Model output discussion pm 13/01/2016

[wishingforsnow]

10 minutes ago, booferking said:

A few of these are starting to appear in the GEFS.

Drool worthy charts there for coldies 

[swilliam]

Some very tasty FI ensembles tonight (where is Mucka when you need him)

 

 

Nothing better than this though (just for fun but shows what is possible)#

 

 

No prizes which one is P16.

 

However overall everything is lower - something interesting is going to happen

 

[Derbyshire Snow]

22 minutes ago, nick sussex said:

With where the vortex is positioned its very unlikely we'll see a proper Greenland high initially, many colder spells have started with a Scandi high and retrogression with then a trough dropping south into Scandi and then pressure rising over Greenland.

The historically good spells had that type of high pressure  musical chairs for a lengthy period. I'm not for a moment suggesting that's round the corner! lol

We first need the Euro high to ridge north in response to troughing digging far south into the Atlantic and then hope for a change of luck which is long overdue, regardless of this more seasonal spell it hasn't delivered more nationwide and has just papered over the cracks.

Crunchy snow and sub zero maxima is whats needed to salvage this winter.

Hi Nick,

What i am finding a problem with is i cant see in the near future how a scandi high will develop unless something extends from Siberia. The high over Europe will struggle to reposition itself over Scandinavia unless we can get these depressions to be cut off, heights needed to develop from Greenland to push them south or cut them off so that one tracks west Greenland instead. I do agree though, synoptics not easy for that as well.

We have such a poor area to get the ideal synoptics , but makes model; watching not boring

[Timmytour]

Maybe this might go on to resemble the winter of 1954/55.  November and December were mild months, January had its cold spells with snowy moments but then got milder towards the end....and February was epic!

It went from this to this  23rd Jan 1955 to 12th Feb 1955






 

[Derbyshire Snow]

thats what i have been trying to explain this evening. that is the perfect chart. High pressure over Greenland > Low pressure in to central Europe and atlantic jet cut off.

That must have been severe cold

Edited January 18, 2016 by Derbyshire Snow

[Timmytour]

12 hours ago, Timmytour said:

Lets put this mornings 6z run alongside these for comparison.......so that now we are into T60....

 

To me, even in the very short range, there's still enough differences to indicate nothing is set in stone just as yet with a bigger inclination (though far from an overwhelming one) that energy  will be sent south east.  I agree the chances are small, but it's not out of the question that the models will flip in thier approach to the end of next week, just as they have done for for that time-frame for pretty much  the last two weeks!!

and tonight's 18z at T48 is



Even at such a short time-frame, for me there's some difficulty getting a handle on the amount of energy below Greenland  and the direction it heads in which is giving different returns further down the line with each run
 

[ScottSnow]

Not a bad little cold spell here. Lying snow since Thursday now. 

Think we will see heights rise to our north east again by months end and we will see the cold return from the east as the ECMWF run hints at in the later stages.

Also don't think the temps will warm up later this week to what we were experiencing in Dec. Probably return to average temps then possible gradual cool down from the east heading into Feb. 

Interesting model watching ahead.

[Derbyshire Snow]

4 minutes ago, Timmytour said:

and tonight's 18z at T48 is



Even at such a short time-frame, for me there's some difficulty getting a handle on the amount of energy below Greenland  and the direction it heads in which is giving different returns further down the line with each run
 

 

4 minutes ago, Timmytour said:

and tonight's 18z at T48 is



Even at such a short time-frame, for me there's some difficulty getting a handle on the amount of energy below Greenland  and the direction it heads in which is giving different returns further down the line with each run
 

if that high pressure would weaken in Europe and allow the energy( lows) in the atlantic to push south

[Derbyshire Snow]

interesting theories tonight . It should be a muddling week of synoptics and then lets hope we get some positive cold agreement in about a  weeks time.

The interest in this cold spell has now waned , just a few nice frosts.

 

[bryan629]

i proper take my hat off to this guy... cant wait for his blog tomorrow night

Judah Cohen ‏@judah47  5 hrs5 hours ago

If I am sacrificing my holiday to spend the entire day on the AO blog, you know I think it is going to be good

 

 

[summer blizzard]

GFS0z very close at day 9.

[Northernlights]

5 hours ago, Timmytour said:

Maybe this might go on to resemble the winter of 1954/55.  November and December were mild months, January had its cold spells with snowy moments but then got milder towards the end....and February was epic!

It went from this to this  23rd Jan 1955 to 12th Feb 1955




 I think this was the year in the fifties  farm cut off for 5 weeks only way out  walking through fields as roads remained  blocked.

 

 

[karlos1983]

im liking the setup being hinted at by the ECM this morning.

usual caveats, fi but still, following the 12z of yesterday, will the trend continue?

[That ECM]

I see the ECM is churning out some interesting output. 

[mountain shadow]

The game is most certainly afoot this morning. 

Models getting more confident of height rises to the North by the end of the month.

[karlos1983]

1 minute ago, mountain shadow said:

The game is most certainly afoot this morning. 

