Model output discussion - 20th Feb onwards

[knocker]

Similar story from the GFS this morning. Cold and dry until a rain band sweeps in next Tuesday with the same two caveats, The rain/snow in the SW Friday and Sat is still to be resolved and frequent wintry showers (probably snow) in the NE/E over the weekend.

[chris55]

GFS trying to disrupt the incoming low into next week with that chunk of Scandinavia high developing a little more robustly. Looks quite similar to the pattern a few weeks back.

we all know how the models tend to over develop the westward push from the Atlantic in the mid term so one to watch.

ECM much more mobile.

 

 

[Gowon]

6 minutes ago, chris55 said:

GFS trying to disrupt the incoming low into next week with that chunk of Scandinavia high developing a little more robustly. Looks quite similar to the pattern a few weeks back.

we all know how the models tend to over develop the westward push from the Atlantic in the mid term so one to watch.

ECM much more mobile.

 

 

 Yep, and the GEM goes the same way with pressure rising to our NE which forces the lows SE into Europe. 

 

 

[Man With Beard]

It's increasingly looking like this weekend may be the final chance of seeing flakes of some sort for many, as it just isn't working out with regards northern blocking thereafter.

The ECM is particularly poor in that respect as it not only flattens out the pattern between D6-D10, but it removes deep cold from our NE too so any temporary NEly further down the line would be chilly and nothing else.

In fact, the spring brigade may find the run very welcoming, as I can foresee temperatures reaching the teens with sunny spells on the east coast.

The GFS attempts to build a stronger high to our West, but still not in the category of "northern blocking", so any temporary northerly is unlikely to be cold enough for snow away from the north.

Still, something may develop for Sunday I feel, with a good easterly in reasonably cold uppers.

[knocker]

Probably the most significant observation of this morning's ecm run is the virtual lack of any precipitation of any kind in the ten days. The colder regime gives way to a more Atlantic influenced one and thus nearer average temps post Tuesday.

[MR EXTREMES]

Looking pretty dry  chilly to start then signs of milder air in the ecm very welcome.

be glad to see the back of this winter.

pv certainly been a major factor in the past few years.

if there's strong pv next winter I'd call for another repeat of the last few.

good sign seeing the glosea model and ec long range doing good job of long range forecasting,

so rubbish winter but it means that in such a messy winter with many background signals like the strong El Niño these models preformed exceptional so be worth putting faith in them for future ideas for long range.

anyway enjoy the sunshine and crisp conditions and knockers daffs he's back from his winter hibernation hopefully he can start to show some spring warmth and sunshine.

 

[Gibby]

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON WEDNESDAY FEB 24TH 2016

THE CURRENT GENERAL SITUATION   The slack North or NW flow established over the UK will back more Westerly tomorrow as Low pressure begins to transfer South to the West of the UK tomorrow pushing a trough slowly East towards the SW approaches.

http://www.wetterzentrale.de/pics/Rtavn001.gif

 CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the UK lies between 2000ft to 2500ft across the UK with the lowest figures towards Northern Scotland where some snow showers are occurring with wintry showers on hills of the Lake District and Cumbria as well at times.

http://www.snow-forecast.com/maps/dynamic/uk

http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif

MODELS-2 WEEK HEADLINE  Some rain or showers at times with snow over hills. Temperatures mostly near or somewhat below average.

THE GFS JET STREAM FORECAST  The Jet Stream is moving South to the West of the UK over the next few days and then turns East across Spain and the Mediteranean Sea. Thereafter the flow although ebbing and flowing maintains a direction of flow from the NW to the SE next week and probably beyond close to or across the UK. 

http://www.netweather.tv/index.cgi?action=jetstream

GFS OPERATIONAL The GFS Operational Run today shows Low pressure developing and sliding SE to the SW of the UK and down over Biscay and Spain with a developing and cold east flow developing over the weekend in the South. A little rain or sleet on the SW for a time will give way to a largely dry weekend with sunshine in the North and a few wintry showers near Eastern coasts. Next week sees winds backing Westerly for a time and introducing more changeable conditions alternating between cloudy and damp conditions with cold and showery Northerly flows with some snow at times on hills and in the North and East. With High pressure increasingly lying to the West of the UK later in the period there looks no quick exit to the rather cold North or NW feed of air as we move into March. 

