Model Outooks: Winter 2008/2009

Snowaddict

mike65 wrote: »

Looking at wetterzentral its a 3/4 days wonder.

Although its very unlikely, if that T+240 chart verified, the pattern would become sustained and continuous, it would be very hard to break down IMO.

Either way, its a corking ECM run compared to previous GFS runs.

I might be being over optimistic, but this would eventually equal a cold outbreak.

Snowaddict

kerry1960 wrote: »

Excuse my ignorance SA but where is the cold in this chart ? the source of that circulation seems to me to be African/Med in origin ??? .

not questioning anyone's chart reading skills or anything , just wondering .

Well the T+168 chart is as far out as I can get the 850hPA temps at the moment, thats for the 27th.... So if you run the pattern further, it should be turning much colder, I could be reading things wrong though...

arctictree

I must say the 12z ECM looks good tonight.

Has anyone noticed that the more HP in our vicinity, the more accurate the longer term forecasts seem to be? I suppose this has to do with chaos and less fluctuations in the models. With one LP after another rolling in from the Atlantic, anything after 6 or 7 days seems to be totally FI.

In the current setup, there seems to be a lot more consistency in the models at long range.

Trogdor

The ecm ensembles for de bilt seem fairly certain that the cold will reach there anyway
http://www.knmi.nl/exp/pluim/Data/PLUIM_06260_NWT.png

Deep Easterly

ECMWF 12z 850's for 00hrs 29th:



Cool, DRY, crisp, healthy, breezy...

Perfect. :cool:

Snowbie

arctictree wrote: »

I must say the 12z ECM looks good tonight.

Has anyone noticed that the more HP in our vicinity, the more accurate the longer term forecasts seem to be? I suppose this has to do with chaos and less fluctuations in the models. With one LP after another rolling in from the Atlantic, anything after 6 or 7 days seems to be totally FI.

In the current setup, there seems to be a lot more consistency in the models at long range.

If the HP is strong at 1040mb +, it can block the jet and thus block the Atlantic(depending on where its located). It can meander around but where it meanders, the difference in temp/weather can vary somewhat. How close, how far, how north and south it is usuall exerts an influence over us. It's how strong they can get can be spotted and called for certain T120hrs out.

ninebeanrows

Were on the verge so to speak.

This winter was always gonna deliver.

Let the upgrades continue.

Its gonna happen this winter

Yes i've had a few beers...................:pac:

WC's enternal optimism.

ninebeanrows

Snowbie wrote: »

If the HP is strong at 1040mb +, it can block the jet and thus block the Atlantic(depending on where its located). It can meander around but where it meanders, the difference in temp/weather can vary somewhat. How close, how far, how north and south it is usuall exerts an influence over us. It's how strong they can get can be spotted and called for certain T120hrs out.

I don't even take too much notice of the models this year, its always the same theme.

It IS gonna happen, anyone agree?

Snowaddict

I certainly am much more upbeat when I see the 18Z ensembles.
Next weekend could even be very interesting. A clear cooling trend is also evident.

Pangea

Is it still possible that we will have a winter colder than any in recent time ,maybe like the 63 or 80s?
That cold wave that will plummet temps into -10 or less.

Supercell

18z keeps the high further north so I suppose is an upgrade. Still dry as a bone though.

Supercell

00z is a slight upgrade, that high is going to be hard to nail down methinks right up until Christmas day probably.

Supercell

Brr is all I can say! :-

Snowaddict

Some comfort is that GFS operational was yet again an extreme mild outlier for the 00Z run... Many members trending well below right out to the 5th/6th Jan.

I still think cold to very cold weather could potentially arrive in the east, especially if we see more members dipping towards -10 for next weekend.

I think that any retrogression towards Greenland will take a while - into the new year, but I don't think this high will sink anytime soon. ECM also very good again this morning.

Snowbie

GFS 06z has no retro of the HP into GL not even into FI. Again no cold prolonged spell more cool than cold and well out into FI we keep pressure high over Scandi. Winds back more to the south later in this run alowing the Atlantic to push in only to be blocked again and winds back east again.

Maybe an interesting spell between Christmas and New years when a cold pool floods across the East and SE.

Kippure

Its looking cold towards the end of the month once again

Snowbie

GFS 12z keeps a southern Norway positioned high which keeps a SE flow over Ireland.
850mb temps not too cold but height thickness decreases.
Then the HP slips into Europe allowing a southerly flow up over the country in FI on 30th/31st.