Models getting more confident of height rises to the North by the end of the month.

yes, not sure if I'd want to see the pattern evolve exactly like that, as you can see how that could be scuppered between 168 & 192. very small window for the high wedge to develop. But the trend is good 

[chris55]

While we are in the upcoming holding pattern, so to speak, as we wait for the next potential cold spell, the major positive I can see is the trend of high pressure being near by. Keeping things overall quite settled relitivly speaking.

cold settled week ahead, after today, then a gradual easing of the cooler air being replaced by a slightly milder feel, some wind and rain to come but overall dry!!

i don't think I could have handled a repeat of the Atlantic lows powering through like December.

 

Edited January 18, 2016 by chris55

[bluearmy]

6 minutes ago, mountain shadow said:

The game is most certainly afoot this morning. 

Models getting more confident of height rises to the North by the end of the month.

There is enough going on in the ops pre fi to make you wonder just what will actually verify come the last week of January. 

[TEITS]

Certainly hints that any atlantic influence will be shortlived. However lets not get carried away because at this stage a cold SE,ly is more likely than a cold snowy E,ly although obviously this is subject to change.

Just for fun a GEFS ensemble member brings 850s as low as -17C!

Edited January 18, 2016 by TEITS

[Nick F]

The models appear to be increasingly moving away from Atlantic mobility/zonality signal that had been touted recently, this could be down to increasingly amplified northern stream over N America, which carves out a deeper trough over eastern half which will serve to pull the trop PV away from Greenland and toward Hudson Bay. This in turn allowing pressure to build north near the UK and over Europe.

A look at 00z GEFS postage stamps at day 10 show sufficient number of members showing high pressure building north over or to the east of the U.K. to give this more amplified rather than zonal signal some weight.

This is also shown by the 00z GEFS mean at d10

shorter term, the return of milder conditions still not fully resolved, 00z GFS op not spreading milder air (8C+) northeast until Saturday, at least for England & Wales, while EC seemingly turns milder for all Friday.

Edited January 18, 2016 by Nick F

[nick sussex]

I prefer this mornings ECM solution than last nights in terms of trend.

Rather than a large Russian high we'd prefer a separate lobe developing near Scandi, the large Russian high is incredibly difficult to get far enough west.

The last time we had that scenario was I think February 2012 but even then the cold found it difficult to get far enough west into the UK.

It did effect mainland Europe with some incredibly cold conditions but for the UK the smaller high over Scandi is far better in terms of delivering.

[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 MONDAY JAN 18TH 2016

THE CURRENT GENERAL SITUATION   A trough of Low pressure over SW England will weaken and move back SW later. Another trough over Central Scotland will also weaken as it moves slowly South. A High pressure ridge will build across the UK late today and tomorrow

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

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the British Isles is around 2000ft apart from SW England where the level is nearer 4000ft today, falling later. Snowfall is most likely across Central Scotland this morning gradually dying out later.

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

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

MODELS-2 WEEK HEADLINE  Rather cold at first then becoming milder and more changeable with rain at times from later this week especially towards the North and West.

THE GFS JET STREAM FORECAST  The Jet Stream will move SE across the UK and to the East for a day or two before becoming light and insignificant for a few days from midweek. Then towards the weekend the flow moves East across the UK for a time, albeit relatively weakly before throughout the second week it is shown to be very variable in both strength and location over this side of the Atlantic.

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

GFS OPERATIONAL The GFS Operational Run today looks rather different to yesterday with High pressure to the East and SE this week proving reluctant to give way to the fronts moving in from the West at the end of the week. As they move across the UK they weaken with some rain and milder air in tow. Following on pressure builds again, first from the South-east and then the North as fine and eventually quite frosty conditions return to many areas next week. Towards the end of the run the High responsible pulls away SE with stronger SW winds and rain moving across all areas along with milder temperatures.

GFS CONTROL RUN The theme of the Control Run today also shows a lot more persistence of High pressure to the East and SE through the period this morning with rather cold and dry conditions developing this week giving way briefly with somewhat less cold SSE winds and some rain for a time towards the weekend. then as High pressure to the East builds back it becomes rather cold and mostly dry again next week before things turn milder and more unsettled again late in the run especially over the North.

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 DATA  The theme of the GFS Ensemble Clusters this morning indicate a 55% pack with mild SW winds and rain at times with High pressure to the South. 30% go for a more direct blanket of High pressure covering the UK while 10% show very unsettled and windy weather with deep Low pressure just to the North. An interesting 5% only at this stage go for a High pressure area over Iceland and Low pressure across Iberia and the Met with a strong and cold East flow across the UK.

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 the High pressure area delivering rather cold but dry conditions through the working week. Over Friday and the weekend it weakens and allows some weakening troughs NE across the UK with less cold air and some rain followed by brighter conditions especially across the South and East as High pressure remains quite close to the SE.

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

THE FAX CHARTS The Fax Charts today still shows a slow and arduous battle across or to the West and SW of the UK between mild Atlantic air and rather cold and dry air across the UK as High pressure builds and moves SE into NW Europe later in the week. Fronts to the West and SW then make some inroads into the UK by the weekend.

