Model Output Discussion 26/10 2012 >

[Ice BIast]

What an awful day for the models, although this has coming for the last few days with not a lot of positive reports.

Im not one to rule out the winter altogether, although this doesn't look look for the future with the Nothern blocking being removed.

TBH, I wouldn't be too unhappy with the output from today. Sure, its looking pretty mild in the next couple of weeks, but there is still little sign of a strong PV, and if I understand GP correctly, the heights to the east (If it verifies) could cause wavebreaking in the strat and potentially result in cold later on anyway. I wouldn't get downbeat yet.

[UV-RAY]

Have we not learnt anything over the years regarding Scandi and Russian highs , how many times are they progged to advance at +240 or even +72 only for them to get put back even further. Look NW I would say for any blocking.

[mulzy]

Folks - it's only November 5th - start looking for cold from late November/early December - till then, relax...

[cfallon]

It's the same old story in here lol doom and gloom one week then hysteria the following week! Chill peeps way to early in the season to nail the coffin shut on winter!

[John Badrick]

Folks - it's only November 5th - start looking for cold from late November/early December - till then, relax...

Very, very true, well said

[mcweather]

It's the same old story in here lol doom and gloom one week then hysteria the following week! Chill peeps way to early in the season to nail the coffin shut on winter!

An extremely sensible post. Calling time on anything pre christmas winter wise is ludicrous on November 5th.

Presumably those doing so were doing the same in Nov 09 and November 2010 just because it was abit mild and stormy.

Edited November 5, 2012 by mcweather

[UV-RAY]

Very, very true, well said

We tried that last year.

[UV-RAY]

It's the same old story in here lol doom and gloom one week then hysteria the following week! Chill peeps way to early in the season to nail the coffin shut on winter!

Not many are calling time most are being realistic, I don't think any block will be from the East, not yet anyway. Looking at the models I would say two weeks of normal Autumnal weather really, so a bit of everything. Edited November 5, 2012 by Seven of Nine

[Geordiesnow]

What an awful day for the models, although this has coming for the last few days with not a lot of positive reports.

Im not one to rule out the winter altogether, although this doesn't look look for the future with the Nothern blocking being removed.

But blocking IS there, it just in the wrong place to deliver anything cold for the UK, most of the blocking is occuring over Russia and the models are indicating the high is going to move into the Arctic and not affect any weather patterns around here, at least for the moment.

Unfortunately, the newfoundland high which was projected to attempt some sort of ridge into Greenland has more or less gone now so a flatter pattern is in the pipeline with temperatures around average for the most part. No real mild SW'lies being forecast and certainly no Bartlett high so it could be worse.

One thing to note is just how "mild" in terms of upper air temperatures Russia is going to be compared to recent years, again, this is down to the block that is positioned there at the moment.

Its still early days but compared to October, the northern hemisphere pattern is not one to get overly excited about at this moment in time.

[Frosty.]

It's the same old story in here lol doom and gloom one week then hysteria the following week! Chill peeps way to early in the season to nail the coffin shut on winter!

it's more of a reality check being needed because most if not all of our weather in the next few weeks at least will be coming in off the atlantic, be it ridge but more likely a train load of depressions with our name on it. And you are right, winter is still over 3 weeks away and things could be looking a lot different by 1st December.

[stewfox]

What an awful day for the models, although this has coming for the last few days with not a lot of positive reports.

Im not one to rule out the winter altogether, although this doesn't look look for the future with the Nothern blocking being removed.

That almost counts as a winters over posts and its 5th November. Northern blocking hasn't been removed just a few charts not as good as yesterday and it was only ever potential.

What are we told every day on here, not to latch onto daily charts , seems we have had a wide swing today in the mood due to small changes in the model output at T240 +

Chin up November CET is 2.9c below average at present

[Polar Maritime]

Not many are calling time most are being realistic, I don't think any block will be from the East, not yet anyway. Looking at the models I would say two weeks of normal Autumnal weather really, so a bit of everything.

Agree everything is looking a very Autumnal affair across the models, There's no need to reach for the prozac pills yet with 3+ weeks to go until winter.

