Model Output Discussion 26/10 2012 >

[chionomaniac]

Right folks.

New thread - usual rules apply. Keep on topic and no posting junk when you think the mods and hosts have gone to bed!

Will November be cool and zonal or will blocking reassert itself? Here is the place to speculate.....

[NorthNorfolkWeather]

Well, after a brief flirtation with the UK, the 528 dam line heads east and doesn't return in a reliable time frame.

On the other hand, the 546 dam line is well south of us throughout the same period, with some strong indications of wet blustery weather although thankfully that monster low seems to have been significantly downgraded, but the winds mostly from a West or North westerly direction.

So cool, showery, wet in the North and North West, a rather more traditional ( i.e. before 1980) feel to late October/ early November

[Geordiesnow]

Yep quite a mixed bag on offer with bands of rain with sunshine and showers in between any weather fronts and even some gusty winds at times. Also to note with those low thicknesses, then there is bound to be alot of sea convection heading into some western facing coasts so quite an autumnal look with the output but an interesting one, much more interesting than this week's weather for sure.

Its also good too see our side of the Arctic projected to cool down properly now so if we do get another Arctic Northerly, hopefully the uppers will be colder.

[NorthNorfolkWeather]

Yep quite a mixed bag on offer with bands of rain with sunshine and showers in between any weather fronts and even some gusty winds at times. Also to note with those low thicknesses, then there is bound to be alot of sea convection heading into some western facing coasts so quite an autumnal look with the output but an interesting one, much more interesting than this week's weather for sure.

Its also good too see our side of the Arctic projected to cool down properly now so if we do get another Arctic Northerly, hopefully the uppers will be colder.

We need some cold air over the North sea for a while as well, looking at the forecast SST's the southern North Sea is still will over 11C throughout the high definition part of the run.

And looking at the SST's in th low res shows why the low res is ALWAYS FI

[wolvesfan]

Morning all,

Heights remaining strong to our NW on this mornings runs,NAO still -ve,and the tropospheric vortex still dissplaced,no surprise then for a continuation of the cold/cool weather to continue over the UK.

Heights also forecast to rise over Russia,it'll be interesting to see if it has any bearing on the UK weather as November progresses,wonder what the chances are of a Greenland/Russian link up?.

[NorthNorfolkWeather]

Morning all,

Heights remaining strong to our NW on this mornings runs,NAO still -ve,and the tropospheric vortex still dissplaced,no surprise then for a continuation of the cold/cool weather to continue over the UK.

Heights also forecast to rise over Russia,it'll be interesting to see if it has any bearing on the UK weather as November progresses,wonder what the chances are of a Greenland/Russian link up?.

Steve Murr's comments at the end of the last thread suggests that we ought to be looking in that direction (Siberia) in the next 10-15 days. We'll see how that pans out

Edited October 26, 2012 by NorthNorfolkWeather

[Adam lufc]

Has the system moved somewhat east on this run.

[bluearmy]

just looking at the charts for fri/sat and wondered if those congratulating gfs on Monday have any comment. Undoubtedly the euros were backing the trough too far west, but gfs was too far to the east with the ridge. Middle ground wins the day again!

[phil nw.]

Much colder air now moving south across the UK which at least clears that continental murk that some of us have endured the last few days.

So a short cold snap with a frost tonight likely for many especially inland where skies look to remain clearer.

Less cold air with some cloud and rain will already be moving into Scotland later Saturday though, gradually extending south and east through Sunday,so any frost Saturday looks likely to be restricted to more southern areas.

This next system heralds the start of what could be a couple of weeks of quite unsettled and sometimes windy conditions with temperatures close to or just below normal.

I note the pressure anomolies on the 0z NAEF`s and ECM Mean outputs both indicate this troughing around the UK and NW Europe out to day10.

Looking at the fax for today and the one for Monday we can see how quickly things can change once those Greenland heights fade away.

A view of the ECM00z at T144hrs shows the UK firmly entrenched within an upper trough giving us those unsettled conditions going through next week.

It`s still noticeable that although the vortex is still somewhat disorganised the AO index on the overall model ens graph warns of lower heights across the polar regions as we enter November.

It doesn`t necesaary mean we go mild later on, as long as that vortex remains somewhat disorganised pushing the PFJ further south then we can still get brief colder shots but because of less blocking and a more mobile outlook these will be transient.

[shotski]

Signs of a slight rise in pressure over scandinavia perhaps on this mornings ECM at t-168 ?

