Model Output Discussion - The Start Of Winter

[bluearmy]

Interesting GEFS coming out,5 with Easterlies at day 12 along with a few Northerlies...

Yep - looks like they are beginning to smell something.

[Duane S.]

Just catching up on the charts. This ummm sort of caught my eye...

Over 40 degrees!?! That will likely have far reaching effects as far as the vortex reformation is concerned. Smack on time as well. That is SSW territory

[phil nw.]

Yep - looks like they are beginning to smell something.

Maybe Nick.

Some juicy looking ens even by day 10 with height rises east and west of the UK trough.

Will they lead to anything yet though.Still a lot of members maintaining that Greenland vortex into week 3.

[SMU]

Yep - looks like they are beginning to smell something.

 

PTB 12 touting the week 3 change.....

 

http://www.meteociel.fr/modeles/gefs_cartes.php?code=12&ech=6&carte=1&mode=0

S

[Frosty.]

Wintry showers will spread to southern areas during Friday and Saturday. It's great to see cold reloads galore for as far as the models go with just short lived milder intrusions. With Christmas almost in range, I think there is a good chance of a white one for parts of the UK.

[gottolovethisweather]

Friday is still a day of model output confusion with regard to that secondary low feature, which could yet pack some surprise snowfall as I alluded to earlier, along with another period of local gales. Even though it is only at D3, the surface analysis coming out of the ramifications caused by the slow passage of tomorrow's system mean that evolutions beyond D3 are likely causing cross-model inconsistency.

 

Here's tonight's D3 offerings as things currently stand.

 

 

I'd suggest official's eyes will firmly be on the next 24 to 36 hours so don't expect too much attention to paid to this second event just yet. 

Edited December 9, 2014 by gottolovethisweather

[SMU]

Friday is still a day of model output confusion with regard to that secondary low feature, which could yet pack some surprise snowfall as I alluded to earlier, along with another period of local gales. Even though it is only at D3, the surface analysis coming out of the ramifications caused by the slow passage of tomorrow's system mean that evolutions beyond D3 are likely causing cross-model inconsistency.

 

Here's tonight's D3 offerings as things currently stand.

 

ECM 12z 091214 t+72 hours 1300CET 121214.png

 

I'd suggest official's eyes will firmly be on the next 24 to 36 hours so don't expect too much attention to paid to this second event just yet. 

 

Hi Gotta-  look at the trough line running out SW through SW Scotland & NI

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014120912/ECU1-72.GIF?09-0

 

all that moving SE into wales & the NW.....

 

S

[Mucka]

ECM 120 leaves UKMO out on its own with the flatter pattern.

 

[terrier]

Well we have the gfs and ECM now with a much flatter pattern looks like ukmo out on its own tonight. Think after the next 72/96 hrs we may be glad of some calmer conditions.

[gottolovethisweather]

Hi Gotta-  look at the trough line running out SW through SW Scotland & NI

 

http://www.meteociel.fr/modeles/ecmwf/runs/2014120912/ECU1-72.GIF?09-0

 

all that moving SE into wales & the NW.....

 

S

 

Is the trough line you refer to, that which is shown by the kinks in the isobars as there is another lot running from the South of Ireland through to North Wales on your image? If so, yes it looks interesting and this secondary feature could yet move a 100 miles North or South of where currently projected IMHO making all the difference to who might get some wintry stuff and who won't.

Edited December 9, 2014 by gottolovethisweather

[gottolovethisweather]

ECM 120 leaves UKMO out on its own with the flatter pattern.

 

 

Delayed ridging of the Azores High into Southern Europe again I would think too. Best let the run run and await the mean ensembles before getting too excited for coldies though. Plenty of positives despite a lack of entrenched cold and with much snow on the mountain tops and hills (not exclusively so) before we get to D6 and beyond as well. 

Edited December 9, 2014 by gottolovethisweather

[Barry12]

Well we have the gfs and ECM now with a much flatter pattern looks like ukmo out on its own tonight. Think after the next 72/96 hrs we may be glad of some calmer conditions.

 

It's the other way round, the UKMO has the flatter pattern...

[Mucka]

Delayed ridging of the Azores High into Southern Europe again I would think too. Best let the run run and await the mean ensembles before getting too excited for coldies though. Plenty of positives despite a lack of entrenched cold and with much snow on the mountain tops and hills (not exclusively so) before we get to D6 and beyond as well. 

 

Yeah but it then phases that low a little later anyway and flattens things but run to run variations will happen.

 

 

I guess I will join the rest of the crowd looking at the finer detail of the upcoming spell for now less it pass me by. (with one eye on the upstream pattern and FI develpments of course,. )

[Duane S.]

Well we have the gfs and ECM now with a much flatter pattern looks like ukmo out on its own tonight. Think after the next 72/96 hrs we may be glad of some calmer conditions.

??? Lost me. 'UKMO out on its own' in what respect?

[Buxton Codge]

Well we have the gfs and ECM now with a much flatter pattern looks like ukmo out on its own tonight. Think after the next 72/96 hrs we may be glad of some calmer conditions.

ECM still suggests a fairly average December pattern for next week.

[gottolovethisweather]

Yeah but it then phases that low a little later anyway and flattens things but run to run variations will happen.

 

 

 

I guess I will join the rest of the crowd looking at the finer detail of the upcoming spell for now less it pass me by. (with one eye on the upstream pattern and FI develpments of course,. )

 

Unfortunately, yes at t+192 hours or so, the Azores High tries to influence our weather, at least in the South of England and on your second comment, absolutely nothing wrong with doing that as it is all certainly valid model output discussion and what a fantastic selection of knowledgeable folk we have in this very forum thread. Personally, it looks possible that my "gut feeling" signal from four days ago could become the new trend for the longer-term but as ever time will tell but I re-quote a section from it for anyone who is interested.

