Model Discussion And Chat 19th Feb.2012

[Summer Sun]

Its easy to sum up ECM tonight, high pressure dominates.

[nick sussex]

Not much ensemble support for the ECM operational run in terms of it placing the high that far north at 168hrs:

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!168!pop!od!enfo!enplot!2009112700!!/

[legritter]

ok ,looking at all charts this week looking very mild ,.next week wc /27th dry /mildish ,to start . but im looking at there being a pay back in march ,or should i say a possible cold spell , GFS is hinting at high pressure in its later stages ,and reading between the lines with met of further outlook ,its seems to be covering itself with a cold spell mentioned .perhaps with azores high sinking or scramming of ,this is just a hunch ,but im sure that the recent cold spell was not the only mayor cold shot of the winter , although if it does arrive in march it will be classed by most as early spring .early march cold weather can be very interesting . especially with stronger sun and good mixing ,perhaps .perhaps this weeks high temperatures could be the last dying gasp of our friend MR AZORES cheers legritter

[William Houston]

yeh would be nice to get some snow capped peak pics in march ,fingers crossed

[bluearmy]

Ecm spreads are interesting in fi. If this isn't a rogue ens suite then I suspect the output will begin to become 'watchable' from a cold perspective over the next few days.

[Frosty.]

The Gfs and Ecm 12z show anticyclonic weather in the next few weeks with the unsettled, milder and windy weather becoming restricted to the far north of the uk, the ecm is even more high pressure dominated than the gfs with fine weather for all of the uk eventually and although the week ahead looks very mild or even warm, the further outlook under high pressure would at least have some frost and fog overnight meaning the day's would not be as mild but no sign of snow anywhere for the next few weeks at least. This winter has been mainly abysmal for snow and frost and the way it's ending is rather fitting in my view.

[Geordiesnow]

Looks like I may of underestimated the clouds amounts for Thursday, it will be interesting how much sunshine there will be by the end of the week as of course this will affect the temperature and could give us a proper taste of spring. I suspect Thursday may start cloudy but the sun will break through for eastern areas in particular but how much sunshine there will be won't be decided until the day itself I feel but it will probably feel very mild regardless.

GFS still really want to blow up the PV like mad in FI and there is support from the ECM for this, not good for cold weather for our shores but its something to keep an eye on thats for sure, could be a very cold End to February for parts of the states/Canada.

[legritter]

as GEORDIE SNOW said ,could be a very cold end feb for states /canada , LETS HOPE IT RUNS IN OUR DIRECTION ,must keep an eye on jet streem , i know there,s a saying of 10 days later for us , but doesnt happen that way very often , but CAN ,and has and will again , plenty of deep cold in arctic ,only looking at end of GFS run ,perhaps ECM will start giving us some candy soon , certainly interesting days to come , as i said ,perhaps MR AZORES is giving his best this week before scramming off , cheers gang

[nick sussex]

Ecm spreads are interesting in fi. If this isn't a rogue ens suite then I suspect the output will begin to become 'watchable' from a cold perspective over the next few days.

Looking at the extended ECM ensembles they're not really that supportive of a big change:

http://www.weerplaza.nl/15daagseverwachting/default.asp?type=eps_pluim

Although high pressure may get further north with time I suspect the cold air is going to end up in southern and se Europe, the spreads do show some support though for lower pressure in the northern Med.

Edited February 19, 2012 by nick sussex

[Nick F]

Pressure anomaly chart for winter so far is pretty much what you said.

That azores high has to crack sooner or later!

Thanks for producing that chart and confirms my thoughts for the dominating heights pattern this winter.

Makes me wonder what is causing the persistence of the Azores ridge to displace towards western Europe, could be SST driven as others have said? The dominance of the ridge is certainly a worry longer term wrt to lack of rainfall for parts of England, lets hope it does crack sooner than later!

[Uncle_Barty]

Thanks for producing that chart and confirms my thoughts for the dominating heights pattern this winter.

Makes me wonder what is causing the persistence of the Azores ridge to displace towards western Europe, could be SST driven as others have said? The dominance of the ridge is certainly a worry longer term wrt to lack of rainfall for parts of England, lets hope it does crack sooner than later!

I'm sure it will by late May and we'll be back to a Greeny high again just when we don't want it, just in time to wreck another summer!

