Winter/Spring 2013 (Model Output Discussion)

Su Campu

BEASTERLY wrote: »

Thanks for the last reply, very informative. Why do you believe the strat PV is going to be cranking up @ day 9 or 10? Surely model output for the strat at that timeframe is subject to the exact same FI caveats? And if the models go for blocking while also progging a strengthening strat PV, what does that tell us about the strength of correlation between stratospheric vs tropospheric synoptics?

Both GFS and ECMWF are showing the same thing with the stratosphere. By and large, the stratosphere is much more stable and of a long temporal scale. It's less affected by factors that have more affect in the troposphere, such as terrain, SST, snowcover, etc. so they are therefore more forecastable. I would have a much greater confidence in a strat forecast than a 500 hPa.

With a time lag between strat forcing and the troposphere, any trop block indications for 8-10 days out will most likely be short-lived as the impending PV strengthening within the next week will show its affects in the troposphere soon after the block is progged to set in.

The only thing that could scupper a strat forecast is a SSW, but there is no indication of that happening in the next week or two, so projecting forward it would look like most of the month will most likely be more zonal, albeit maybe interrupted by a brief block of some sort.

John.Icy

ECM ensembles for Holland are....shamazeballs/shamazing.

God such quietness for such lovely charts.

Whether they happen or not, absolutely stunning charts today.

Roll on pub run

nacho libre

so a block has never won out in such a situation. if this is the case, i wonder how did the events of winter of 62/63 happen? surely the stratosphere did'nt stay cold all the time? i'm guessing there must have been a major ssw event that followed on from a split vortex, which might explain why it stayed cold for so long in England.

by the way if a major block takes hold in Scandanavia, could this not lead to an eventual ssw event? are we not overdue a ssw event. so many questions, so little time

Deep Easterly

John.Icy wrote: »

ECM ensembles for Holland are....shamazeballs/shamazing.

ECMWF en mean 500 hPa chart at 240 hrs, this model has been fairly consistent on building that ridge to our north for a good while, whether it verifies or not only time will tell.

BLIZZARD7

Deep Easterly wrote: »

ECMWF en mean 500 hPa chart at 240 hrs, this model has been fairly consistent on building that ridge to our north for a good while, whether it verifies or not only time will tell.

Very very nice ECM ensembles- Coldest run of season by some way. Really happy with the support building for this block and easterly. As things stand its looking like a cold and possibly snowy run up to christmas.



Amazing ECM Mean chart at +240hrs



Let the trend continue!




Dan

ninebeanrows

Pub run poor.

Who knows what is going to happen. I am just concerned about the lack of height rises over Greenland which are often crucial for cold, especially for it make it to Ireland.

Lets hope the ECM Ensembles have this right.

Villain

If you though the GFS pub run was bad don't dare look at 06z, it's worse much worse, Cold is much further East

Tom Cruises Left Nut

Villain wrote: »

If you though the GFS pub run was bad don't dare look at 06z, it's worse much worse, Cold is much further East

It really is a stinker. Ah we are playing the long game here though, January is what I am waiting for and after, the signals look better for then

Caff Caff

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t|nt|n wrote: »

It really is a stinker. Ah we are playing the long game here though, January is what I am waiting for and after, the signals look better for then

Exactly... I don't see the big problem apart from the models showing precisely what we already knew was trending. A "milder" spell coming up to Christmas! This is the yoyo synoptics we've been seeing all year on the models.

I will repeat, considering my last post was removed for some reason, I believe the colder aspect to our winter will be more noticeable at Christmas and the days after with a stronger potential for wintry prec. Although, in saying that, this could all change in two days time, this is precisely what is exciting about the model runs and weather in general. Who knows what the 18z will show later.

pistolpetes11

Post from Ian ferguson from the MET over on NW, I hope we dont get left on the outside looking in again !

Latest from Ops Centre:
" 4. Trend for Days 10-15 : Best estimate is to remain colder than average with frost more widespread than normal and some wintry ppn likely, especially in the N and E. Highest probs of milder, but wetter interludes are towards the W/SW.
5. Discussion : There are major differences between EC and MOGREPS through this period. Initially these differences are not too great, with both ensemble suites having a signal for a brief milder interlude early next week, especially across northern Britain. Thereafter a blocked pattern is expected to develop, but there are large differences between MOGREPS and EC with the detail of the block, with EC ensemble having a strong signal for an E’ly, whilst MOGREPS has a S’ly. NCEP ensemble appears to be roughly split 50/50 E’ly and S’ly. The EC solution has been favoured at the moment, with slightly more support, but with the caveat of occasional frontal incursions into at least in W’ern parts of the UK."