GFS CONTROL RUN The Control Run today is different in the second week as it keeps High pressure further towards the South and SW of Britain rather than to the West meaning there will be more lengthy spells of less cold Westerly winds in the changeable theme of the second week.

http://www.wetterzentrale.de/pics/Rtavn1441.gif

http://www.wetterzentrale.de/pics/Rtavn3841.gif

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0

http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0

GFS ENSEMBLE DAY 14 DATA  The GFS Clusters today show a mix of options with the 50% share going for High pressure lying close to the SW or South in two weeks time with dry and bright conditions in a Westerly breeze in average temperatures. Some Northerly charts are also shown by some members amounting to 40% so no clear guarantees of which option is likely to verify.

http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD=

UKMO The UKMO model this morning shows an Easterly flow developing across the South towards and over the weekend as Low pressure having moved down to Spain moves ENE through the Med. A ridge follows South across the UK cutting off the cold and rather cloudy flow with a day or so of frosty weather before a flat Westerly pattern looks like developing next week with less cold weather with rain at times especially in the North towards midweek.

http://www.wetterzentrale.de/pics/Rukm1441.gif

THE FAX CHARTS The Fax Charts today illustrate the story of the raw data well with low pressure moving past the SW with some rain or sleet and hill snow from an occlusion over Friday and early Saturday before it is swept away to the SE to leave a cold and raw NE flow with a lot of cloud and a few wintry showers near the SE for a time before the ridge over Scotland slips SE to other areas by the start of next week.

http://www.weathercharts.org/ukmomslp.htm#t120

GEM GEM today shows good agreement with other outputs showing the passage of Low pressure to the South of the UK with a raw East wind at the weekend followed by a cold ridge of High pressure and the subsequent changeable and rather cold conditions following from the NW with rain and showers turning wintry at times especially in the North and East through the latter stages of next week.

http://www.wetterzentrale.de/pics/Rgem2401.gif

NAVGEM NAVGEM too takes the same track of events over the next week with changeable synoptics amounting to maintaining rather cold weather and although a lot of dry weather some wintry showers near coasts at times, a little rain or sleet in the SW on Friday and more generally next week as a chilly NW feed of air establishes.

http://www.wetterzentrale.de/pics/Rnvg1681.gif

ECM ECM this morning looks much like UKMO this morning at the Day 6 stage and this agreement supports less chance of any further cold air reaching the South after this weekends East winds and subsequent ridge passes. As High pressure is more pronounced South of the UK next week supporting a flatter Westerly flow from the Atlantic rain at times is likely in temperatures returning to average levels with any colder showery interludes restricted to the far north and NE

http://www.wetterzentrale.de/pics/Recm2401.gif

ECM 10 DAY MEAN The 10 day mean chart has backed the flow more Westerly across the UK this morning than over recent outputs suggesting that more members are moving away from a cold North or NW feed towards a flatter Westerly pattern with a more even split of members culminating in a chart that can offer periods of both weather types rather cold or average.

http://www.wetterzentrale.de/pics/Reem2401.gif

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The theme remains for a rather cold couple of weeks though ECM and UKMO support a milder Westerly pattern later.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.5 pts and GFS at 99.4 pts.  At 3 days ECM is leading with 97.6 pts to UKMO's 97.1 pts while GFS lags behind at 96.4 pts. At 5 days ECM leads with 91.6 pts to UKMO at 89.7 pts and GFS at 87.9 pts. Then at 8 Days ECM has the leading spot from GFS with 70.7 pts to 64.7 pts. Finally at Day 10 ECM leads today at 53.9 pts to GFS's 51.4 pts.

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png

MY THOUGHTS  The models still support a lot of rather cold synoptics over the next few weeks but there are cracks in the pattern within the models with a marked change in the Euro's longer term this morning which seem to support more chance of a flatter and less cold Westerly pattern establishing later next week recovering temperatures to closer to average levels for many away from the far North. The GFS Clusters too support the above change with High pressure showing much more consistency in positioning itself just to the South of the UK rather than ridging North through the Atlantic. Though not conclusive this is a big shift away from the potentially cold and in places wintry start to March all models seem to be leaning towards as recently as yesterday and while the previous model predictions still hold some support it is without doubt a new trend that has gained quite a bit of support within a short period of time so should be taken seriously. However, in the meantime we have a rather cold and messy picture over the next 3-4 days as Low pressure slips SE to the SW of the UK and threatens some patchy rain, sleet or snow into the SW for a time and then as a NE flow develops for a time the SE and East coasts could see some wintry showers for a time later in the weekend. Then a few days of cold and crisp weather with night frosts lead us into the pattern highlighted at the top of my report with the weather taking one of two ways. As said earlier there is still some support for a lot of cold NW or North winds at times with sleet or snow showers at times especially over the North and East with short wet spells in between as new Low pressure passes Se to the NE of the UK. Alternatively the UKMO, GFS Clusters and ECM route would support cloudier and less cold weather with rain at times in a Westerly flow with the North and West as usual in these situations capturing the most wind and rain. In expressing my own opinion and given the theme of the Winter past I would come down on the side that the Euro's may well have the right message this morning with a gradual return to average temperatures later next week with some rain at times especially in the North being the growing outcome likely with only short colder interludes towards the North and NE.           