By all accounts not a good run for cold.
A couple of hours untill the 12z ECM is released.

Pangea

Im losing faith in all theses charts etc.
I find it hard to understand , one chart a few days ago suggested a big freeze and now its a bit different,
What makes it different , are these charts guessing what will happen based on the current weather conditons or what
Have any of these long forecast charts in the past been accurate? :rolleyes:
Im just curious .

I Quote

"SEVERE COLD WAVE TO HIT EUROPE"

''The development of a major blocking high pressure system over the north atlantic and its subsequent backing west is about to throw most of Europe into the coldest winter weather pattern in many a year. In fact, Temps over the next month or so are liable to average 6-10 degrees F below normal over the center part of the continent with the northwest coldest last, but still getting into the games. Intuitive with this is the likelihood of more than normal snow and ice. As the upper block backs west, arctic discharges from the north and east are liable to bring shots of severe cold back into England and with it enhanced snowfall''."

Is this still relavant?

arctictree

Interesting comparison now between GFS and ECM.

At t+144, the models are very similar but start to diverge after that:

GFS:


ECM:



By Tuesday, ECM is going for a north easter while GFS is going for mild southerlies. Couldn't be more different:

GFS:


ECM:


At this stage, all we can be sure of is some cool easterlies on XMas day and a few days after. After that we need to look for an LP breakdown or sustained easterlies for any snow potential.

Snowaddict

Another fantastic and very interesting run from the ECM output again this evening. The difference between it and GFS is certainly stark in the longer term.

However, ECMWF has been very consistent on the last few runs, so I think retrogression of the high is quite possible - it won't sink in my opinion.

I wouldn't be surprised if GFS operational comes back on board maybe tonight or tomorrow. I just don't see ECM doing a total turnaround on this (although this does not mean it won't happen).

ECM would certainly deliver colder weather to Ireland, I haven't got a chance to look at the 850 hPA temps, but I do think its very interesting and shows great potential for a classic blocking and retrogression setup.

Lets see what the next few runs of both models bring.

Its going to be turning colder from midweek onwards, the question is just how cold, and can something memorable be delivered?

Its still all to play for IMO.

TheGreenGiant

Hey guys, did anyone watch the weather forecast after the 6.01 news today? At the very end of G.Murphy's forecast I noticed that there were 3 HP'S: the one over us, one over Scandi and one in central Europe? Would this be bad for our chances of snow flurries getting this far west of Europe with those easterlies breezes and all the HP over Europe. Of course it could all change, but just wondering.

Snowaddict

Pangea wrote: »

Im losing faith in all theses charts etc.
I find it hard to understand , one chart a few days ago suggested a big freeze and now its a bit different,
What makes it different , are these charts guessing what will happen based on the current weather conditons or what
Have any of these long forecast charts in the past been accurate? :rolleyes:
Im just curious .

I Quote

"SEVERE COLD WAVE TO HIT EUROPE"

''The development of a major blocking high pressure system over the north atlantic and its subsequent backing west is about to throw most of Europe into the coldest winter weather pattern in many a year. In fact, Temps over the next month or so are liable to average 6-10 degrees F below normal over the center part of the continent with the northwest coldest last, but still getting into the games. Intuitive with this is the likelihood of more than normal snow and ice. As the upper block backs west, arctic discharges from the north and east are liable to bring shots of severe cold back into England and with it enhanced snowfall''."

Is this still relavant?

Still a bit too early to tell IMO, but if the latest ECMWF charts continue to show and if they verified, then yes the above statement could well be apt. However, I'd like to see GFS operational come on board again within the next few runs.

Greetings from a rather mild prague.
I see the gfs is acting the maggot with your hopes and desires SA.
None of the regulars on here including me pay the kind of heed you have been to far FI GFS.

Be aware that ,it's either going to end up like jan 2007 with the others following suit and a very weak easterly or we're going to have something good out of this.
I'm not going to call it.I know the forecasters over here are talking of colder for later in the week but only barely sub zero by day..
That said they are not going beyond Stephens day..
Like was said weeks ago,you'd need to see daytime maxima here below -6 or -8c to be confident and a low down the med somewhere to strengthen the flow of that chill west.
It's so rare it's an awfull lot to ask for.

Also I'll add that the GFS is poor and always has been from what I'm told in dealing with reverse zonality so it's all up for grabs but again an awfull lot to ask!

I won't be able to look at the models that much if at all over the coming days so who better to ask than yourself to post up summaries for me

In the meantime I must get back to my rather strong czech beer!
Laters!