[legritter]

Evening all ,im sure that after a fairly quiet spell over the next 5 days or so we will see some interesting weather grace our shores . it does look like high pressure is setting up over eastern europe russia etc . but at the moment going by latest charts and data i dont think it will be close enough to give us a direct hit with any seriouse cold .But im sure it will stop the eastward movement of low pressure systems .It could be the start of a weather change but steady as she goes, mother nature is full of surprises .and going by GFS rainfall forecasts a possibility of high rainfall totals .and we could see low pressure just coming at us constantly [it seems to like us the last 8 months or so ]Perhaps it took some lessons from last yrs AZORES HIGH .so any poster who feels like reaching for the PRozack or throwing the toys out the pram DONT ,We still have 3 weeks of autumn left ,and believe it or not 13 Weeks of winter to come ,and of course followed by March which can also deliver all sorts of goods .time soon for the Gfs , and in the morning after churning out trillions of bits of info we have ECM and UK Met . so enjoy . i hope iv cheered up a few including myself .Must again say a big thanks to the technical posters on NET WEATHER .who would have thought 7 days ago yet alone even last friday that i would be building a snowman for my grandchild last sunday ,WE called it MR slushy ,cheers gang .

[mcweather]

Agree everything is looking a very Autumnal affair across the models, There's no need to reach for the prozac pills yet with 3+ weeks to go until winter.

As indeed it should on November 5th regardless of what winter is to deliver

[Snowman.]

I must say though that the PV doesn't look like its going to stay over greenland that long

[Polar Maritime]

As indeed it should on November 5th regardless of what winter is to deliver

It does this year, but not always.

[johnholmes]

The latest NOAA 500mb anomaly output may give just a hint of hope to cold lovers, I'll post the link in a second.

It continues with its theme over the past 2-3 days, yes weekend included, of showing +ve heights from the far west of USA (Alaska) and far east of Russia around the north pole, (NOT our side as the polar vortex is there) all the way back across into northern Scandinavia and northern Russia. The Atlantic is shown as being fairly strong westerly on the time scale it is valid for, that is 13-19 November, the heights over the UK show little if any sign for the past 5-6 days of rising from the levels shown then, so never all that mild would be the suggestion from that. Fairly unsettled and with the 500mb trough just west of the UK one would expect the risk of a fairly active weather system at some point in that period, possibly more than one. Ahead then temperatures a shade above normal but in the rear of it on the cold side. Just what effect this type of synoptic may have on the over 500mb prediction is hard to second guess.

The MJO is in phase 3 which hadly ties in with what we have at the moment. Neither the AO nor the NAO are predicted to support high level 500mb +ve anomalies but the 500mb anomaly charts all show this.

So far from easy in this time scale, let alone further ahead as chio is posting regarding the effect the Stratosphere may have later on in any possible effect below the Tropopause.

Going back to the 6-15+ day period then I would tend to lean on some kind of blocking beginning to start to affect further south and buckling the upper flow over the Atlantic which would allow colder air in from the NW. If I was a betting man I would side 65:35 with that compared to the idea of the cold coming from between north and north east IN the period I am posting about.That is out to about the 3rd week in November?

Please feel free to disagree or agree but some attempt at justifying your stance would be good for discussion and helping newcomers and visitors to this site.

NOAA link

http://www.cpc.ncep....14day/500mb.php

ECMWF-GFS link

http://www.meteo.psu...0z/hgtcomp.html

enough from me for today

Edited November 5, 2012 by johnholmes

[Cloud 10]

Something 'interesting' for cold synopticians definately beginning to sir now in the extend range for final third of the month / start December.

We have various teleconnectors (principally a poleward migrating +AAM signal and coupled MJO wave) siganlling high latitide block at this time.

Last couple of GFS runs from around mid month onwards starting to hint at split vortex scenario. This includes a split lower stratospheric vortex programmed with lobes centred over Siberia and Canada.

Last 3 CFS runs for weeks 3 and 4 have developed blocking structures over Greenland / Iceland locale, and today forecast is for cross polar ridge.

http://origin.cpc.nc...121104.z500.gif

(note the Kamchatkan ridge / Greenland ridge wavelength there)

I suspect that this is a failry strong signal if both teleconnectors and modelling is consistently picking this.

Tonight's NAEFS looking similar to that week 3 CFS chart with height rises to our North.

In the meantime,good agreement for the continuation of unsettled conditions for the UK,with

a deep trough either over or just to the west of us.

Climate Prediction Center - 8-14 Day 500mb Outlook

ECMWF/GFS DAY 8-10 MEAN 500MB HEIGHT COMPARISON

LOL,John Holmes explained it better!^^^^

Edited November 5, 2012 by Cloud 10

[SMU]

http://modeles.meteociel.fr/modeles/gfs/runs/2012110518/gfsnh-0-114.png?18

Hum is it to late for the models to hit that eastern brick wall

S

[Paul_1978]

Folks - it's only November 5th - start looking for cold from late November/early December - till then, relax...

+1. Far too early to be unduly concerned.

