Winter/Spring 2013 (Model Output Discussion)

Duggys Housemate

yeah fersuson seems certain of a cold December for Britain, even the south west. Which is still east of most of us.

TheMilkyPirate

Some nice agreement between some models at 192hrs with a scandi high

GFS


ECM


JMA


BOM


NOGAPS and GEM having none of it.

My fave chart from the 18z tonight



:pac:

Sponge Bob

Yeah but they are all 10 days out(ish) Baraca. Thats what the FI thread is for.

Will you post the real charts in 10 days time or will I have to do it for you ??

TheMilkyPirate

Sponge Bob wrote: »

Yeah but they are all 10 days out(ish) Baraca. Thats what the FI thread is for.

Will you post the real charts in 10 days time or will I have to do it for you ??

I know but it's still interesting to see them agreement so far out. Only realised afterwards I should have put it there, Can ya move it PP?

You can post them SpongeBob, Hopefully they will resemble something like above.

Elmer Blooker

baraca wrote: »

ECM 240hr chart is fantastic, FI but hey it shows what could happen in a set up like this.

Above 240 chart posted on Nov 27th

Caff Caff

Elmer Blooker wrote: »

Above 240 chart posted on Nov 27th

And this is what is showing now. It is not so much a complete easterly but it is aided by that pool from the north would do nicely.

TheMilkyPirate

Elmer Blooker wrote: »

Above 240 chart posted on Nov 27th

Didn't have as much backing as the runs above, Plus was another two days away. I also pretty much said it wasn't going to happen.

Redsunset

For what it's worth I think a Scandinavian high is fairly nailed but it's positioning is crucial for the correct angle of attack of coldest airmass to draw from. There isn't any great cold air over the continent to give a massive difference between upper air and sea temps to create exploding convection. Pressure could also remain too high.

In saying that some lying snow is about now there and it should start to become much colder.
A Greenland high looks very plausible from retrograde of Scandinavian high.

Nothing amazing yet but certainly an improvement. An awful lot needs to go to plan and we have been here before.

snaps

First snow of the winter for London and south east England this morning. So close yet so far. Its always amazed me the difference in the climate between here and south east England.

kstand

snaps wrote: »

First snow of the winter for London and south east England this morning. So close yet so far. Its always amazed me the difference in the climate between here and south east England.

I'm sitting at my desk right across from London Bridge station and we havent had snow in the city this morning.
There was however snow in some of the outskirts - nothing to write home about though in spite of the mild hysteria on the Sky News website.

ZX7R

Looks like MT see something coming out of the east

Villain

Loved the Eagles ending to his forecast on Radio 1 this morning:

"after the weekend it looks like it turn Easterly, and we all know what that can mean, but uncertain at this point"

Harps

Charts this morning are as good as you could hope for for anyone looking for an easterly, a massive 1050hPa high spreading across the whole north Atlantic drawing in cold air from as far east as the Caspian Sea

Still massive uncertainty though despite the broad agreement across this mornings runs.

850hPa ensemble for Dublin shows a lot of uncertainty from the 10th onwards with roughly a 60/40 split in favour of an easterly winning out



Spread shows no agreement whatsoever over what happens over Greenland/Iceland

M.T. Cranium

Signals are improving for wintry episode (more developed than this recent marginal stuff) setting in around Wed 12th and potentially lasting towards Christmas. The depth of cold appears to be in the range needed for snow and at times the maps have fairly promising gradients and synoptics, so at this admittedly long range would say we are now for the first time seeing a better than 50-50 chance of wintry weather from the whole model consensus. I would not say this looks quite as intense as first part of the Nov-Dec 2010 outbreak and I expect it to be the first of several attempts that might get more powerful later in the season. My suggested quote would be "potential for accumulations of snow in parts of eastern Ireland and on hills further west" and not speculating about amounts yet, some of the maps have the look of a few cms anyway.

Main question now is whether successive model runs will develop this theme or back away from it as they did about a week ago, looks a bit more plausible this time. First snow at low levels around 12th?

Tom Cruises Left Nut

Thanks for the update MT :pac:

The 12z runs today will be interesting, we need to see things moving into the reliable timeframe. Once I see something at +72 ill probably lose it !