Next Update Thursday February 25th 2016 from 09:00 

[Purga]

Before everybody gets too depressed the GEFS are still showing a majority of members (including the Op & Control) going for an extended colder than average period after a brief warm up next week.

Of course these can and do often 'flip' but at least the sign is there at the moment.

 

Edited February 24, 2016 by Purga

[Summer Sun]

Quick look at the GFS London ens shows it remaining fairly dry for the rest of the month then into early March it turns more mixed

[Frank Trough]

10 minutes ago, Purga said:

Before everybody gets too depressed the GEFS are still showing a majority of members (including the Op & Control) going for an extended colder than average period after a brief warm up next week.

Of course these can and do often 'flip' but at least the sign is there at the moment.

 

I don't know if just "colder than average" in march is going to set too many pulses racing if it doesn't deliver chances of snow. Of course up north it probably would give some chances in favoured locations so some interest there.

But if it's simply colder than average weather without snow you're after then you might as well look forward to May to August because you can bet we will get our fill of below average days/months in that period.

 

Surely these maxima for sunday in the southeast are a bit overcooked aren't they? It will still be February in a brisk north easterly?

[Summer Sun]

1 minute ago, Certain kind of fool said:

I don't know if just "colder than average" in march is going to set too many pulses racing if it doesn't deliver chances of snow. Of course up north it probably would give some chances in favoured locations so some interest there.

But if it's simply colder than average weather without snow you're after then you might as well look forward to May to August because you can bet we will get our fill of below average days/months in that period.

 

Surely these maxima for sunday in the southeast are a bit overcooked aren't they? It will still be February in a brisk north easterly?

If the maxes do get around 7c it certainly wont feel anything like that with a strong wind as the wind chill chart shows

[Cloud 10]

00z ECM op. run looks very different to the ensemble mean,and is likely an outlier with those Euro heights.

 

op run..ens.mean

[stainesbloke]

1 hour ago, Certain kind of fool said:

I don't know if just "colder than average" in march is going to set too many pulses racing if it doesn't deliver chances of snow. Of course up north it probably would give some chances in favoured locations so some interest there.

But if it's simply colder than average weather without snow you're after then you might as well look forward to May to August because you can bet we will get our fill of below average days/months in that period.

 

Surely these maxima for sunday in the southeast are a bit overcooked aren't they? It will still be February in a brisk north easterly?

Colder than average in March would be fine IF we could have weather like today/last night for an extended period (sunny and calm by day, frosty at night). I'd quite happily take that over any nasty slush. If we get a blizzard here in the South with ice days fine, but that's very unlikely so I'd rather it stayed mainly dry and the chill will slow down plants breaking dormancy too early after the extremely mild 'winter' we've just endured.

Edited February 24, 2016 by stainesbloke

[snowangel32]

Simple word to explain the models cold but bone dry unless you live in Scotland or the far east coast might get a shower but even that looks unlikely. A true wishbone effect going on. All that talk of get the cold in and the snow will follow is just a myth. As the current setup demonstrates although with the clear skies some very harsh and hopefully air frosts are on offer so not all bad. It's like mission impossible for low level snow this winter. The PV has been utterly dominate and set up two base camps in Greenland and the US East coast. Let's hope for better next winter. 

[winterof79]

Ecm not on the money for me yet.

GFS 06z trying to finish off the Canadian lobe.There is also a front moving in early next week in to cold air.One of the scenarios the MET allude to.

 

I may add that any weakening would allow heights you know where.....

Edited February 24, 2016 by winterof79

[feb1991blizzard]

Could be a stunning GFS FI coming up, already decent snow by Just over the 200 mark.

[weirpig]

If only a month or so earlier this place would be in melt down   stiff easterly breeze and -12 heading across europe    what a awful winter  grrr

[Banbury]

19 minutes ago, weirpig said:

If only a month or so earlier this place would be in melt down   stiff easterly breeze and -12 heading across europe    what a awful winter  grrr

Just shows we can get the right set up ,its all about timing

[Ravelin]

No quick return to a westerly Atlantic regime if the GFS 6z FI is to be believed. Pretty much blocked off from t192 through to t384...

In reality, since there' little coming from a westerly or south westerly direction even prior to t192 you could say it's blocked from t0 to the end of the run.

Especially liek the little feature running over the top in the latter stages and down the North Sea...

[nick sussex]

Chalk and cheese this morning. The ECM brings back the Euro high, removes the west USA amplified ridge and flattens the upstream pattern. The GFS keeps those in place and develops a wintry spell for the UK.

At this time I'd be dubious of the ECM operational run, there is expected to be a brief flattening of the ridge over the western USA but this is expected to re-amplify, instead the ECM takes shortwaves through flattens this and doesn't re-amplify the pattern in the west USA.