[Milhouse]

Not much ensemble support for the ECM operational run in terms of it placing the high that far north at 168hrs:

http://www.ecmwf.int...t!2009112700!!/

Its further out towards 240h where the ECM ensemble mean shows growing support for the Azores to throw a decent ridge northwards. Although looking at the upper temperatures they are above 0C for the majority of the country so i believe that if we do get HP over the UK it will initially bring average/slightly above daytime maxima, which in light winds should feel rather pleasant. Thereafter, should HP get far enough north to bring in a colder easterly feed then we would see temperatures falling.

Edited February 19, 2012 by Milhouse

[snowmadchrisuk]

Interesting 18z , Makes Thursday even Warmer 16c Widely and then tries an undercut and tries to bring down something Colder as we head towards +180 . Very different pattern to the 12z .

[nick sussex]

My interest level is now raised to a 4/10!

I think its becoming apparent that we need to see that low exiting the ne USA as developed as possible. The GFS 18hrs run scrapes more interest than we've seen for days but will it still be there tomorrow?

[snowmadchrisuk]

Oh my god it is decided to go Epic in FI , this run might get a few people out of hiding but I guess we will be lucky if it is there in the morning .

[coldwinter]

Pub run special, you could see it was going to be a better evolution as soon as that ne usa trough was more amplified. But its the 18z.

Ryan.

[Thundery wintry showers]

It is worth checking out the heights and the surface and 850hPa temperatures- the synoptics might look impressive for cold/snow but there isn't much of a cold pool to tap into when the north-easterly arrives. Prior to T+240 the resulting weather would probably be mostly cloudy with a little sunshine and a few wintry (sleet/graupel mainly) showers for eastern areas, though after T+240 things do get rather colder and snowier. However it does illustrate that a seemingly "locked in" warm zonal pattern can be overthrown suddenly without much warning.

[karyo]

It is worth checking out the heights and the surface and 850hPa temperatures- the synoptics might look impressive for cold/snow but there isn't much of a cold pool to tap into when the north-easterly arrives. Prior to T+240 the resulting weather would probably be mostly cloudy with a little sunshine and a few wintry (sleet/graupel mainly) showers for eastern areas, though after T+240 things do get rather colder and snowier. However it does illustrate that a seemingly "locked in" warm zonal pattern can be overthrown suddenly without much warning.

Never mind, I'll take it!

Karyo

[Cloud 10]

My interest level is now raised to a 4/10!

Try the CFS for March to increase that interest level!

Purely for entertainment value of course.....ahem :lol:

[nick sussex]

Bless the GFS 18hrs run for at least trying!

After days of the most dismal output imaginable from a cold perspective it's decided to throw out one of its specials. You could say it at least has support for the more amplified eastern USA trough from the ECM but really the chances of this run verifying are minimal.

At least it gives us something to talk about until the inevitable let down in the morning!

Edited February 19, 2012 by nick sussex

[snowmadchrisuk]

It is worth checking out the heights and the surface and 850hPa temperatures- the synoptics might look impressive for cold/snow but there isn't much of a cold pool to tap into when the north-easterly arrives. Prior to T+240 the resulting weather would probably be mostly cloudy with a little sunshine and a few wintry (sleet/graupel mainly) showers for eastern areas, though after T+240 things do get rather colder and snowier. However it does illustrate that a seemingly "locked in" warm zonal pattern can be overthrown suddenly without much warning.

If it ended up how the 18z shows though it would be an extended Cold spell and Snow would come The -10's soon creep in as the pattern develops . Praying that that this is a new trend, I of course have big doubts though ,

[Gowon]

Try the CFS for March to increase that interest level!

http://modeles.meteo...nh-0-360.png?06

Purely for entertainment value of course.....ahem :lol:

Yeah and the GFS 18z looks very similar to that run.

[cooling climate]

This mornings UKMO t144 chart was the first to show a glimmer of better times ahead for

cold enthusiasts only to drop it this afternoon. The ECM then picked it up at t144-168 and

now the 18z GFS run except the 18z has amplified the pattern a lot further.

Certainly something to watch.

[Nick F]

Be interesting to see where the 18z operational sits amongst the ENS members, one would think a cold outlier, though ECM does also slow and dig deep the trough coming out of eastern N America and across the N Atlantic in the later stage of the run.

[snowmadchrisuk]

Yeah and the GFS 18z looks very similar to that run.

Yes what the trend seems to be lately from runs such as the CFS and even the ECM to an extent is to build Low Pressure to our SW this has the effect if placed right of propping up our resident High and causing runs like the 18z .