Model Output Discussion 29th December - Into mid-Winter.

[karlos1983]

 

anyway, certainly looks promising tail end of next week, right on Q! 

Thats a pretty decent setup for a non transient cold spell! 

@Tamara post very much appreciated as always! Even though it hurts my brain! 

 

Edited January 5, 2017 by ajpoolshark
removed o/t stuff

[SMU]

Evening all-

No idea whats been posted so appologies if Im just churning the same info-

The next 10 days ( more especially the latter 4 ) represents the best opportunity for this winter for the UK to see something more widespread on the snow front-

Whilst the first low @96 gets East of the UK towards debilt, the pattern is already taking shape as the heights over russia & weakly over Scandi have proved to be much more impressive than originally projected - but not enough to back the cold over the UK-

As a result of the amplifiying pattern (backed up by the heights to the east) the UKMO comes up with the rather tasty 144 chart-

A very unstable polar blast pushing in from the NW with another system waiting in the wings behind it to bring perhaps some more organised wintryness-

Post that the ECM on a similar par, also inline with its ensembles shows a nice atlantic high ridging across a dropping Easterlies at day 11 ( ish )

ECM also @ day 10 shows a split vortex as well which in terms of modelling this winter hasnt been very forthcoming since mid november-

In terms of the strat - from T12 to day 10 shows the vortex being squeezed by a 2 wave pattern nearly forcing a split ( @feb1991blizzard) 

12 then onto 240

So me must keep an eye on the Berlin & GFS forecasts post day 11-16

have a good eve

S

@Catacol @Tamaraare you saying ( plus assuming tamara ) that no chance of cold- just at a time when we see our biggest chance all winter post day 7 -10 & when the strat looks like beginning to move to a more favourable position- ( although more time needed )

Of note is the CFS jumping back on the SSw trail again this morning...

just reading all the posts this evening I think in my world its fair to say that I dont really subscribe to the all the detail in the posts based on the fact that theres just to much 'spin' to make the peices seem like they fit up to now-

The only disconnect I see if theres much confidence in why X & Y have happened this winter thus far then Z should be easy to forecast- all to much hindcasting I think ... 

S

Edited January 5, 2017 by Steve Murr

[winterof79]

Trends.Not much use for a Nor Wester I imagine

[karlos1983]

2 minutes ago, winterof79 said:

Trends.Not much use for a Nor Wester I imagine

Yes, I'm not sure the Dutch ensembles are of much use to us at the moment are they?

guess it will be interesting to compare with London ens in an hour ish

[shuggee]

Lovely model output discussion in this thread remember please.  Few o/t posts hidden..... 

[Captain Shortwave]

14 minutes ago, winterof79 said:

Trends.Not much use for a Nor Wester I imagine

That would back up others suggesting we lose the maritime influence (Surface high or a continental flow) in the extended range somewhat. The set is certainly a good couple of degree colder compared to the 00z so that is progress. The operational is sitting nicely in the ensemble set too, pretty much on the mean throughout. Plenty of scope for a quite potent cold snap that could evolve into something more significant as we head deeper into week 2. 

The big question beyond the northerly is whether we see the Azores high nose in, the GEFs do suggest this at the moment with the lessening of the cold signal and becoming drier again. 

      

As we can see the high does nose eastwards again though the broad pattern remains similar with low heights draining south east into Europe, I guess the one way to spin this is the possibility of the suite being a bit progressive and hence too far east.

Overall the outlook looks good for northern and western areas, southern and eastern areas need the wind to back towards the north or north east or see a disturbance develop in the projected arctic maritime flow to bring a more organised band of wintry showers or prolonged precipitation to areas away from exposed coasts.

Edited January 5, 2017 by Captain Shortwave

[chris55]

13 minutes ago, winterof79 said:

Trends.Not much use for a Nor Wester I imagine

Often, when the De Blit 2m temps hover around 0c in the extended that's a good sign for us. Not based on anything scientific just past experience. 

And the Control.... that's blooming cold, with decreasing wind speed it may be from a cold high but hard to tell without the postage stamps.

[karlos1983]

32 minutes ago, Steve Murr said:

 

just reading all the posts this evening I think in my world its fair to say that I dont really subscribe to the all the detail in the posts based on the fact that theres just to much 'spin' to make the peices seem like they fit up to now-

The only disconnect I see if theres much confidence in why X & Y have happened this winter thus far then Z should be easy to forecast- all to much hindcasting I think ... 

S

Your last couple of paragraphs confuse me a little bit Steve. Enjoyed you commentary a couple of days ago, which didn't quite work out, fair doo's though, you stuck your neck out and I respect that.

but who is "spinning" what in their posts? That's lost me somewhat?  

