Model output discussion - 5th December 2016 - Into Winter we go

[Allseasons-Si]

Just bet me to it Knocker

i was just about to post those anomaly charts from noaa,and was going to say that is there a split flow there with a segment of pv over N Canada and the other segments over Siberia/Russia and +ve height's Greenland linking up with the Aleutian +ve height's,also more of a -ve height's into the med?

could there be a spit in the pv as we go further into Jan

temps and dew points trending colder as we enter Jan too with quiet a few snow spikes

 

could this period be reflected on the slight warming that we had mid to late Nov given the time lag of a few weeks,but the temps have fallen away at both 10hpa and 30 hpa of late,i don't know much about the strat but i do know that if there is no increase in temps on these two charts within the next month then we might and i stress might be game over for any decent shot at a cold spell so we will have to wait and see if there is any increase in temps as we progress through Jan

cheers all and  merry Christmas

 

 

Edited December 23, 2016 by Allseasons-si
spell check

[johnholmes]

8 minutes ago, Ali1977 said:

Hopefully GLOSEA and other METO models are still seeing this potential cold snap, I'm just hoping it can last till the 2nd week of Jan. 

Well it looks unlikely to start before the 1st week anyway. That is judging by the NOAA anomaly charts, not showing anything on the 6-10 other than the centre of gravity of the +ve heights still moving west. By the 8-14 and the ridge and +ve heights are there giving a north of west flow into the UK. Rare for this to show first on the 8-14 and not the 6-10 but also unusual for this model to have it totally wrong. Will post more tomorrow morning with charts.

In my very simple chart watching the 30mb chart was the one I used to use some years ago. Taking 10-14 days from when it crossed the average line, ascending in T was what I used as a rough idea of 'possible' cold weather, note I said possible. It worked about 60% of the time so maybe another indication that things are moving towards a cold outbreak in early January?

Edited December 23, 2016 by johnholmes

[Allseasons-Si]

2 minutes ago, mountain shadow said:

Neither of these show a blocked Atlantic. If they did, the ridge would be away up onto Greenland.

They are mean charts MS and not the ops,that's a pretty good ridge on the ecm to my eye

[Man With Beard]

Evening all, this is the scenario I've been looking forward to as it is, for me, the big test for the new updated ECM. Does it still do too much with heights towards Greenland, or has it sorted that one out now? A fine chance to find out coming up...

[Iceberg]

12 z gfs p is out and has a dogs dinner of a mess for January. However it also has plenty of snow for January so make of it what you will.....

imho they are good ecm eps mean charts. Without seeing the groups of the members it's difficult to draw much of a conclusion accept their must be plenty of support for the ops. 

[Daniel*]

 

Well EC 500mb GPH ens mean anomoly out at day 10 is certainly not playing Scrooge.. building the ridge further north compared to the OP and at a better axis to Greenland/Iceland.

Europe going cold! 

 

Edited December 23, 2016 by Changing Skies

[mountain shadow]

26 minutes ago, Allseasons-si said:

They are mean charts MS and not the ops,that's a pretty good ridge on the ecm to my eye

I know what they are but as means they do not show a blocked Atlantic. A decent ridge is not a block.

[WINTRY WALES]

So going from Joe B's, Judah Cohen and Michael Ventrice tweets they are all in agreement about us entering a cold period come the start of Jan....are they all singing from the same hymn sheet here with regard to what they are seeing from the latest models?? If so surely this must be a huge step in the right direction with regard to confidence?? 

[Allseasons-Si]

16 minutes ago, mountain shadow said:

I know what they are but as means they do not show a blocked Atlantic. A decent ridge is not a block.

Forgive me if i am wrong here,the mean(i don't think)will not show a block of sorts but a ridge compiled of members into that area to give some trend

just for comparison/example taking the forecast mean for 2nd Jan 2016 at 240hrs compared with the current one 2nd Jan 2017 at 240hrs,i know which one i would take

 

Edited December 23, 2016 by Allseasons-si

[kumquat]

Alaskan ridge pushing through the pole. That's surely going to exert some forcing of cold into mid latitudes in our vicinity?

[Allseasons-Si]

Not happening on this run(just one run though) and i am not downbeat just yet,what i do like about this run though is that Aleutian ridge is a lot stronger into the pole.that will have some ramification going forward,i hope. 