Snowbie

ECM is better again and consistent which is good. GFS really struggling beyond T+120 to get to grips with anything concrete. I don't think the HP will sink into Europe and bring the S'ly.
I am starting to sway with more N blocking as ECM is constantly predicting. This is better than a Scandi block atm.

Snowaddict

Deleted User wrote: »

Greetings from a rather mild prague.
I see the gfs is acting the maggot with your hopes and desires SA.
None of the regulars on here including me pay the kind of heed you have been to far FI GFS.

Be aware that ,it's either going to end up like jan 2007 with the others following suit and a very weak easterly or we're going to have something good out of this.

Also I'll add that the GFS is poor and always has been from what I'm told in dealing with reverse zonality so it's all up for grabs but again an awfull lot to ask!

I won't be able to look at the models that much if at all over the coming days so who better to ask than yourself to post up summaries for me

In the meantime I must get back to my rather strong czech beer!
Laters!

Well hello Black Briar. I was wondering why you hadn't posted in a few days. I don't think I have paid too much attention to it. Its good to post all aspects, and I have posted ensembles etc... as well as info on the ECMWF. I'm sure they are not only my hopes, I'm sure many on here would love to see a classic cold spell reaching our shores.

I'm not calling it just yet, but I I think it will be safe to call it in another 48 hours. But I will say this, there are several UK forecasters who base the long range forecast on teleconnections and bigger trends, and all of these trends are pretty consistent for a cold to possibly very cold spell beginning just after Xmas and continuing out into the new year. This should be something to bear in mind.

The outputs of the next 48 hours are crucial IMO, and its still all to play for in terms of a cold spell, which IMO could yet produce something quite good or possibly classic.

Hope you enjoy the beers,
SA.

Snowaddict

Snowbie wrote: »

ECM is better again and consistent which is good. GFS really struggling beyond T+120 to get to grips with anything concrete. I don't think the HP will sink into Europe and bring the S'ly.
I am starting to sway with more N blocking as ECM is constantly predicting. This is better than a Scandi block atm.

Indeed Snowbie. I would think its quite possible that GFS operational may come on board again in the next 36 hours. Several of its perturbations have stuck with the ECM type output, which is most encouraging.

I agree the N Blocking modelled is far more favourable, because it does have the potential (only potential) to deliver a classic wintry setup. I would remain quite confident, as I have done for the past 3 -4 weeks in the development of a cold to possibly very cold and possibly wintry evolution post Xmas and out into the new year, however nothing set in stone as of yet, and it could still go either way.

The consistency of the ECM is most encouraging.

Deep Easterly

@BB, hope you're enjoying your beer:P. As much as I dismiss the GFS at times, SA's initial predictions of a cooler spell coming in off the continent a few days ago were based on GFS FI's charts, so I will have to hand the GFS that. Of course I am not one to be convinced about weather possibilities until it is shown by ECM, as GFS will show something remotely right in one run, only to be discredited by a completely different set up 6hrs later.

If the GFS was more consistant between each run even up to 192/240hrs, then I think this model would become equally as credible and respected by model watchers as is the ECM. This is why I stick with the ECM to be honest, as they tend to be more consistant up to this point. Of course it flips and ramps at times too, but less frequently that GFS.

I think the GFS will improve and excel in a few years time though regarding the medium term, so hopefully a model that will be worth looking at in the future.

Danno

Almost every year, it snows on December 29th, my birthday. This year I am going to be 29, I live at house number 29. The signs are in the numbers!

Snowaddict

Well, it sure does look like we will be entering a much colder spell from about next Friday / Saturday... Of course these charts can change, but as I've been harping on about over the past few weeks, it does indeed seem fairly likely now that a colder spell of weather will arrive just after Xmas.

Whether this will produce something significant is still very much uncertain, but it won't be warm by any means next Sat at 12 noon.

JanuarySnowstor

Well il be posting on here a bit more often because my head is fried from Netweather. You cant even mention the word downgrade without getting scowled on - v sad imo.
My take on the whole thing is a dry fairly boring week coming up with little frost as the wind will be too strong. Turning colder ( though no decent upper cold ) from Friday onwards. Anything after Sun is pure FI so doesn't count. In no way is this a proper decent Scandi high and with an Eastern Europe way milder than normal of late little if any proper cold to move East. Maybe closer to New Year things might look more promising but that's 50/50 and it could quite easily be a sinker!