 

Edited January 5, 2017 by karlos1983

[Duane S.]

I see where Catacol and Tamara are coming from, entirely. There appears to be very little in the way of tropospheric forcing to encourage amplification (in the right areas) and ultimately a proper cold spell for us here in the UK. However, I can also see where Steve is coming from as the forecast Strat (tropospheric disconnect aside) wave2 activity could be the one single catalyst we are looking for. Maybe a bit simplistic but it is far from insignificant and at worst will put a serious squeeze on the vortex, at best split it straight down the middle later on.

How the early winter cold spell got scuppered was a complete kick in the teeth as we were just damn unlucky.  The dice are IMO not (currently) as loaded as back then but that doesn't stop us rolling a double six. There remains potential, I believe that potential will continue to grow, let's see if we can eek out every morsel of it going into and through the second half of Jan. And then there is still Feb followed by March, plenty of water left under this winter's bridge!

[Zakos]

Agree with steve,best chance of widespread snow of the season coming up.

ECM mean for the 12th over the last 3 days shows a clear trend to build strong heights in the mid north atlantic, each run has weaker heights to our south, and deeper low heights over Europe.

ECM at 192

Very large block in atlantic, hinting towards atlantic high - siberian high link up.

If this verifies I would have thought we would be locked into a cold pattern. quite encouraging to see such an anomaly at just 192 hours.

Edited January 5, 2017 by Zakos

[bluearmy]

The control is unsettled cold but continuity on the control hasn't been there recently 

Edited January 5, 2017 by bluearmy

[feb1991blizzard]

Is the EC46 singing from the cold hymm sheet?

[Rocheydub]

1 minute ago, feb1991blizzard said:

Is the EC46 singing from the cold hymm sheet?

No access to it, but I know a man that does, and the man from DelMonte... He say "YES"

[Catacol]

38 minutes ago, Steve Murr said:

 

@Catacol @Tamaraare you saying ( plus assuming tamara ) that no chance of cold- just at a time when we see our biggest chance all winter post day 7 -10 & when the strat looks like beginning to move to a more favourable position- ( although more time needed )

O

No Steve - there is a decent opportunity for a good North Westerly blast coming up over the top of the mid lat ridge. But chances of that ridge getting to a higher latitude to sustain the cold look slim at the moment - at least to me. To be honest its been quite a cold winter down here so far overall.... but dry. 

But its only 5th Jan. Lots of time for change... and if a change happens in the background signals I'll certainly shout it out!

[bluearmy]

Week 3 seems to be indicating the potential for ridging over the top of the low anomoly which is interesting as that wasn't evident on the 00z eps day 15 which is what the 46 is derived from and yet it shows on the 12z in the latter stages

[radiohead]

I'm not sure how the rest of this 18Z GFS is going to go. But we are at T162 now with -8 uppers heading into Scotland and snow showers spreading in.

Edited January 5, 2017 by radiohead

[radiohead]

T192

[snowbob]

 

we have Steve Murr ,nick Sussex ,Tamara ,knocker,catacol,John Holmes, bluearmy, tight isobar, Karlos and so on( sorry if haven't mentioned all names but there's so many) so so many really good model readers on this forum who have taught many new comers so much.

best forum on the web

 

Edited January 5, 2017 by ajpoolshark
o/t stuff removed....please don't re-edit.....thanks

[radiohead]

A slight shift eastward on the 18Z reduces the snow potential window a bit on this run.

[StretfordEnd1996]

I'm not overly in love with the GFS18z tonight - the high pressure to the West seems to have shifted a little towards us compared to the GFS12z. 

 

I'm hoping it behaves itself a bit more for the rest of the run ... 
 

[cyclonic happiness]

The Azoroslug is saying 'no' again on the 18z to a decent northerly.   What on earth is keeping the thing there for so long? 

Still, there are signs that we may get a change soon.

[weirpig]

Quite a easterly correction the 18z however loads more scenarios to be played out over the coming days 

[January Snowstorm]

Poor 18z with everything shunted east.

Still cold but less ppn as the high moves in. As nick mentioned yesterday it sums up the winter to date to be getting excited about this.

Let's hope for an improvement over night 

[A.J]

no more posts on who does and doesn't post on this forum and the 'why' and 'why not' members post on this forum.....this is the model output discussion thread, the clue is in the thread title....and with that said, back to the model discussion please, thanks 

[blizzard81]

Let's hope the 18z is as useless as it usually is. Knowing our luck it will be spot on for once. It seems to be showing a Tamara/Catacol combo!