Model Discussion And Chat 19th Feb.2012

[phil nw.]

interesting variation between naefs and ecm ens at day 10

ecm, as per its recent ops has a trough digging to our east. naefs shows a propensity to ridging. latest cpc charts appear to favour the troughing though a little less progressive than the ecm solution.

Troughing would appear the way to go BA.

CPC 500hPa forecast and MJO forecasts seem to agree on continuing low heights to our north.

MJO now in phase 3 soon to move into phase 4 with it`s composite along with the cpc outlook here.

Take those along with the mean hts from the operational runs

A pretty solid agreement for an ongoing +NAO pattern,maybe a more unsettled picture into week 2 with a stronger westerly flow as low pressure comes further south at times.

[bluearmy]

Troughing would appear the way to go BA.

CPC 500hPa forecast and MJO forecasts seem to agree on continuing low heights to our north.

MJO now in phase 3 soon to move into phase 4 with it`s composite along with the cpc outlook here.

Take those along with the mean hts from the operational runs

A pretty solid agreement for an ongoing +NAO pattern,maybe a more unsettled picture into week 2 with a stronger westerly flow as low pressure comes further south at times.

whilst i see the evidence phil, my experience is that ecm can be prone to swings on odd runs. (though not this evening). naefs is generally very consistent, run to run. we dont normally see such a variance at day 10 unless its an obvious rogue run from one of the models. (naefs is made up of two separate data sources though). lets see what tomorrow brings but with T240 ens output, the models should come back into line with each other quite quickly.

[cooling climate]

Troughing would appear the way to go BA.

CPC 500hPa forecast and MJO forecasts seem to agree on continuing low heights to our north.

MJO now in phase 3 soon to move into phase 4 with it`s composite along with the cpc outlook here.

Take those along with the mean hts from the operational runs

A pretty solid agreement for an ongoing +NAO pattern,maybe a more unsettled picture into week 2 with a stronger westerly flow as low pressure comes further south at times.

At the end of the day they are just a forcast no more no less and I certainly would not hang my hat on them.

Of course you can cherry pick CPC runs and mean heights from a week or two back to find varification for

what is being shown now or any other time frame as is being posted in the anomaly charts thread.

But in my opinion they can at times be just as wrong as the model outputs we view.

P.S. I am not saying this is what you are doing by the way in the post I have quoted.

Edited March 1, 2012 by cooling climate

[Geordiesnow]

the ridge thrown up to our ne is progged by most models to make a lot of progress across the hemisphere with a fair amount of WAA headed into the arctic. i think this is going to cause the modelling some headaches over the next few days. all the models have an impressive rise in heights well to our ne stretching across towards n siberia by day 6. expect the unexpected as far as the output is concerned is that verfies.

Just ashame all that will probably be quite fruitless in the end as the PV is very strong and will not budge one little bit, another thing I seem to notice when the models start predicting these WAA going into the Arctic is that it breaks down into lower heights across Svalbard much quicker than the models always indicates and with the strong PV over Greenland, it would not surprise me if this happens again.

The only uncertainty in the model output at the moment it seems is the detail of what will happen this weekend regarding this trigger low that leads to that very brief NE'ly, the ECM seems a little bit on its own at the moment with the positioning and strength of the trigger low.

[nick sussex]

The GFS 18hrs run is in a hurry to sink the high, marked differences between it and the other models with it dropping heights over Svalbard and no sign of any trough disruption.

But its the GFS and given the rest of the output and its recent poor performance then hardly worth reading too much into it.

[johnholmes]

Of course you can cherry pick CPC runs and mean heights from a week or two back to find varification for

what is being shown now or any other time frame as is being posted in the anomaly charts thread.

But in my opinion they can at times be just as wrong as the model outputs we view.

CC that is unfair and an unjustified comment as what I am trying to do is be impartial and show what the 500mb anomaly charts are predicting then show what the 500mb chart actually showed. Nothing 'cherry picking' whatever in that. The dates(they vary due to the 8-14 day NOAA not being for a specific date) but are normally set for the date given on the ECMWF-GFS issue unless I have a pc problem that prevents this..