 

"Whether by Mid-December we see the current coolness relent is up for debate, but to my mind, mid-December onwards we're more likely to see a drier picture develop as Xmas approaches and I can almost hear the weatherman saying at least "it won't be mild". Admittedly, the last bit is beyond model projections and is a kind of fantasy prediction from my "gut", however, these gut instincts can often come true too."

 

Beyond all that, a fair bit of movement of the Siberian High and a ramping Jetstream in the pacific putting pressure on the Polar Vortex and potential for a SSW, small wonder this forum buzzes at the mere thought of these longer term prospects.

Edited December 9, 2014 by gottolovethisweather

[Captain Shortwave]

Apart from the chance of an occasional polar maritime spell popping up, there isn't much to suggest anything other than a average December set up with winds predominantly from the west with rain and strong winds at times. The UKMO is most keen on bringing drier weather to the south of the UK by day 6, the rest remain unsettled throughout pretty much.

Edited December 9, 2014 by Captain shortwave

[nick sussex]

A very uninspiring ECM run, flat as a pancake upstream and the Azores high moving into southern Europe. It's 00hrs ensemble mean didn't support this Azores high love-in so hopefully this operational run is not some new trend.

 

Ghastly is being kind to it!

[Mucka]

??? Lost me. 'UKMO out on its own' in what respect?

 

I think the observation Terrier makes is the wrong way around and it is UKMO that is flat but it is on its own in that it is the only one that phases the Canadian low with the main vortex which allows the Azores high to ridge further East and keep the trough shallower and a flatter pattern develop thereafter. All the other models keep that meandering low as a closed low and so are less flat be day 6.

It is the same reason as ECM flattens out later as that low bursts East and phases with the main trough.

 

 

Edit:

small correction. JMA is similar it just phases it a little later.

 

 

You can see that closed low and from the start of the output and how its behaviour affects (or not) each output in our part of the world accordingly.

JMA still manages to get some cold air across us later but nuances aside we could do with that low staying closed off until later in the output when it could even be a help rather than a hindrance.

Edited December 9, 2014 by Mucka

[blizzard81]

The ECM's persistent scrooge like output is starting to

worry me a little. The ensembles have been terrible for days now and the last couple if op runs have shown strong heights to our south. The Siberian block really needs to step up to the plate and start retrogressing soon. It seems to have been stuck in it's homeland for what seems like an eternity now. I hope the ECM op is a mild outlier.

[gottolovethisweather]

Apart from the chance of an occasional polar maritime spell popping up, there isn't much to suggest anything other than a average December set up with winds predominantly from the west with rain and strong winds at times. The UKMO is most keen on bringing drier weather to the south of the UK by day 6, the rest remain unsettled throughout pretty much.

 

Loads of snow on the hills in the more immediate forecast though, which was missing last year of course but yes, nothing astoundingly cold. However, only next Tuesday and Thursday I think it was, look remotely mild to be fair. Cold rain doesn't float everybody's boat I know but we are certainly entering a period of high-octave action with increasing amounts of snow potentially anywhere away from the South (still debatable at short-range even here?) and especially favouring those with elevation on their side. SEASONAL sums it up nicely, so if this average, I'll take it for now.

Edited December 9, 2014 by gottolovethisweather

[I remember Atlantic 252]

The ECM's persistent scrooge like output is starting to

worry me a little. The ensembles have been terrible for days now and the last couple if op runs have shown strong heights to our south. The Siberian block really needs to step up to the plate and start retrogressing soon. It seems to have been stuck in it's homeland for what seems like an eternity now. I hope the ECM op is a mild outlier.

 

Think we will welcome it, at least it looks dry, most of us in the south will be fed up of the rain by then, FI anyway

[nick sussex]

The ECM's persistent scrooge like output is starting to

worry me a little. The ensembles have been terrible for days now and the last couple if op runs have shown strong heights to our south. The Siberian block really needs to step up to the plate and start retrogressing soon. It seems to have been stuck in it's homeland for what seems like an eternity now. I hope the ECM op is a mild outlier.

Yes its frustrating, its dropped loads of colder solutions in its later output during the Autumn lets hope it suddenly hasn't found some FI reliability.

 

I was holding back from going into one over the last few days because generally the NWP has kept the Azores high displaced and not moving into limpet position over southern Europe.

 

Of course the Azores high there is really just a reaction to the upstream pattern which as you can see could hardly be flatter.

[blizzard81]

Yes its frustrating, its dropped loads of colder solutions in its later output during the Autumn lets hope it suddenly hasn't found some FI reliability.

I was holding back from going into one over the last few days because generally the NWP has kept the Azores high displaced and not moving into limpet position over southern Europe.

Of course the Azores high there is really just a reaction to the upstream pattern which as you can see could hardly be flatter.

Yes Nick, we just need Ian to pop in now and say last night's cluster signal has vanished! Trying to muster something positive from that ECM run but it's difficult. Maybe the high to our south gets sucked west by the high exiting the States post 10 days? That might keep some cold options alive as we go forward but it's all desperate conjecture I'm afraid. Edited December 9, 2014 by blizzard81

[blizzard81]

Think we will welcome it, at least it looks dry, most of us in the south will be fed up of the rain by then, FI anyway

I know what you are saying but it would be preferable to have those charts in summer.