Could this be something to keep an eye on.

Sorry can't post chart for some reason

[AWD]

The 06z GFS produces a rather notable storm over the UK in just under a weeks time;

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=150&code=code&mode=0&mode3h=0&runpara=0&carte=1

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=150&code=code&mode=0&mode3h=0&runpara=0&carte=0&

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=150&code=0&mode=5

Strong to gale force winds for many there, along with heavy rain.

[Mark Neal.]

The 06z GFS produces a rather notable storm over the UK in just under a weeks time;

http://www.meteociel...npara=0&carte=1

http://www.meteociel...para=0&carte=0

http://www.meteociel...0&code=0&mode=5

Strong to gale force winds for many there, along with heavy rain.

Yes, something which the models have been showing for days on end now is a very notable strong storm heading our way for end of October and start of November.. While a lot of the model watchers I'm sure are glued to where we go next after this cold spell and thereafter, its interesting to say the least that next week could be very wet and very windy. Infact over the next 7 days, it looks very windy and some strong winds, not pleasant and very autumnal like. Also of note the temperatures will be suppressed so it will feel very unpleasant.

This weather which are experiencing its better than surely having days upon end of dull and mild conditions, which has been awful. At least the models look to be correct, because since the beginning of the week they were showing a decent sunny day for most on Saturday, it might be alot colder, but at least the sun will be out.

Mark.

[Jimmyh]

what interests me most is the line of the storms seem to take now. nw to se much different from the heralded 90's of sw to ne interesting that we have not had a notable sw to ne storm for a while

[Frosty.]

Taking a look at the latest ens mean from gfs and ecm, they both look very similar at T+144 hours with a deep trough sat on top of the uk with strong winds and areas of persistent rain alternating with brighter, showery weather and temps generally below the seasonal average with an ongoing risk of snow on the higher hills in the north, the trend towards T+240 hours is for the trough to eventually make some eastward progress to the north of scotland with rather colder air allowed to flow down across the uk, the gfs mean speeds up this process but the ecm mean is continuing to look very unsettled even by the end of it's run, the gfs shows an atlantic ridge moving in, at least across southern britain and that is the signal for pressure to generally rise across the southern half of the uk in the extended range with milder Tropical Maritime air replacing the rPm/Pm airmass, the position of the high probably means it could be rather cloudy but with some breaks in the cloudsheet further east allowing some pleasant sunshine but by the end of the gfs 06z ens mean, the high is shunted away southeast with more low presure moving in from the northwest.

Edited October 26, 2012 by Frosty039

[Nick F]

Be interesting to see how Hurricane Sandy influences the position of the blocking high over Sern Greenland/NW Atlantic/NE Canada - as it drifts NNW across NE USA/NE Canada next week. Obviously the positioning of the block will have a knock-on effect downstream on the position of the trough that will likely govern our weather through next week and perhaps beyond.

The HPC extended forecast suggests uncertainty over Sandy's track and thus below average certainty for the pattern across the NE N America:

			GENERAL FLOW PATTERN
			====================
			A RETROGRADING POSITIVE ANOMALY MOVING FROM SOUTHERN GREENLAND
			INTO NORTHERN QUEBEC FAVORS A QUASI-STATIONARY DEEP CYCLONE NEAR
			THE NORTHEAST, IN THIS CASE HURRICANE SANDY AND ITS POST-TROPICAL
			REMAINS. OTHERWISE...RIDGING IS GENERAL EXPECTED OUT
			WEST...THOUGH QUASI-ZONAL FLOW ACROSS THE PACIFIC IS EXPECTED TO
			SEND ENERGY ACROSS THE NORTHWEST. THE GUIDANCE IS IN EXCELLENT
			AGREEMENT ON THE GENERAL FLOW PATTERN, THOUGH LARGE DETAIL ISSUES
			REMAIN WITH SANDY'S FUTURE COURSE AND STRENGTH, KEEPING CERTAINTY
			IN THE PATTERN ACROSS THE NORTHEAST BELOW AVERAGE.

http://www.hpc.ncep....php?disc=pmdepd

Edited October 26, 2012 by Nick F

[legritter]

The 06z GFS produces a rather notable storm over the UK in just under a weeks time;

http://www.meteociel...npara=0&carte=1

http://www.meteociel...para=0&carte=0

http://www.meteociel...0&code=0&mode=5

Strong to gale force winds for many there, along with heavy rain.

