Model Output discussion 1st September 00z------->

[Frosty.]

The Gfs 6z shows a lot of fine and warm weather next week, it's not as settled as this week of course but to say it's early october next week, some of these temperatures would be more than acceptable in summer with mid 20's celsius for a time in the southeast. Most of the unsettled weather on this run is further northwest and then high pressure returns later in the run.

[Zenarcher]

Daily comparison using the GFS, ECM, UKMO, JMA, ICON, GEM, NAVGEM, NASA, CMA, FIM and the CFS all up to 240 hours along with the ECM and GFS ensembles. For each day whatever model has the most support will be shown for that time.

 

24 Hours Wednesday (ECM)

High pressure of 1035mb continues to sit over the UK and Ireland continuing the current settled spell of weather.

 

48 Hours Thursday (GEM)

The high pressure makes a shift slightly to the West but still remains over the UK and Ireland.

 

72 Hours Friday (ICON)

The high pressure begins to weaken but it still stays settled up to this point of the week.

 

96 Hours Saturday (ECM)

High pressure continues to weaken and move away from the UK and Ireland while the settled weather is expected to continue still.

 

120 Hours Sunday (FIM)

Low pressure starts to move in but Sunday should be mostly a fine day it won't be until later in the evening and over night where it will turn wet and windy.

 

144 Hours Monday (FIM)

The unsettled theme now takes control especially in the West as low pressure moves in close.

 

168 Hours Tuesday (CFS)

A large and deep low pressure system sits to the West of the UK bringing more unsettled weather.

 

192 & 216 & 240 Hours Wednesday, Thursday and Friday (CFS & ECM)

The large low pressure system is expected to slowly weaken over 2 days which will mean unsettled weather especially over the Western parts. Later on we see the arrival of more low pressure but this time Further North West.

  

[summer blizzard]

Not sure how much effect it will have on model outputs post day 5 but its worth a note that the UKMO and Euro made TD11 a substantial hurricane, GFS kills it or landfalls it (hard to tell with its setup). Quite a few models suggest that the ordinary low over Canada will deepen quite rapidly once interaction takes place.

[knocker]

Yes these two seem to be the only ones taking this scenario. As you are aware there is so much doubt about TD11 just about anything is possible  looking at the ecm 00z the main player is the large depression mid Atlantic with depressions running around it's southern flank ending like this at day 10. The wee 1002mb depression is TD11. Of course this will not materialise.

 

 

[Frosty.]

This Beautiful spell of weather will last through wed/thurs/fri with almost unbroken sunshine and temps into the high teens celsius after chilly starts with patchy mist and fog, perfect weather for the time of year, there is a suggestion the weekend will become cloudier but stay set fair. The Gfs 12z shows a very short unsettled blip early next week before high pressure builds in again through the second half of next week. Even though i'm looking forward to colder and stormier times ahead through october, this current spell of weather is really superb and I will miss it when it's gone, however, if this run is correct, high pressure will be back before you know it.   

[Frosty.]

The Ecm 12z again looks beautiful for the next 3 days with high pressure centred over the uk but the high migrates away eastwards through the weekend with pressure slowly falling across the uk. Next week looks more unsettled with low pressure in control for most of the time with a few deep lows bringing wet and windy weather but there is a window of fine weather further s/e just after next midweek as high pressure builds in across the near continent but overall, this turns into an unsettled run next week compared to the gfs.

Edited September 29, 2015 by Frosty.

[ANYWEATHER]

Hi All! Ecm shows no pressure rise later next week , Gfs  does! 

[johnholmes]

using the anomaly charts there seems little doubt that troughing will become the main feature in the 6+ day outlook. Again it looks, in spite of day to day variations between one another and themselves, that ECMWF-GFS has led the way for the change before NOAA. To me this is really interesting as over 5 years, prior to this last year, that was a very very rare event. This must be the 4th or 5th time this has happened in the past 12 months. Of course it has still not happened but it looks a 70+% bet this evening. At least the flow is from south of west (at 500mb) although with a height of about 564DM and from the Gt Lakes area and further back from eastern Russia don't expect a heat wave. It also look fairly changeable or even unsettled with a fairly brisk 500mb flow and the trough pretty close to the UK. To me the flow does not suggest any very deep lows developing close to the uk. However, keep an eye on NOAA Hurricane outputs, just one getting into the Atlantic and the models do their equivalent of 'toys out of prams'.