[BLAST FROM THE PAST]

http://modeles.meteo...nh-0-114.png?18

Hum is it to late for the models to hit that eastern brick wall

S

SteveI think that brick wall will be hit, but I don't think until AFTER say 15-17. ECM was interesting to me as initially we saw the LPs crossing the game line but as we approach mid month we see a more southerly trajectory of LPs AND we see the trough core from say t168 stop, shift slightly north then back west. The period to watch IMO, with general 'west' flow up til then becoming southerly.

Edit - re looking for cold, don't look for cold look for the synoptic pattern.

BFTP

Edited November 5, 2012 by BLAST FROM THE PAST

[syed2878]

hi guys this today's prognastic discussion for the u.s side of things and it seems that they favouring the 00z ecm on their 6-8 and 8-14day outlook of course i might be talking crap so here's the discussion.

PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS.

6-10 DAY OUTLOOK FOR NOV 11 - 15 2012

THERE IS GOOD AGREEMENT ON THE PREDICTED CIRCULATION PATTERN FOR THE 6-10 DAY

PERIOD AMONG THE GFS, ECMWF, AND CANADIAN ENSEMBLES. IN LARGE PART THESE

SOLUTIONS SUPPORT THE HIGH-RESOLUTION MODEL RUNS FROM THE GFS AND ECMWF. THE

CONSENSUS IS FOR A HIGH-AMPLITUDE RIDGE EXTENDING FROM JUST SOUTH OF THE

ALEUTIANS THROUGH WESTERN ALASKA TOWARD THE POLE, A TROUGH DOWNSTREAM CENTERED

NEAR THE GREAT PLAINS, AND A RIDGE OVER THE NORTHEAST CONUS AND SOUTHEAST

CANADA. THERE IS GENERALLY LOW TO MODERATE SPREAD AMONG ENSEMBLE MEMBERS OVER

THE CONUS, WITH THE LARGEST SPREAD UPSTREAM CONCERNING THE EXACT POSITION AND

MAGNITUDE OF THE POSITIVE HEIGHT ANOMALIES CENTERED NEAR WESTERN ALASKA.

THE FORECAST CIRCULATION PATTERN OVER AND NEAR NORTH AMERICA IS DOMINATED BY A

NEGATIVE PNA PATTERN AND THE PNA INDEX IS FORECAST TO REMAIN NEGATIVE THROUGH

WEEK TWO. IT IS ALSO NOTEWORTHY THAT THE POSITIVE HEIGHT ANOMALIES EXTENDING

FROM THE NORTH SHORE OF HUDSON BAY TOWARD ICELAND ARE FORECAST TO DISAPPEAR

DURING THIS PERIOD. AS SUCH, THE AO IS FORECAST TO BE POSITIVE DURING THE

PERIOD WITH HIGH UNCERTAINTY BEYOND DAY 10.

THE NEGATIVE HEIGHT ANOMALIES CENTERED OVER THE GREAT PLAINS RESULT LARGELY

FROM AN INTENSE TROUGH THAT PROGRESSES THROUGH THE AREA IN THE EARLY PART OF

THE PERIOD, FAVORING BELOW NORMAL TEMPERATURES. THE RIDGE DOWNSTREAM NEAR THE

EAST COAST FAVORS ABOVE NORMAL TEMPERATURES OVER MOST OF THE EASTERN THIRD OF

THE CONUS WITH THE EXCEPTION OF THE FLORIDA PENINSULA, WHERE NEAR TO BELOW

NORMAL HEIGHTS AND EASTERLY FLOW SHOULD KEEP TEMPERATURES NEAR NORMAL. POSITIVE

HEIGHT ANOMALIES FAVOR ABOVE NORMAL TEMPERATURES IN NORTHERN AND WESTERN

ALASKA, WHILE THE SOUTHEASTERN PART OF THE STATE SHOULD SEE BELOW NORMAL

TEMPERATURES.

ABOVE MEDIAN PRECIPITATION IS FAVORED FROM THE CENTRAL GULF COAST NORTHWARD TO

THE GREAT LAKES AHEAD OF THE TROUGH CENTERED TO THE WEST. ABOVE MEDIAN

PRECIPITATION IS ALSO FAVORED ACROSS THE NORTHERN ROCKIES AND NORTHERN PLAINS

DUE TO BOTH THE LARGE STORM SYSTEM EXPECTED EARLY IN THE PERIOD AND APPROACHING

SHORTWAVES EMBEDDED IN THE MEAN FLOW. ENHANCED PROBABILITY OF BELOW MEDIAN

PRECIPITATION IS FORECAST IN THE SOUTHWEST DUE TO NORTHWESTERLY FLOW BEHIND THE TROUGH CENTERED FURTHER EAST.