this could be a very interesting spell of weather to start November off . and with some cold air being brought with it again some wintry mix ,but still subject to change at this range .i still feel as i posted recently i wouldn,t be surprised to see lows further south and east providing the high over greenland doesnt weeken too much .and with next weekends generall patern if it materialises as the GFS is modelling, could come with some very quick developing situations .but all modells at present giving plenty of rain and typically autumnal conditions .will be interesting to see tonights ECM 168 Hr chart to see what is given to greenland regards pressure .well here we are OCT 26TH ,And we have air of Arctic origin ,if you like it milder as some do ,you dont have long to wait ,Its good old UK something for all ,cheers all

[Gavin P]

Hi everybody,

Here's todays model based video: Some Unusual Patterns Emerging (And A Look At Hurricane Sandy)

http://www.gavsweathervids.com/

Certainly hints of The Beast waking up early from its slumber.

But no more than that at the moment

[EML Network]

Hi everybody,

Here's todays model based video: Some Unusual Patterns Emerging (And A Look At Hurricane Sandy)

http://www.gavsweathervids.com/

Certainly hints of The Beast waking up early from its slumber.

But no more than that at the moment

Awesome Video as always Gavin.

Looking like it could be a very windy halloween for both the states and also parts of the UK next week...ever since September this year we've been seeing some really unusual patterns globally, I can't help but wonder if the Ice melt has got something to do with this somehow ??

does seem like a bit of a co incidence ?

[Gavin P]

Thanks EML.

We've tended to see rather volatile weather patterns in our part of the world since 2007, but globally its much harder to pin down that is "normal" and what isn't.

[Zenarcher]

Sorry don't have time today for a full 24 hour model comparison but I will compare the ECM since it looks the most interesting at the moment,

1st November,

Yesterday

Today

High pressure to the far East is the most notable change and this pushes everything West.

2nd November,

Yesterday

Today

Very large changes today with the pressure rising more over the East and North.

It will be interesting to see if any other models follow the ECM later today.

[Cheshire Freeze]

GFS 12z saying yes to a marginal rain/sleet/snow 'event' towards the end of hi res....

Perhaps the first signs of GFS picking up on an easterly, as some have touted as perhaps likely to occur within the 14 day period

Edited October 26, 2012 by CreweCold

[pyrotech]

In to Fi and cold lovers must love that chart from the GFS at 192hrs. An under cutting low mixing with cold upper air and ideal thickness. With evaporative cooling those charts look interesting, but at that timescale nothing more than that.

The way GFS gets there does look realistic, but we all are aware of the false hope this one run can give.

Its nice to see, but a few more runs from the models are required, and even if agreement is reached we know how much the details can change even a few hours before.

A few runs thou and it will be mayhem on here.

[phil nw.]

That`s one sharp trough with energy heading right down to Iberia and the Canary Islands next week.

Here at T144hrs GFS12z.

A lot of disturbed weather around for NW Europe and the UK - and for those Islands much further south too

The pattern is perhaps not a snow lovers dream but interesting sypnotically with cold polar air being ejected well south in the Atlantic towards quite low latitudes.

[Cheshire Freeze]

A side note on GFS 12z.....Trough is slightly less deep and so the 528 dam is able to infiltrate the country due to less mixing. Taking the 12z at purely face value, 528 Dam ~ -4 uppers and light winds in trough centre suggests the risk for night time evaporative cooling is there. I'm not saying this is in any means likely but there is potential (on this run) for a surprise snowfall somewhere this coming week.

Believe it or not this synoptic set up brought brief back edge snow on the morning of 31st Oct 2000. I remember it vividly because it was the day Morrisons in Crewe opened- Diane Oxberry also mentioned it on local BBC weather...

Edited October 26, 2012 by CreweCold

[legritter]

Im eagerly awaiting the ECM should be interesting .but at the moment just concentrating out to about 168hRS . Iv taken account of the GFS from this afternoon but not getting to excited yet, as we have been there before but it does look possible with the current pressure around greenland and the current predicted JET Streem .the next 3 runs of GFS needs to be in agreement out to about 144 /168 Hrs .a very interesting time from next wed onwards with what looks to be a very potent autumnal spell of weather with cold air not that far away .and we now have the Possibility in the outlook according to charts of high pressure to our far east so im sure the computer modells will vary greatly from each run .certainly we are not very often in this type of synoptic situation in late October .just one point to new posters and beginners [read all posts and look into the learning area ]and dont forget we have 13 Weeks of Winter to come and still 5 weeks of autumn.and enjoy .