THE RE-AMPLIFICATION OF THE WESTERN RIDGE IN BETWEEN AND AFTER SHORTWAVES CONTINUES WITH EVEN HIGHER HEIGHTS IN THE RIDGE AXIS INTO THE MIDDLE OF NEXT WEEK...HIGHLIGHTED BY THE GFS FORECASTS OF 500 MB HEIGHT ANOMALIES OF 1-2 STD DEVIATIONS ABOVE NORMAL. THIS LEADS TO MAINTAINING THE ANOMALOUSLY WARM CONDITIONS ACROSS THE WEST

The above is what NCEP expect to happen so its a surprise to see its morning output. If the ECM however has found a new correct trend then I think that's game over for any wintry weather.

[karyo]

8 minutes ago, nick sussex said:

Chalk and cheese this morning. The ECM brings back the Euro high, removes the west USA amplified ridge and flattens the upstream pattern. The GFS keeps those in place and develops a wintry spell for the UK.

At this time I'd be dubious of the ECM operational run, there is expected to be a brief flattening of the ridge over the western USA but this is expected to re-amplify, instead the ECM takes shortwaves through flattens this and doesn't re-amplify the pattern in the west USA.

THE RE-AMPLIFICATION OF THE WESTERN RIDGE IN BETWEEN AND AFTER SHORTWAVES CONTINUES WITH EVEN HIGHER HEIGHTS IN THE RIDGE AXIS INTO THE MIDDLE OF NEXT WEEK...HIGHLIGHTED BY THE GFS FORECASTS OF 500 MB HEIGHT ANOMALIES OF 1-2 STD DEVIATIONS ABOVE NORMAL. THIS LEADS TO MAINTAINING THE ANOMALOUSLY WARM CONDITIONS ACROSS THE WEST

The above is what NCEP expect to happen so its a surprise to see its morning output. If the ECM however has found a new correct trend then I think that's game over for any wintry weather.

Yes, I'd be surprised if the ECM has the correct idea. Based on the way the stratosphere looks at the moment and the forecast for the next two weeks, I would expect repeated attacks from the northwest/north. Certainly no euro high.

 

Karyo

[Man With Beard]

Hmmm ... as others have alluded, the ECM mean still gives a chance of something colder developing ala GFS - main trough to our NE, perhaps stronger heights to our west that the op suggests - can't write off a further shot of cold at the end of next week yet. But it's decidedly dodgy.

Looking at the latest GEFS, the consensus is certainly to keep on the colder side - and quite confident of a flake or two in the capital before the weekend is out:

http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=306&y=141&ville=Londres

Yes, same on extended ECM ensembles - op is an outlier, most runs bring back the chilly weather (rather than "cold") by D9 and keep it that way till the end:

 

 

[nick sussex]

1 minute ago, karyo said:

Yes, I'd be surprised if the ECM has the correct idea. Based on the way the stratosphere looks at the moment and the forecast for the next two weeks, I would expect repeated attacks from the northwest/north. Certainly no euro high.

 

Karyo

Yes the odds favour that scenario so the ECM was a big surprise this morning, its as flat as a pancake upstream later in its operational run. Even the UKMO disagrees with it at T144hrs over the western USA. That takes shortwaves through and re-amplifies that ridge.

[Yarmy]

20 minutes ago, nick sussex said:

Chalk and cheese this morning. The ECM brings back the Euro high, removes the west USA amplified ridge and flattens the upstream pattern. The GFS keeps those in place and develops a wintry spell for the UK.

At this time I'd be dubious of the ECM operational run, there is expected to be a brief flattening of the ridge over the western USA but this is expected to re-amplify, instead the ECM takes shortwaves through flattens this and doesn't re-amplify the pattern in the west USA.

THE RE-AMPLIFICATION OF THE WESTERN RIDGE IN BETWEEN AND AFTER SHORTWAVES CONTINUES WITH EVEN HIGHER HEIGHTS IN THE RIDGE AXIS INTO THE MIDDLE OF NEXT WEEK...HIGHLIGHTED BY THE GFS FORECASTS OF 500 MB HEIGHT ANOMALIES OF 1-2 STD DEVIATIONS ABOVE NORMAL. THIS LEADS TO MAINTAINING THE ANOMALOUSLY WARM CONDITIONS ACROSS THE WEST

The above is what NCEP expect to happen so its a surprise to see its morning output. If the ECM however has found a new correct trend then I think that's game over for any wintry weather.

Yes, backed up their 8-14 day anomaly chart from yesterday:

 

We'll see though as the UKMO looked pretty underwhelming at T144 too.

Edited February 24, 2016 by Yarmy

[knocker]

The ecm 10-15 anomaly from last night and this morning is not a million miles from NOAA. There has been no significant pattern change upstream. The 10-15 is quite similar to the T240 chart but with a more sharply defined Atlantic ridge/trough thus a touch more meridional.

Edited February 24, 2016 by knocker