Model output discussion - 21st Jan Onwards

[chris55]

ECM sticking to the general theme this morning. Atlantic lows being forced south east after the ridge midweek. The cold air gets nudged a little further north and east than the 12z run but we know in these synoptic types the models often overdo the eastward progression of the warmer air. (Where's Mr Murr! He's very good at reading these)

Early days with this trend but certainly something to be positive about. 

 

[chris55]

Yes BA day 10 looking great!

 

[gottolovethisweather]

On 24/01/2016 at 7:25 PM, gottolovethisweather said:

A warm start to the forthcoming working week and then a cool down to nearer average more seasonal Temperatures come the middle to end of the week. The period from the start of February is where my interest lies right now, watch this space!

Some four days on and I'm still keeping the faith for coldies, based upon what I've heard via the BBC forecasts and through one or two of our long-term forum users in here. The main reasoning behind my confidence in the above aspect at the time was what I was seeing within the GEFS and ECM ensemble spreads at around D8 to D10 and that was a trend to colder 850s. More information is often gleaned from the ensemble spreads than by simply chasing around looking at individual operational runs in my opinion and trying to base an opinion on that. So, a continuation of a well-known atlantic based theme as we enter February yes, but one with increasing shots of polar air at times. No long-term embedded harsh cold prospects around until roughly mid-February (again also picked up by the BBC) which is hardly surprising given the state of the weather conditions over most of continental Europe, where it is equally snowless. A few reasons to be cheerful as far I can tell but for settling snow in the South we might need a bit more lady luck just yet. 

 

Edited January 28, 2016 by gottolovethisweather

[blizzard81]

Another positive this morning is that the vast majority of the gfs ensembles go cold towards the end. First time this has happened in a long time. Let's hope the ecm extended ensembles replicate this in the next hour.

[mountain shadow]

1 hour ago, Ali1977 said:

Whilst this mornings ECM is still chilly next week, it is no where near as good as last nights unfortunately. Still, chances of wintery showers Midlands northwards is still there.

Your joking right? .

The day 10 has a whole portion of the PV dropping down to the NE. Haven't seen that since 2010.

 

[Frosty.]

The Ecm 00z shows a fantastic end to the run for coldies with a prolonged Arctic Blast incoming, probably the best T+240 chart since the recent cold spell and a definite upgrade on yesterday's runs. In the meantime, the north of the UK in particular looks like having a strong blast of cold zonality late Friday and through Saturday with frequent heavy snow showers in the more northern parts of the UK with drifting on hills, Sunday looks cold in the north but with fewer showers and lighter winds. Becoming more unsettled, milder and windier further south and then Monday looks very unsettled but colder air sweeps SE for a time next week with wintry showers and night frosts and although the cold air then retreats to the far NE later next week, it returns south with a vengeance by the end of the run...expect a lot more changes and certainly don't rule out a potent cold spell through early to mid February!

[Ali1977]

4 minutes ago, mountain shadow said:

Your joking right? .

The day 10 has a whole portion of the PV dropping down to the NE. Haven't seen that since 2010.

 

I wasn't when I quoted this at 0640 before the 216/240 came out, as you say it's looking good at 240 - but nowhere near as good in the more reliable timeframe 

[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 THURSDAY JAN 28TH 2016

THE CURRENT GENERAL SITUATION   A strengthening WSW flow will develop across the UK today and tonight in association with a very deep depression crossing NE to the NW of Scotland and pushing troughs East and South down across the UK later today and tonight becoming slow moving across the South tomorrow.

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

CURRENT SNOW FORECAST AND FREEZING LEVEL OVER THE UK The freezing level across the British Isles starts the day at around 2000ft with some snowfall in the form of frequent showers across the North. The free\ing level then rises towards 7000ft across the South of England tonight and tomorrow..

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

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

MODELS-2 WEEK HEADLINE  Mostly unsettled and windy with rain or showers. Fluctuating temperatures with some snow at times over higher ground especially in the North.

THE GFS JET STREAM FORECAST  The Jet Stream forecast today shows the flow continuing to dominate the weather across the UK over the next few weeks as it remains strong throughout and blowing West to East across the UK for much of the time with a period of the second week when the flow troughs across the UK with the main portion of the flow South of the UK.

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

GFS OPERATIONAL The GFS Operational Run today shows unsettled and often windy weather persisting across many parts of the UK over the next few weeks. In the first week milder spells alternating with some short colder polar maritime blasts of showery air intervene with the milder rainy periods. Then in the second week the theme moves towards longer colder periods with showers or rain or snow in places especially over the North with shorter mild, wet and windy periods with gales. Amounts of dry weather remain restricted to weak and fast moving ridges of High pressure moving across the UK from the SW.