Edited September 29, 2015 by johnholmes

[Nouska]

using the anomaly charts there seems little doubt that troughing will become the main feature in the 6+ day outlook. Again it looks, in spite of day to day variations between one another and themselves, that ECMWF-GFS has led the way for the change before NOAA. To me this is really interesting as over 5 years, prior to this last year, that was a very very rare event. This must be the 4th or 5th time this has happened in the past 12 months. Of course it has still not happened but it looks a 70+% bet this evening. At least the flow is from south of west (at 500mb) although with a height of about 564DM and from the Gt Lakes area and further back from eastern Russia don't expect a heat wave. It also look fairly changeable or even unsettled with a fairly brisk 500mb flow and the trough pretty close to the UK. To me the flow does not suggest any very deep lows developing close to the uk. However, keep an eye on NOAA Hurricane outputs, just one getting into the Atlantic and the models do their equivalent of 'toys out of prams'.

 

Hmm....after all the naked swirls, this boy is getting dressed quickly!

 

 

Maybe a hurricane sooner rather than later.

 

http://wwwghcc.msfc.nasa.gov/cgi-bin/get-goes?satellite=GOES-E%20CONUS&lat=26&lon=-71&info=vis&zoom=1&width=1000&height=800&quality=90&type=Animation&palette=ir1.pal&numframes=20&mapcolor=gray

[summer blizzard]

Hi All! Ecm shows no pressure rise later next week , Gfs  does! 

 

All due to Tropical Storm Joaquin (all 12z models are wrong, it's already at 990mb - not forecast). GFS has it south of Greenland at day 10, Euro has it next to the UK at day 10 (not tropical by then of course), UKMO actually makes landfall in the US, so does GEM.

[knocker]

There is so much uncertainty with the track of Joaquin this is really academic but interesting how the ecm develops it even though as mentioned it's not quite behind the eight ball

http://www.tropicaltidbits.com/

 

[bluearmy]

The time of year when I revert to a NH profile when viewing the NWP.

that reveals some interesting arctic patterns predicted as crewe mentioned last evening and it seems a quickly cooling Siberia and much of n Russia as we go through the the first half of October.

[Singularity]

 

Oh look, the trough is now getting left behind as a gigantic cut-off low... the situation barely lasts more than a day but even so, that's quite a change with a much more distinct break between Monday's quick blast of wind and rain and the next spell of such weather.The potential to bring some impressively warm air our way as well. The morning runs will be interesting in this respect.

 

The picture is very uncertain thanks to the behaviour of tropical storm Joaquin, currently situated near the Bahamas and looking to become a hurricane any moment now, which the models are having a total nightmare sorting out. The GFS 18z det. has the storm tracking further west than the previous one and that seems to bring the ridge in the western N. Atlantic further west as well, increasing the scope for that low by the Azores to become cut-off at least briefly.

 

With tropical energy looking to be arriving at the high latitudes on both sides of the hemisphere within a day or two of one another(there's a large Pacific typhoon being modeled), I wonder how much of an impact that could have on the longwave patterns?

[knocker]

With the depressions running NE the 00z GFS has the breakdown quite short lived and mainly limited to the western half of the UK before quite warm and settled for two or three days. Might even get the barby out midweek but, slap the back of my legs, I mustn't get carried away on one run when fine margins are involved.

Chart weatherbell

Edited September 30, 2015 by knocker

[Frosty.]

According to the Gfs 00z op run, next week will be even warmer with temperatures into the low 20's celsius across the southern half of the uk and apart from a few showers next monday, most of next week looks fine with plenty of sunshine as pressure rises again, just the far northwest of the uk  being  brushed by atlantic frontal systems but by the end of next week it starts to turn colder from the north and become more unsettled with even some snow on the highest ground across scotland. In the meantime, the lovely anticyclonic spell continues  with dry and mainly sunny, warm days with chilly nights and a risk of patchy fog, the fine weather lasts through the weekend too.

Edited September 30, 2015 by Frosty.

[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 SEP 30TH 2015

 

THE CURRENT GENERAL SITUATION High pressure to the North and NE of the UK remains in control of the weather across the UK today and tomorrow and beyond.

 

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

 

MODELS-2 WEEK HEADLINE Mostly settled and fine at first but more unsettled and windy thereafter with rain or showers at times especially over the North and West.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the main arm and core of the flow remaining well to the North of the UK for the time being before it sinks a long way South over the Atlantic and then returns NNE across Northern and Western Britain next week. Then later in the period it becomes very variable and broken with no definitive pattern shown.