The only item that is open to discussion, and again its not cherry picking, is my summary from the 500mb anomaly prediction of what that may mean for the weather at the surface over the UK?

Of course they can be wrong-the whole object of the thread is to see how wrong or right they are over many months-how on earth can that be cherry picking?

Edited March 1, 2012 by johnholmes

[summersnow]

_{After a brief colder interlude at the weekend,} GFS _{re-estblishes the Azores HP with a vengeance. Maybe it's here to stay!}

[Timmytour]

Tweet from Ian Ferguson...

V interesting Sunday. UKMO currently go for deeper low as they assess "GFS has not captured initial conditions correctly". Much uncertainty.

[Brum Watcher]

GFS Ens are very very poor in terms of reliable time frame. as early as 48 hours the difference is huge. shocking no idea where to go with them. a spike here a spike there a spike everywhere. looks like an earthquake reading more than anything else.

[Snowy Easterly]

shame hardly no one is up to see this chart, probably the best chart i have seen for march - 16 uppers in mid march

just a fantasy though and won't happen

http://modeles.meteo...11-0-276.png?18

Edited March 2, 2012 by Snowy Easterly

[IDO]

The 0z GFS and the ECM show a very short cool spell with little wintry weather and then the Azores High is dominant right through to the end of FI (18th March). The only saving grace is that the Op run is in the milder cluster. However the way this winter has gone it seems long odds for the UK to get anything cold before next winter. Every ten days a cold spell is modelled and every time it is a blink and you will miss it event. The lack of viewers suggest many members now realize that this is the story of this winter and no amount of strat warming is going to help; other variables are just too dominant.

The truth is out there and the stats don't lie, its been a great end of winter for cold, that is, if you are based on the European mainland!

[Frosty.]

The latest models show a risk of snow showers and frosty nights across scotland on sunday and a spell of very wet and windy weather spreading east across southern and especially southeast england which is good news for the drought hit areas but not good for outdoor plans. High pressure then builds in from the northwest for monday although the southeast looks chilly with nely winds and outbreaks of showery rain only slowly petering out. Tuesday shows the anticyclone being pushed away southeast as pressure falls to the northwest with gale force and milder swly winds with a spell of rain spreading from the northwest and then colder and showery across northern britain midweek with snow on hills, another spell of wet and windy, milder weather following and then colder and showery across the far north by next friday, this is where the gfs and ecm 00z go their seperate ways, the gfs 00z shows high pressure to the south of the uk spreading north and turning the weather settled for all areas with sunny days and frosty nights but the ecm 00z keeps the high further south although the jet is pushed north and the uk is stuck in a strong but mildish westerly flow, occasionally colder in the far north but at least the ecm ends with the jet tilting more nw/se which gives a good chance of colder incursions spreading southeast.

Edited March 2, 2012 by Frosty039

[Zakos]

Perhaps this is why people are "looking for cold". http://modeles.meteociel.fr/modeles/gfs/runs/2012030200/gfsnh-1-6.png?0?0. With all of that cold up in the arctic, there is clearly a risk of a wintry outbreakat any time. This is the same every year. Personally im not looking for anything after recieving even more snow this year than last year. But i can understand why some in the west are, as the winter has been a very poor one there. And I certainly wont be looking for any warm weather, not until april at least anyway

[stewfox]

shame hardly no one is up to see this chart, probably the best chart i have seen for march - 16 uppers in mid march

just a fantasy though and won't happen

http://modeles.meteo...11-0-276.png?18

-16c uppers in mid March for Moscow I assume is not that uncommom, that is what that chart is showing

.