TODAY'S OFFICIAL 500-HPA BLEND CONSISTS OF 20 PERCENT OF TODAY'S 0Z GFS

ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN

CENTERED ON DAY 8...20 PERCENT OF TODAY'S OPERATIONAL 0Z ECMWF CENTERED ON DAY

8...30 PERCENT OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 10

PERCENT OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8.

MODEL OF THE DAY: 00Z ECMWF ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO

GOOD MODEL AGREEMENT PARTIALLY OFFSET BY MODEST DISAGREEMENT AMONG FORECAST

TOOLS AND THE INHERENT UNCERTAINTY PRESENT IN A MODERATELY PROGRESSIVE PATTERN.

8-14 DAY OUTLOOK FOR NOV 13 - 19 2012

THE CIRCULATION PATTERN FOR THE 8-14 DAY PERIOD IS LESS AMPLIFIED OVER THE CONUS COMPARED TO THE PRECEDING 6-10 PERIOD, WITH A BROAD TROUGH FORECAST OVER

THE ENTIRE CONUS. THE ECMWF AND GFS ENSEMBLES ARE IN GOOD AGREEMENT ON THIS

POINT. THE RESULTING HEIGHT PATTERN CONSISTS OF WEAK NEGATIVE HEIGHT ANOMALIES

CENTERED IN THE PACIFIC NORTHWEST AND POSITIVE HEIGHT ANOMALIES CENTERED IN

SOUTHEASTERN CANADA. VERY WEAK ANOMALIES EXIST ELSEWHERE OVER THE CONUS. THE

MEAN RIDGE POSITION OVER THE NORTH PACIFIC IS CENTERED SLIGHTLY FURTHER WEST

THAN IN THE 6-10 DAY PERIOD.

ABOVE NORMAL TEMPERATURES ARE FAVORED IN THE SOUTH-CENTRAL CONUS DUE TO

SLIGHTLY HIGHER HEIGHTS THERE. THIS AREA OF ABOVE NORMAL TEMPERATURE EXTENDS

INTO THE NORTHEAST WHERE 500-HPA HEIGHTS REMAIN ABOVE NORMAL. BELOW NORMAL

TEMPERATURES ARE FAVORED FROM SOUTHEASTERN ALASKA TO THE PACIFIC NORTHWEST AND

NORTHERN GREAT PLAINS WHERE HEIGHTS REMAINS BELOW NORMAL. NEAR NORMAL

TEMPERATURES ARE FAVORED IN THE SOUTHEAST WHERE HEIGHTS ARE NEAR NORMAL AND THE

SURFACE FLOW TAKES ON A NORTHERLY COMPONENT AS COMPARED TO THE 6-10 DAY PERIOD.

ABOVE MEDIAN PRECIPITATION IS FAVORED ACROSS MOST OF THE NORTHERN TIER OF THE CONUS DUE TO STORM SYSTEMS RIDING THROUGH THE MEAN FLOW IN THE WEST AND

SOUTHWESTERLY FLOW ON THE WEST SIDE OF THE RIDGE TO THE EAST. BELOW MEDIAN

PRECIPITATION IS FAVORED IN THE SOUTHWEST AS THE STORM TRACK SHOULD REMAIN TO

THE NORTH OF THAT REGION.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 20 PERCENT OF TODAY'S 0Z GFS

ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN

CENTERED ON DAY 11...AND 60 PERCENT OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN

CENTERED ON DAY 11.

FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: ABOUT AVERAGE, 3 OUT OF 5, DUE

TO GOOD MODEL AGREEMENT, OFFSET BY UNCERTAINTY PRESENT IN A LARGELY ZONAL FLOW.

FORECASTER: STEPHEN BAXTER.

http://www.cpc.ncep.noaa.gov/products/predictions/610day/fxus06.html

[SMU]

SteveI think that brick wall will be hit, but I don't think until AFTER say 15-17. ECM was interesting to me as initially we saw the LPs crossing the game line but as we approach mid month we see a more southerly trajectory of LPs AND we see the trough core from say t168 stop, shift slightly north then back west. The period to watch IMO, with general 'west' flow up til then becoming southerly.

Edit - re looking for cold, don't look for cold look for the synoptic pattern.

BFTP

HI Fred- Im not happy with the current output- doesnt feel right.

expect change tomorrow.

S

[Swave Snow]

I think you are right Steve, i hope its an upgrade for us deep snow lovers, but some believe things are looking much less blocked lets hope things are more blocked

[BLAST FROM THE PAST]

HI Fred- Im not happy with the current output- doesnt feel right.

expect change tomorrow.

S

Hi Steve

It was similar to 2 days ago and was better yesterday, i agree that its far from settled

BFTP