 

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

 

GFS OPERATIONAL The GFS Operational Run today has it's main message being a long delay in breaking down the current fine weather from Central and South-Eastern areas next week. Instead these areas can expect fine weather persisting for much of next week and it will feel warm in the gentle SSW winds. There will be rain at times in the North and West as Low pressure over the Atlantic edges in. It's not until week 2 when the Atlantic breaks through to all areas bringing some rain for all just for a time followed by a large drop in temperatures with a strong ENE flow over the South and a large and chilly High pressure area developing close to the North where frost and fog would become widespread at the end of the period

 

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

 

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

 

THE GFS CONTROL The theme of the GFS Control Run this morning is similar in structure with a breakdown across the West from Monday. This run also holds fine weather over the East until later next week when a trough crosses East through all areas with some rain. Temperatures then become cooler for all with the North and East still at risk of rain at times before High pressure nudges in from the West to lower temperatures to below average late in the period with some showery rain in a chilly NNE breeze to the SE while all other areas see dry and chilly weather with frost at night and also some mist and fog patches.

 

http://www.meteociel.fr/modeles/gefs_cartes.php

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning show a 65/35% split in favour of a High pressure based situation likely for the UK in 14 days. General consensus places it either to the SW or West extending a ridge across the UK. The 35% showing unsettled weather has Low pressure to the NW and West driving things with SW winds and rain at times for most.

 

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 UKMO today has also backtracked somewhat in the extent of any loss of pressure across the UK resulting in rainfall as any rain bearing systems look like only affecting the far West and NW early next week while the South and East while more cloudy than of late stays mostly dry and quite mild.

 

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

 

THE FAX CHARTS The Fax Charts this morning show High pressure declining slowly over the next 5 days but maintaining a ridge for the most parts across the UK sustaining fine and dry weather for the bulk of the UK with some warm sunshine.

 

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

 

GEM GEM this morning shows a much more volatile pattern commencing from very early next week. While High pressure and fine weather lasts until then the weather deteriorates into a wet and windy pattern next week as Low pressure makes far more progress across UK air space next week. Some very windy weather is shown at times too with near average temperatures. Some brighter intervals are shown for a time late in the run before renewed Low pressure reaches the SW at Day 10.

 

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

 

NAVGEM NAVGEM this morning is a sort of halfway house between GEM and GFS with the West  and NW certainly seeing rain at times next week, some heavy while the East and SE sees only small amounts of rain and longer dry and bright periods when it will feel quite warm in the SSW breeze

 

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

 

ECM ECM this morning has the High pressure declining from this weekend with fine weather holding on for most through the weekend before troughs swing NE across all areas with some rain for a time early next week. Following a cold front East midweek pressure rises to the South and more especially the East late next week warding off Low pressure out into the Atlantic with warm South or SE winds and dry weather affecting most of the UK to end the period

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night continues to promote Low pressure to the NW and a moist, mild and in places unstable SW airflow across the UK.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models have backtracked markedly today limiting the extent and depth of any unsettled weather across the UK and certainly the East.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead of UKMO at 99.5 pts to 99.4 with GFS closely behind at 99.3 pts.  At 3 days ECM is leading with 96.7 pts to UKMO's 96.6 pts while GFS lags behind at 95.6 pts. At 5 days UKMO ties with ECM at 86.9 pts then GFS at 84.4 pts. Then at 8 Days ECM still leads at 58.8 pts over GFS's 54.0 pts. Finally at Day 10 ECM  just leads GFS at 35.2 pts to 34.6 pts from GFS.

 

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  There seems to of been a major swing backwards from the models over the last 24 hours towards less of a breakdown likely next week across the UK especially if you live in the East and SE. There is still two or three days of the current pattern remaining with plenty of warm sunshine by day and cool misty nights and the breezy Easterly across the South should fade away from tomorrow on. Over the weekend the noticeable difference is likely to be the amounts of cloud which will increase for all and even a shower is possible in the SE. Then next week shows troughs ganging up to the West but the progress east into the UK is unsure and varied model to model. GEM is the most extreme with all areas becoming very unsettled, wet and windy but that is the extreme with much more of the output limiting the eastern extent of such troughs to the west and NW with other areas seeing a lot of fine and warm weather in balmy SSW winds. ECM does seem to show rain for all early next week albeit briefly with the same warm Southerly flow occurring later in the period of it's output. So overall things don't look as bad as they did a few days ago and this seems to be caused by the Jet stream which is now shown to make less progress South than was shown a while back and in addition pressure is shown to be lower over the Arctic and Greenland region next week which keeps Low pressure further to the North and West than would otherwise be. So in Summary the weather though turning a little more changeable next week with a little rain at times away from the far West and NW amounts shouldn't be bothersome with plenty of fine weather in between. Temperatures should see October bucking the trend of recent months as it looks like starting rather warmer then average especially by night in the SSW flow expected and while there are some colder options shown later in the period notably from the GFS camp there is nothing to suggest any widespread frosts, fogs or gales as yet this season.