GFS CONTROL RUN The theme of the Control Run today shows unsettled and very windy weather too with rain at times under the same synoptic pattern as the Operational Run. In the second week the Control Run does indicate that Low pressure areas take more of a direct hit across the UK moving in an ESE direction and digging cold air down across the UK with the rain and showers turning to snow at times in places with some night frosts at times where skies clear and the winds fall briefly lighter.

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 show a strong and almost universal commitment to High pressure well to the SW of the UK in two weeks time with the UK lying under a NW flow of varying degrees with gales in places and spells of rain and more importantly colder air from more Northern latitudes than of late bringing the risk of some wintry weather across the UK at times.

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 colder weather developing next week after a weekend of gales and heavy rain in places especially over Sunday and Monday. The colder weather when it arrives looks like bringing a short spell at least of wintry showers to all areas towards the middle of next week.

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

THE FAX CHARTS The Fax Charts today show a plethora of troughs crossing the UK over the 5 day period. Various cold fronts at the start of the weekend bring rain and then colder conditions with showers turning wintry with warm fronts then struggling NE over Southern Britain with rain and snow on the leading edge late in the weekend with severe gales returning at the start of next week with a continues mix of rain and showers with snow on Northern hills.

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

GEM GEM this morning continues to project very unsettled conditions throughout the next 10 days with gales and rain at times. A drier and quieter interlude is indicated towards the middle of next week when it turns colder with some wintry showers and frost before a potentially stormy and wet period develops later next week as Low pressure parks directly over the UK on it's journey slowly East.

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

NAVGEM NAVGEM today also shows continuing wet and windy weather at times and although some milder spells remain next week looks generally somewhat colder with a drier interlude possible towards midweek before wet and windy conditions return later next week as Low pressure moves East across the UK.

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

ECM ECM today shows very windy weather for the next 4-5 days with gales and heavy rain at times especially across the North and West where some colder interludes with wintry showers look possible. Towards the middle of next week this model too shows a quieter interlude with dry, bright conditions for 24-48hrs with frost at night as High pressure moves East close to the South before things go back downhill again late next week and through the second weekend with rain and gales moving East in association with Low pressure. With colder air entrained across the UK late next week some snowfall is expected from this set-up especially over the North but perhaps the South too by the end of the run.

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

ECM 10 DAY MEAN The 10 day mean chart today continues to deepen the trough likely to lie across the UK in 10 days time. The main of the pack would indicate a variety of options of Low pressure likely over the UK with the Jet stream a long way South with a mixture of rain and showers likely almost anywhere with some cold weather and snow over the hills too.

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

NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The models this morning show continues unsettled weather with the risk of somewhat colder conditions later shown across the models today.

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 GFS and UKMO at 99.5 pts each.  At 3 days ECM is leading with 97.7 pts to UKMO's 97.0 pts while GFS lags behind at 96.7 pts. At 5 days ECM leads with 90.6 pts to UKMO at 89.0 pts and GFS at 88.6 pts. Then at 8 Days ECM has the leading spot from GFS with 67.8 pts to 67.0 pts. Finally at Day 10 ECM is ahead of GFS at 49.4 pts to 48.6 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  Though the model output this morning is not without interest for all weather lovers the main emphasis remains on the unsettled and often windy nature of our Winter weather over anything else shown again today. In the upcoming days the weather will likely be making headlines due to the strength of the wind and rainfall amounts again likely to affect the sensitive areas of the NW yet again tomorrow. Temperatures will be average to mild especially over the South through the second half of the weekend as another warm sector moves NE. Through next week the main message is that there will be further rain and showers early in the week before most output shows at least a short spell of quieter conditions around midweek when some night frosts are likely. Then later in the week renewed Low pressure from off the Atlantic looks like moving into the UK on more Southerly latitudes than recently as the Jet stream moves further South than currently. As well as the inevitable strong winds and rain that system will bring colder air will also be present in close proximity or over the UK and some of that rain may well turn to snow, more likely over the North but maybe the South too but it all looks a knife edge situation at this range and to bring anything noteworthy in terms of wintry weather the models will have to amplify the pattern more than is currently shown as I feel it could all be swept away by a maintained strong and volatile Jet flow. Nevertheless, it does hold something for cold weather fans to hang their hats on while the rest of folks remain more concerned on the amounts of rain and strong winds still to come over the next week. Leaving all else aside this morning there remains little meaningful High pressure shown within the outputs this morning maintaining this Winter as being another one of those most Low pressure based Winters when weather pattern variances are rare and short-lived.      

Next Update Friday January 29th 2016 from 09:00

[BLAST FROM THE PAST]

Okay GFS is a much better run and has definitely shifted colder. ECM is still a very good run and has only lost the channel runner as the overall theme looks in good nick.  I'll post later when at a PC but we are looking at an increasingly cold volatile setup 'within days' NOT mid Feb onwards.  I think snow will increasingly get mentioned and as it's an assault from the north, the south will be later to join in....but imo it won't be long to wait.  Indeed from an innocuous set up got a very good frost this morning.  A good start to the day from a good day yesterday.  So my positive spin to counter more (very understandable) cautious posts....the timing is still for end Jan and 1st half Feb for cold core of winter.