Speak Now

Battleground

catch.23

Jerry Seinfeld wrote: »

Battleground

The problem with battleground is that 9 times out of 10 mild wins, or there is brief wet snow followed by hours of rain.

Speak Now

catch.23 wrote: »

The problem with battleground is that 9 times out of 10 mild wins, or there is brief wet snow followed by hours of rain.

I know thats why i winked :pac:
It's just another long range forecast waiting to go belly up anyway!

Musicman2000

Anyone know when MT'S winter forecast is out? was it out earlier last year?

whitebriar

While Ian fergusons thoughts are hope full for the snowbies,2 caveats..
He's quoting the UK equivalent of NOAA/central Nws brain centre thinking.

If you ever read the scientific discussion from the USNWS( available on underground)- its their version ,except they make it public.
It changes often.

2nd caveat,wales and Sw England are who they're talking about when they say in the west.
We are further west than that


On a positive note,its clear ,like us they just haven't a clue right now beyond t96.
Their intuition, is favouring an easterly though and that's important.
But imho,its just not cold enough way east yet.I said that yesterday.
Scandi highs don't usually stick around for more than 2 weeks without an Atlantic block.
Hence why a milder Xmas does seem plausible in the current set up but would you like to watch this space for round two,the better attempt into 2013?

Let's see.

Elmer Blooker

for the last couple of weeks this is what I've been hoping for - a link up between the Atlantic / Azores high with that huge high to the NE. A great 12z in my opinion.
Not there yet but a step in the right direction.
reminds me of this http://www.wetterzentrale.de/pics/archive/ra/1947/Rrea00119470121.gif

BLIZZARD7

Models are all over the place today, 00z GFS and 06z GFS trended away from an easterly but it is firmly back on the 12z. ECM 00z was very good with very cold emsembles.

UKMO 00z was very poor and the 12z is just a slight improvement, we can still get to an easterly from +144hrs but it would not be the likely option in my opinion. Atleast the shortwave to our north moves south east between +120hrs and +144hrs though.

So all in all we started on dodgy ground but the models seem to be going back to the easterly scenario with some nice eye candy on the GFS 12z. Outlook is very uncertain at the moment But I think an easterly via scandi block is still slightly favoured at present.

Hopefully ECM 12z backs up the latest GFS run.





Dan

Jaffusmaximus

http://metofficenews.wordpress.com/

"Met Office observation systems have picked up a minor SSW in the stratosphere over the past few days, suggesting that this may have an impact on the UK.
Jeff Knight, a Climate Scientist at the Met Office, said: “Satellite and other observation data show that there is a minor SSW going on and this is one factor amongst many others which could perpetuate the colder than average conditions we have seen recently.
“It could take anything from a few days to a few weeks if it is going to have an impact. However, it’s consistent with the current 30-day outlook from the Met Office which favours colder than average conditions – albeit with a fair amount of uncertainty.”
The Met Office will continue to monitor the situation and, as ever, will keep everyone up to date on any periods of cold weather through our forecasts and warnings."

As is above so is below

sully2010

Su has had a hissy fit and closed his account...which is a shame because his posts are usually good apart from the negativity



BANNED FOR A WEEK

Sponge Bob

BLIZZARD7 wrote: »

Models are all over the place today, 00z GFS and 06z GFS trended away from an easterly but it is firmly back on the 12z. ECM 00z was very good with very cold emsembles.

What I am seeing in the models is a flip flop between easterly european air masses and the beginnings of seeing a jet driven sequence of cyclones or bombs punching across from the west. The GFS surprised me with its overall accuracy in December 2011 particularly when it came to forming and moving the sequence of bombs that hit us in mid december early January.

Nothing unusual about sequences of atlantic storms and warm air in their wake and in the period from around the 20th fo December to the 10th of January.

MT has alluded to a hunch of his that something like that may happen although I think he mentioned the 14th or so.