[karyo]

Perhaps this is why people are "looking for cold". http://modeles.meteo...nh-1-6.png?0?0. With all of that cold up in the arctic, there is clearly a risk of a wintry outbreakat any time. This is the same every year. Personally im not looking for anything after recieving even more snow this year than last year. But i can understand why some in the west are, as the winter has been a very poor one there. And I certainly wont be looking for any warm weather, not until april at least anyway

I know you are focusing on the Arctic but this chart for me is a reminder of how amazing this winter has been for Turkey. The cold started in October and pretty much stayed uninderupted! Snow depths increased as there was hardly any melt and many areas are still burried under the snow. Even today, Turkey has -8c uppers while areas further west and east are warmer. Turkey was this winter's sweet spot and jackpot lottery winner!

Out of topic of course and I apologise but there is not much to discuss about our weather prospects lol

Karyo

[Lewis]

Nothing overly cold on the horizon and nothing really to get a coldie fan excited.

A brief spell of cooler weather, with the chance of some snow showers for Scottish Highlands, with a few settled days for the rest of England & Wales. Sunny crisp days for some, with the chance of some showers followed by frost at night before the Atlantic makes a reappearance bringing with it a bought of wet and windy weather, possibly very windy for some parts, particularly western and SW parts.

Atlantic looks like it really does gear up, and I would be surprised to see a change to a more settled pattern bringing high pressure anytime soon.

I cannot see much change in the models between T0-T120 just minor adjustments on the track and intensity of the Atlantic depressions.

Never say never, but I doubt we'll see any snow until next winter now, i'm pretty confident for my neck of the woods anyhow. You never know though, we did end up with a snowy Easter a few years ago.

Lewis

Edited March 2, 2012 by ~SFL~

[Zakos]

I know you are focusing on the Arctic but this chart for me is a reminder of how amazing this winter has been for Turkey. The cold started in October and pretty much stayed uninderupted! Snow depths increased as there was hardly any melt and many areas are still burried under the snow. Even today, Turkey has -8c uppers while areas further west and east are warmer. Turkey was this winter's sweet spot and jackpot lottery winner!

Out of topic of course and I apologise but there is not much to discuss about our weather prospects lol

Karyo

It certainly has , amazing weather for them this winter. Accuweather i think did predict for them to have a cold winter and us to be slightly milder so they were right. My relatives in cyprus have seen snow, nothing unusual at all in the mountains but at around sea level they had snow in the outskirts of Nicosia, a very very rare occurrence. I can recall many nights were Ayia napa had colder nights than most of the UK, And Ayia napa is right on the mediterranean cost! Nothing really unusual in the UK's weather this winter, apart the worrying lack of rainfall. Well as the old saying goes if march comes in like a lamb, it goes out like a lion. No real sign of this of models just yet but i wouldn't be surprised to a see a cold end to march

[karyo]

Nothing overly cold on the horizon and nothing really to get a coldie fan excited.

A brief spell of cooler weather, with the chance of some snow showers for Scottish Highlands, with a few settled days for the rest of England & Wales. Sunny crisp days for some, with the chance of some showers followed by frost at night before the Atlantic makes a reappearance bringing with it a bought of wet and windy weather, possibly very windy for some parts, particularly western and SW parts.

Atlantic looks like it really does gear up, and I would be surprised to see a change to a more settled pattern bringing high pressure anytime soon.

I cannot see much change in the models between T0-T120 just minor adjustments on the track and intensity of the Atlantic depressions.

Never say never, but I doubt we'll see any snow until next winter now, i'm pretty confident for my neck of the woods anyhow. You never know though, we did end up with a snowy Easter a few years ago.

Lewis

Stratospheric temperatures are nose diving again to much below average so I'd expect the jet to remain strong this spring. Boring for us but good for the Arctic ice I guess.

Karyo

[Tim Bland]

Look at the strength of the PV over greenland. Will be tad windy up there! Still no signs of the PV weakening or fragmenting. It has been a right pain in the back side this winter!

[Timmytour]

Look at the strength of the PV over greenland. Will be tad windy up there! Still no signs of the PV weakening or fragmenting. It has been a right pain in the back side this winter!

You beat me to it about the wind in Greenland....slight wind chill!