[DIS1970]

I wouldn't bother looking at tonight's GFS output - if you don't want to get too depressed.

 

[mountain shadow]

2 minutes ago, DIS1970 said:

I wouldn't bother looking at tonight's GFS output - if you don't want to get too depressed.

 

No one should be depressed because numerous old hands have warned of what was likely to occur.

 

[Allseasons-Si]

3 minutes ago, mountain shadow said:

No one should be depressed because numerous old hands have warned of what was likely to occur.

 

Do we know what is likely to occur though,it's just one run!

i give it a day or so,and if by then nowt shows in terms of this northerly then i will hold my hands up

[Mucka]

8 hours ago, Ed Stone said:

I know I really shouldn't say this (but why the hell not!): it could all 'flop' back again, come the 12Z...

Fortunately they have stayed flipped for now but yeah lots of flopping going on too.

[mountain shadow]

24 minutes ago, Allseasons-si said:

Do we know what is likely to occur though,it's just one run!

i give it a day or so,and if by then nowt shows in terms of this northerly then i will hold my hands up

I admire your fortitude but I will save you the bother. There will be no Northerly other than a  brief 12 hour affair for a lucky few.

[Paul_1978]

1 minute ago, mountain shadow said:

I admire your fortitude but I will save you the bother. There will be no Northerly other than a  brief 12 hour affair for a lucky few.

What do you make of the background signals etc in the tweets from Ventrice, Cohen, Bastardi et al?

[Ali1977]

Some pretty tasty ENS out there from the pub run, early Jan still looking much better for coldies - look for a day of upgrades tomorrow. 

[Paul_1978]

1 hour ago, WINTRY WALES said:

So going from Joe B's, Judah Cohen and Michael Ventrice tweets they are all in agreement about us entering a cold period come the start of Jan....are they all singing from the same hymn sheet here with regard to what they are seeing from the latest models?? If so surely this must be a huge step in the right direction with regard to confidence?? 

You would think so! But the op output is frustratingly not playing ball yet!

[Jason M]

Some good GEFS but no convincing signal and not really coming forward through the timescales. I suspect were being beckoned up that well trodden garden path again.

No doubt the output is better than it was earlier in the week, but I can't help thinking the models are up to their old tricks of over amplifying again. Lets see what the morning brings.

 

 

[booferking]

More colder blocked options appearing on 18z Ens so not over yet its not just about the northerly around new year its the 2nd wave that follows right after and nearly every ens shows a 2nd wave love the ups and downs of model watching its what brings us here.

If it works out it works out if it don,t its not the end of the world enjoy coldies.

Merry Christmas to you all.

Edited December 23, 2016 by booferking

[Allseasons-Si]

4 minutes ago, mountain shadow said:

I admire your fortitude but I will save you the bother. There will be no Northerly other than a  brief 12 hour affair for a lucky few.

Thankyou

12hrs is enough to get snow on the ground

from derailing this thread more so i will end it there,whilst there is (dare i say it) potential,i remain optimistic for now 

[SMU]

Evening all-

no change from the earlier post- Near zero chances of a greenland high in the near term ( sub day 12 ) thereafter - possibilites depending on how slow the strat zonal jet gets & if we get any decent wave break forcing from the trop, however to be fair this winter ive seen page after page littered with MJO this & that when in reality its added very little to overall hemispheric proceedings - especially in our neck of the woods... I take little notice of it now unless there is something major within the forecast- which hasnt been the case - all very low amplitude stuff..

S

Edited December 24, 2016 by Steve Murr

[Scandinavian High.]

Just catched up after my Christmas party. We are are going in the right direction for a cold snap - colder spell January .

[Daniel*]

1 hour ago, mountain shadow said:

I admire your fortitude but I will save you the bother. There will be no Northerly other than a  brief 12 hour affair for a lucky few.

I think that's an ignorant take on things - things are going the right way IMO clearly we're not there yet, well London ECM 12z ensembles are definitely trending colder. One run even has a low of -11C that would take exceptionally cold air from the east. The mean goes for daytime highs of 5C in London early January the 'prominent' cluster goes for daytime highs no higher than 3C in London! Clearly we need to see this brought forward. Nonetheless we're in the best position we've been in all winter, but that says a lot doesn't it. 

Edited December 24, 2016 by Changing Skies