Birdnuts

The current runs are similiar to what happened in Feb this year - epic cold to our East, but our little island just about stays in the mild dross:(!!

pistolpetes11

Sponge Bob wrote: »

What I am seeing in the models is a flip flop between easterly european air masses and the beginnings of seeing a jet driven sequence of cyclones or bombs punching across from the west. The GFS surprised me with its overall accuracy in December 2011 particularly when it came to forming and moving the sequence of bombs that hit us in mid december early January.

Nothing unusual about sequences of atlantic storms and warm air in their wake and in the period from around the 20th fo December to the 10th of January.

MT has alluded to a hunch of his that something like that may happen although I think he mentioned the 14th or so.

Its actually a period Im keeping a close eye on , he has alluded to a wind event around the 12th-14th of this month

M.T. Cranium wrote: »

FURTHER OUTLOOK ... Somewhat milder conditions may follow towards the second week in December in a west to northwest anticyclonic type flow, and my research suggests it could get quite windy around the 12th-14th although the models have not picked up much on that at this time range. There is some hint of this storm going south but would expect that to change.

derekon

I see that Mark Vogan in his forecast today is forecasting that snow and cold will build west from Europe and freeze Britain & Ireland. Looks like we are in for a mild spell so ...................... :D

I am a wee bit bold some of his thoughts are outlined in the forecast link below. However to view the full forecast, you will have to sign up for a monthly subscription. I know, the cheek, especially after his cock up of a forecast for 2011 in the UK and Ireland (Glasgow to reach -20oC and both islands to turn to snow fields)......

Still God loves a trier

D

http://www.markvoganweather.com/2012/12/04/i-stand-by-my-forecast-europe-snowcold-to-build-west-ukireland-to-freeze/

pistolpetes11

Well the 18z has delivered tonight , I have put that charts in the FI cause that what I think they are but things are taking a turn for the good

A good ol easterly on the cards , the cold outcome keeps showing up , its just a matter of the models getting a good handel on it now

Fascinating chart watching

Jaffusmaximus

pistolpetes11 wrote: »

Well the 18z has delivered tonight , I have put that charts in the FI cause that what I think they are but things are taking a turn for the good

A good ol easterly on the cards , the cold outcome keeps showing up , its just a matter of the models getting a good handel on it now

Fascinating chart watching

Wonder if there will be anymore movement west on the block?

pistolpetes11

Its the 18z , its a cracker , its surely set up for downgrades tomorrow so dont get too over excited yet

Villain

Yup a good pub run but it's well into FI before it produces and running it side by side with the 12z it shows the differences aren't huge but the impact is. It will flip and flop a few times before it gets under +96

Sponge Bob

Based on the perennial 06z and 18z flip flops in recent days I forecast the Atlantic in the ascendancy again in either or both of the 06z and 18z GFS tomorrow. Whether the GFS shows a string of bombs is moot.

I'll be back!

Caff Caff

I have to agree. Fantastic run there for the 18z. As I said in my earlier post it could all change in the 18z. Yes, it is somewhat FI but you can see at +72 hr that easterly beginning to work it's way deeper into south west Europe to set up shop. Now, this could recede in the next run but this has been a recurrent trend and the cold does need to build some more in the east before making it's way here, particularly if it wants to take on the Atlantic but in this run it is holding it's own with the jet stream coming down from the north, pulling (I presume) that much needed cold pool. Then a weaking Jet Stream and coming up to 144hr onwards it has broken up. Keep'm coming!

This is why we're all here. Very exciting model runs and yoyo synoptics and I know I'm learning so much from you all so thank you. I still stand by a wintry outlook(some snow showers) becoming more and more likely by the end of this month and into January. Hopefully then it may become more severe by the end of Jan for all snow lovers. By the uncertainty from model runs all year, it could even be slightly earlier.

pistolpetes11

Following Ian fergusons twitter (UK Met meteorologist and weather presenter for BBC)

Anyway someone was have a chat with him , about the 18Z

Ian Fergusson ‏@fergieweather
@MarkyDub you've probably also seen @metoffice comment today on SSW hints. Broad pointers are towards colder E'rly dig into mid-month now.
Expand
23m Ian Fergusson ‏@fergieweather
"@MarkyDub: @fergieweather seen the 18z GFS Ian ?any thoughts" Yeah, the broad easterly component is consistent with EC32 & UKMO outlook


Weathercheck If you join the Irish Met , I want a proper 32 day outlook