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

GEM GEM this morning is largely High pressure based with the centre over the North sea this week maintaining cold and mostly dry weather. Then at the end of the week and weekend the High recedes away SE for a time as a trough brings rain and less cold air for a time. Following on behind is brighter and drier weather again as pressure builds again from the South and SE. the theme next week is then for rather cold and dry weather for many again especially in the South and East as High pressure to the East extends a ridge West across the UK with any milder weather restricted to the NW.

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

NAVGEM NAVGEM today maintains it's similar theme to yesterday towards somewhat miler air making it across the UK by next weekend. In the meantime a lot of rather cold and benign weather looks likely with some frost and fog at night and occasional rain in the SW. Then next weekend a NW/SE split sets up with milder and changeable conditions in SW winds over the NW while the South and East still look mainly dry, perhaps with slight frost at night continuing in light winds but temperatures near average at least by day.

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

ECM ECM today shows a slow breakdown of High pressure to the East late this week but it does look like it may only be temporary as after a spell of rain for some pressure rebuilds to the East allowing a continental feed at times across at least the South early next week with milder Atlantic air still trying to push up against a cold block of High pressure to the East late in the run.

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

ECM 10 DAY MEAN The 10 day mean chart shows a pressure pattern which has backed west over the last day or so having Low pressure further West near Southern Greenland and pressure somewhat higher over Northern Europe. To me this suggests that more of a Southerly flow with more of a continental influence to the east and South next week is possible.

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

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The models are trending towards a somewhat shorter spell of milder winds late this week with the theme of more influence from High pressure to the East and SE next week growing too. 

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 and GFS at 99.4 pts respectively.  At 3 days ECM is leading with 97.6 pts to UKMO's 96.7 pts while GFS lags behind at 96.4 pts. At 5 days ECM leads with 89.7 pts to UKMO at 87.7 pts then GFS at 87.4 pts. Then at 8 Days ECM still leads at 66.9 pts over GFS's 64.6 pts. Finally at Day 10 ECM is ahead of GFS at 50.8 pts to 47.0 pts respectively. 

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   While last week saw massive swings between the outputs run to run we have at least this morning some common ground again which leads to there being a greater level of confidence on the general theme of the weather in the coming weeks. As we move further out of course confidence weakens but the trends are very important and I can report that within these trends today there is some interest for those looking for cold weather. In the here and now the weakening rain band in the SW and the trough delivering patchy snow in Scotland will all dissipate within the next 24 hours as the cold air wins back as High pressure slides down from the North across the UK giving most of the UK three days of cold and bright conditions with some night frosts. All output then show this High receding away onto Europe allowing a trough of Low pressure within milder SW winds to engulf the UK on Friday or Saturday. Once  passed it is increasingly shown today that pressure will build again especially across the South and East especially with High pressure building back North and maybe West too into next week. If we can get this second build of pressure to move further North over Europe then the resultant backing winds across the South would likely re-introduce a continental flow to the winds and return lower temperatures again to the South and East of the UK at least. There is plenty of indication within the models this morning that this could happen with  the GFS Operational showing High pressure developing near the North of the UK too in the second week bringing it's own theme of colder weather from that source too. While nothing particularly exciting is shown within the output to suggest snow and ice this morning the previously model runs of mild and windy weather have largely been watered down this morning in preference to perhaps the building blocks to draw something cold from the East quite soon. Let's just hope this morning's small changes are the precursor to further enhancements of this type of solution giving a spell of dry and cold weather again as a trip back to mild and wet conditions that's been hinted at of late is something I'm sure none of us want to see.  

Next Update Tuesday January 19th 2016 from 09:00

[OldMetMan]

I felt I had to comment on developments in model output this morning, even though they are tentative and a long way off yet.

There has already been some back-tracking on the forecast return of the Atlantic systems over several days, but what I have been watching with interest is the large HP off N Russia and towards the Pole. In spite of the models trying to kill it off, it's still there. In fact, the GEM is creating a new scenario this morning involving linking it to developing HP over W and NW Europe, with a significant easterly developing.

 

Actually, it bears some striking similarities to what happened in January 1947!

I can't help but think there is still too much ambivalence over the usual return to the SW flow from the models. I think we need to watch how the upper flow develops in the next few days as this could be crucial in deciding how the longer term will pan out. A big sturdy ridge extending NE, as portrayed by the GEM might seem too much to hope for but as I see things setting themselves up at present, I think it remains a distinct possibility.

 

 

[Audaxian]

Apologies for a brief interruption...

I've been watching this thread, as I find it interesting seeing how the models evolve over time. I am, however, a complete newbie at model watching so I'm just silently soaking in. I've been able to pick up what most of the acronyms in common use mean, but there's one that's stubbornly refused to reveal itself. What does "FI" stand for? Been able to figure out that it's probably something to do with longer-range models and low confidence levels as a result, but beyond that I'm lost. Anyone want to put me out of my acronym misery? (I'll probably kick myself when it turns out it was completely obvious).

[Methuselah]

Fantasy Island...