 

BFTP

 

[booferking]

Yea ECM is a slight downgrade everything further North there is no two ways about it but this can chance over time and revert back South again, people talk about 240hr a lot on here and how good it looks for further down the line just to put a brave face on the downgrade but i always take that far out with a pinch of salt,      

Lets hope Friday Night through to Sunday delivers for most of us first then look further ahead after that.

Edited January 28, 2016 by booferking

[Frosty.]

The Gfs 6z op is a bit Meh next week, starts very mild, especially across southern UK and then temps return to near normal for a time with a mix of sunshine and showers with some wintry on northern hills before turning a little milder later next week with the most unsettled weather in the northwest.

[snowray]

I am starting to worry that this might be just another ECM false dawn, it has done this sort of thing a few times already this Winter. I mean if it can get the pattern wrong two runs on the trot for the all important T120-T144 period then what hope does it have at T240? The GFS upgrade seems to me to have got things about right so far this Winter, the Atlantic has indeed dominated and there have been far less of the usual la la land windups from GFS that we have become accustomed to. I would like to see GFS on board before getting too excited about any cold spell.

Anyone got the performance stats I wonder for the Mid January cold snap?

[Blake]

D10 GFS, GEM and CMA... fairly similar indeed.

All indicating LP over us with high to our east slowing it down with every chance of this sinking south and heights building to NE.

 

[Gael_Force]

17 minutes ago, snowray said:

Anyone got the performance stats I wonder for the Mid January cold snap?

Just above your post: Gibby includes the stats every day in his weather model run down.

[snowray]

12 minutes ago, Gael_Force said:

Just above your post: Gibby includes the stats every day in his weather model run down.

Ahhh right you are, thanks for pointing that out.

[Frosty.]

1 hour ago, booferking said:

     

Lets hope Friday Night through to Sunday delivers for most of us first then look further ahead after that.

What are you expecting Friday night through Sunday to deliver for most of the UK and Ireland exactly? 

I can see a cold zonal blast across the far north but diddly squat for the south of the UK! 

[Rocheydub]

3 minutes ago, Frosty. said:

What are you expecting Friday night through Sunday to deliver for most of the UK and Ireland exactly? 

I can see a cold zonal blast across the far north but diddly squat for the south of the UK! 

I think this is what he's talking about:

[geminitracie]

8 minutes ago, Rocheydub said:

I think this is what he's talking about:

Isn't that rain and gales ?

[Frosty.]

6 minutes ago, Rocheydub said:

I think this is what he's talking about:

Like I said in my post above, diddly squat for the south of the UK with max temps of 6 / 7 / 8 celsius, colder further north / northwest with wintry showers bringing a mix of rain, hail, sleet and wet snow.

[winterof79]

15 minutes ago, Frosty. said:

What are you expecting Friday night through Sunday to deliver for most of the UK and Ireland exactly? 

I can see a cold zonal blast across the far north but diddly squat for the south of the UK! 

Not often we see 100%

[booferking]

11 minutes ago, Rocheydub said:

I think this is what he's talking about:

Yea thanks for that showing that chart mate maybe few members in her need to go to specksavers.

[Paul]

Frosty is making a reasonable point - if anyone is expecting lying snow away from the higher ground of northern Britain (perhaps excluding lower parts of northern Scotland) during the weekend, then they're going to be disappointed. This weekend will bring some wintriness, but we're talking sleet, wet snow, hail etc at lower levels from the midlands northward, so don't be dusting the sledges off unless you plan to climb a hill! 

[booferking]

13 minutes ago, geminitracie said:

Isn't that rain and gales ?

Yea maybe for you rain!   but really can people in here not read maybe i need to highlight the 3 crucial words that people love to overlook.  most of us

 

Now when you look at that chart provided kindly by Rocheydub you can see over 3/4 of the country is seeing some way in form of snow

Edited January 28, 2016 by booferking

[Frosty.]

1 minute ago, booferking said:

 maybe few members in her need to go to specksavers.

I suppose that was aimed at me? I am not visually challenged but I can't see anything wintry in the south where most members on here are from with max temps in the 5 / 8 celsius range! 

[Jason M]

GEFS are pretty much zonal from start to finish. A few individual charts look interesting if you run quickly through the sequences everything is moving west to east at a fair speed. ECM has been more interesting but to be honest i think the best we can hope for from this pattern is something akin to what we had last week. I still cant see anything to suggest 'deep cold' at this time. 

I thought Frosty's summary looked perfectly reasonable. 

 

Edit - IMHO be wary or the 'snow predictions' from those GFS charts. They are renowned for overplaying snow. 

 

Edited January 28, 2016 by Jason M