Anyway, nearly time for the 06z GFS

Elmer Blooker

perfect!! and the GFS very similar, both have LP in the Iberia area and this was what I was harping on about last week when I said we needed to have low pressure in that general area to even get a sniff of a cold spell.
We missed the euro freeze last winter because the Azores high remained too strong.
(PS. loved Villian's post about the Eagle's forecast this morning, Gerry Murphy must be getting nightmares!)

pistolpetes11

t|nt|n wrote: »

Thanks for the update MT :pac:

The 12z runs today will be interesting, we need to see things moving into the reliable timeframe. Once I see something at +72 ill probably lose it !

Anyway, nearly time for the 06z GFS

But in the meantime feel free to ply the FI thread with lots of eye candy delights

Tom Cruises Left Nut

pistolpetes11 wrote: »

But in the meantime feel free to ply the FI thread with lots of eye candy delights

Ha, I do like doing that !

Rebelbrowser

Villain wrote: »

Loved the Eagles ending to his forecast on Radio 1 this morning:

"after the weekend it looks like it turn Easterly, and we all know what that can mean, but uncertain at this point"

Heard him. nearly crashed the car with delight!

Tom Cruises Left Nut

06z time, hoping for a belter

Tom Cruises Left Nut

Possibility of something for parts on Friday ?

leahyl

M.T. Cranium wrote: »

Signals are improving for wintry episode (more developed than this recent marginal stuff) setting in around Wed 12th and potentially lasting towards Christmas. The depth of cold appears to be in the range needed for snow and at times the maps have fairly promising gradients and synoptics, so at this admittedly long range would say we are now for the first time seeing a better than 50-50 chance of wintry weather from the whole model consensus. I would not say this looks quite as intense as first part of the Nov-Dec 2010 outbreak and I expect it to be the first of several attempts that might get more powerful later in the season. My suggested quote would be "potential for accumulations of snow in parts of eastern Ireland and on hills further west" and not speculating about amounts yet, some of the maps have the look of a few cms anyway.

Main question now is whether successive model runs will develop this theme or back away from it as they did about a week ago, looks a bit more plausible this time. First snow at low levels around 12th?

Thanks for that update MT - just a shame you only mention Eastern areas and hills as having possible potential for snow

munsterlegend

leahyl wrote: »

Thanks for that update MT - just a shame you only mention Eastern areas and hills as having possible potential for snow

Eastern areas will certainly be more favoured at first if it materialises but MT also mentioned more widespread snowfall! keep the faith! we got snow from a system that came up the south/south east a few years ago so once we get the cold here who knows what will happen!

Speak Now

Still all FI at this stage really, the south easterly clearing of the low pressure on Monday will decide! Lets hope the high doesn't sit to near us after.

maquiladora

Jerry Seinfeld wrote: »

Still all FI at this stage really, the south easterly clearing of the low pressure on Monday will decide! Lets hope the high doesn't sit to near us after.

Not the most encouraging ensembles. Op & control are colder than many of the ensembles on the important days, at times they are the very coldest. The mean never gets any colder than it is at the moment. Downgrades highly possible on forthcoming op runs there.

Still too far away to be looking at details closely though. We'll see how things look in 48 hours. I wouldn't be getting excited yet.

Tom Cruises Left Nut

Some thoughts from Glacier Point over on NW

To add to the positively cold vibe going on....

The trend for vortex shift towards Siberia gathers apace. This should assist in retrogressing the ridge over Scandinavia towards Greenland in the extended range. GEFS mean hight anomalies depicting an amplification of the North Pacific ridge which teleconnects to height rises over southern Greenland.

The only complicating factor remains the modelling of a cut off section of the pv over NE Siberia and its movement across the North Pacific.

Tom Cruises Left Nut

Ill take the control run

maquiladora

12Z ECM looking bitter at 168.

A lot can change in 7 days though.

ninebeanrows

ECM is a stonker. Let's hope this is the real deal.

Big positives are the main change is occurring at T96hrs which is heading into very well modelled timeframe!

Don't order the toboggan just yet, ahhhhhhhhh sure go for it

Tom Cruises Left Nut

Weathercheck wrote: »

ECM is a stonker. Let's hope this is the real deal.

Big positives are the main change is occurring at T96hrs which is heading into very well modelled timeframe!

Don't order the toboggan just yet, ahhhhhhhhh sure go for it

Its a thing of beauty, want to see the last frames now !

Bye bye exams :pac: