

[Methuselah]

3 minutes ago, WhiteFox said:

Most roads lead to cold Ed! As good forecaster never gives guarantees...

Longer range forecasting gives us probabilities; numerical models are deterministic and based on imperfect information and so are also probabilities. Yes, the probability is high, but there are still a couple of unpaved roads which could lead to something different. Fortunately, I think we are now on the motorway!

Good point, WF...I was getting carried-away. On my sledge of destiny!

[winterof79]

17 minutes ago, Ed Stone said:

All roads lead to snow, Karl...I must disagree with Dave (TEITS) about the lack of deep cold, as any 850s of -10 or below are deep enough for me; I'd rather that than -18 anyway!

 

GEFS T850 ensembles for Suffolk: I make that 11 members ending between -5 and -10C:

Wait for the  06Z set Ed

[Met4Cast]

GLOSEA update is incredible! More or less off the scale signal for Northern Blocking! 

[Penicuikblizzard]

22 minutes ago, edinburgh_1992 said:

Excellent GFS06, loads of snow, especially for the north. Considering we have had only one day of snow this winter so far, the current outlook certainly looks very positive

Hopefully nicely aligned to give Edinburgh a pasting ️

[tight isobar]

2 minutes ago, Daniel Smith said:

GLOSEA update is incredible! More or less off the scale signal for Northern Blocking! 

Glosea=astonishing !!!!!

[weirpig]

Short ensembles   shows  the difference of how the perbs  predict the atlantic to behave .  quite a difference toward day 7-8

Edited January 11, 2019 by weirpig

[shaky]

2 minutes ago, weirpig said:

Sort ensembles   shows  the difference of how they predict the atlantic to go.  quite a difference toward day 7-8

One of my.main concerns is that the control and op both go the milder way at day 7 or 8 and they keep on doing that!!even though the ensembles go the other way as long as the op keeps on churning out the same thing i expect it to be correct in regards to that slider!!really gota see a change on the 12zs and get that low to slide a bit more and if it does game on!!what really ticks me off is that if that was vice versa and the control and op on that chart were the opposite and colder at day 7 and 8 and all the other ensembles were mild you could almost guarantee that the mild would win!!you can never win lol!!

[karlos1983]

Nice Mean at +276

Some great GEFS purbs at +300 looking at the panels! Graphs going to look tasty!  

Edited January 11, 2019 by karlos1983