I sense the AH has been wanting to link up with a Scandi high.....but keeps getting knocked back down. Beginning to think next week is going to start a little chilly but end up like summer!

[Reefseeker]

It certainly has , amazing weather for them this winter. Accuweather i think did predict for them to have a cold winter and us to be slightly milder so they were right. My relatives in cyprus have seen snow, nothing unusual at all in the mountains but at around sea level they had snow in the outskirts of Nicosia, a very very rare occurrence. I can recall many nights were Ayia napa had colder nights than most of the UK, And Ayia napa is right on the mediterranean cost! Nothing really unusual in the UK's weather this winter, apart the worrying lack of rainfall. Well as the old saying goes if march comes in like a lamb, it goes out like a lion. No real sign of this of models just yet but i wouldn't be surprised to a see a cold end to march

My husband took photos of our house half way between Limassol and Troodos in Cyprus covered in snow on Tuesday. Never seen that before. The Troodos mountain roads are all closed, and even lower down towards the coast than Platres was closed yesterday with many villages cut off. Due to warm up today again.

Edited March 2, 2012 by Reefseeker

[karyo]

It certainly has , amazing weather for them this winter. Accuweather i think did predict for them to have a cold winter and us to be slightly milder so they were right. My relatives in cyprus have seen snow, nothing unusual at all in the mountains but at around sea level they had snow in the outskirts of Nicosia, a very very rare occurrence. I can recall many nights were Ayia napa had colder nights than most of the UK, And Ayia napa is right on the mediterranean cost! Nothing really unusual in the UK's weather this winter, apart the worrying lack of rainfall. Well as the old saying goes if march comes in like a lamb, it goes out like a lion. No real sign of this of models just yet but i wouldn't be surprised to a see a cold end to march

Yes, my hometown in northern Greece has also seen a very cold second half this winter!

I doubt any northern blocking will develop this March due to the cold stratosphere. Cold zonality may be a possibility though if the jet decides to travel south (the quiet sun may encourage this) and the Azores high moves to the west a bit.

Alternatively, we can have the horrific (for me) scenario of high pressure over the continent and low in the Atlantic with southwesterlies...

Karyo

Edited March 2, 2012 by karyo

[Frosty.]

The Gfs 06z has sundays low much further north and covering a far wider area with the chilly, wet and windy weather. This also has an impact further north with much less chance of wintry showers as a ridge quicky pushes into scotland but the result of the low being further north is to slow down the changes next week with the south having light winds and relatively high pressure after monday's residual bad weather clears away slowly southeast and northern britain having a slower breakdown to milder, wet and windy weather. There is some colder air into the far north at times but the main theme in FI is for anticyclonic weather to become dominant with plenty of sunshine but also some overnight frosts, by the end of FI the charts look more springlike with a southerly flow.

Edited March 2, 2012 by Frosty039

[snowmadchrisuk]

I agree not much on the Cold front , The depth of that Low on Sunday should create a little interest .. Strong Winds for France for Sure . The Met Office are now hinting at an above average nation wide Warm spell towards the end of the Month .. I am sure this would be welcomed by most as if anybody remembers last April , we can be heading into Mid 20's by then ,.

[Thundery wintry showers]

The current set of model outputs remind me a lot of a pattern that was frequent in many recent Marches (1997-2000, 2002, 2007, 2009-2011), high pressure stubbornly around southern areas promoting a west to south-westerly regime across the UK giving consistent but unexceptional warmth. Sunshine amounts are generally above average in central southern and eastern England and below in western Scotland and Cumrbia, though mid-March 1998 had a cloudy high everywhere. The implication is also well below average rainfall, except for the channel low this weekend which may bring snow on high ground but rain at low levels.

The ECMWF ensembles paint a colder and more unsettled picture after T+168 than the operational with some cold zonality establishing, but next week's cold zonality has disappeared from all model outputs with high pressure too close by to the south.

For those after good "outdoor activities" weather the southerly tracking low for the weekend is somewhat frustratingly timed, but the suggested washout on Saturday may help alleviate the drought problems in the south and east.