 

WORST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Rgem1681.gif

 

The accolade of the worst chart of the day today goes to the GEM Model with it's 168hr chart showing a deep couple of Low pressure areas over the North of the UK with widespread gales and spells of heavy rain for all.

 

BEST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Recm241.gif

 

The best chart of the day comes as no surprise as being one close to the present as that is the only time when widespread fine weather looks likely from today's output. I have selected the ECM 24hr chart which shows High pressure orientated nicely across the UK blocking all attacks from Low pressure at that time from affecting the UK.

 

Next update from 09:00 Thursday Oct 1st 2015

Edited September 30, 2015 by Gibby

[carinthian]

Different alignments of the upper trough and high pressure zone positions on all models this morning at 144 hours. Looks like a switch back to block to hold for many. A fly in the ointment again is the developing Med Low. Of course could all change again.  Enjoy the fine weather in the British Isles. You deserve it up North !

 C

[johnholmes]

For what it is worth below is my assessment this morning after going over several times the anomaly outputs for the past 3 days.

 

Hard to see which is consistent in similar way to noaa with its change from ridging to troughing

In a way ec is more like noaa but by any means in every way=jury out really, suspect most likely is ridginge/ne of uk and troughing to w with a s of w flow much as noaa but no marked concensus at the moment.

 

The comments refer to post day 5-6

 

I suspect some of the upper air differences in the anomaly charts may well be due to Joaquin. GFS makes less of it than ECMWF in the latter stafes of the 00z run. e all know just how difficult any model of any type finds it in trying to get an accurate idea on what it will do in the North Atlantic. The latest NOAA advisory, see link below, shows it on Sunday off the east coast of America. So it is in the North Atlantic area by then.The GFS jetstream forecast shows the jet rather fragmented at that time but forcing the extHurricane/Tropical Storm to remain south. The ECMWF charts seem to push it on a more northerly track across the Atlantic.

Fascinating to see what actually happens.

 

http://www.nhc.noaa.gov/graphics_at1.shtml?5-daynl#contents

Edited September 30, 2015 by johnholmes

[knocker]

Nothing of note to add to what John has already posted except the D10 ens anomaly charts confirm the difference between the GEFs and the ecm.  The latter has ridging into the eastern Arctic, and a more pronounced trough over the UK. It continues this theme into the ext period but until the difference is resolved confidence on the evolution remains low.  En passant some abnormally high temps over Greenland and the Pole and below eastern Europe

http://www.tropicaltidbits.com/

 

[Zenarcher]

Daily comparison using the GFS, ECM, UKMO, JMA, ICON, GEM, NAVGEM, NASA, CMA, FIM and the CFS all up to 240 hours along with the ECM and GFS ensembles. For each day whatever model has the most support will be shown for that time.

 

24 Hours Thursday (JMA)

The high pressure gives a nice clear and sunny day to all of the UK and Ireland.

 

48 Hours Friday (GEM)

The high pressure starts to very slowly move away and weaken it still looks to be a nice sunny day apart from the far North of Scotland which will be more cloudier.

 

72 Hours Saturday (JMA)

Staying settled and sunny with the last bit of high pressure around although it will be cloudier over Scotland and some Northern parts.

 

96 Hours Sunday (UKMO)

It looks to be another nice day being clear and sunny for most parts but turning cloudy in the West later.

 

120 Hours Monday (CFS)

The unsettled weather arrives from the West bringing overcast conditions along with rain and strong winds especially in the North West.

 

144 & 168 & 192 Hours Tuesday, Wednesday and Friday (NAVGEM & ECM & NASA)

We now enter a period of unsettled weather as low pressure is expected to remain close by to the West of the UK.

  

 

216 & 240 Hours Saturday and Sunday (NASA & GEM)

The low pressure is expected to move over the North before it goes away completely. Other low pressure systems may also cross the UK and Ireland continuing the unsettled outlook.

 

[legritter]

Absolutely brilliant here for the end of september ,and the charts are looking good for the next 4 or 5 days .

Then all models bring in unsettled weather which will extend to most parts next week .

In the further outlook there are many options i feel looking at current charts ,with the Jet stream becoming fragmented [as john holmes mentions ]and with this in mind positioning of high pressure could throw up all sorts of synoptic situations .

Its great that we have this forum and all the info on the internet to realy enjoy our hobby ,those of us who were around back in the 60s 70 s 80 s had a very hard time trying to find out such information .

Just what is in store for us weather enthusiasts over the coming months ,its certainly great looking at all the technical info and trying to fathom out all the combinations that could be waiting for us ,well GFS ready to roll ,cheers gang   

[Yarmy]

GFS 12z op still going for Joaquin landfall. 

 

 

Will the ECM backtrack?

[solarcycle]

Cold GFS Op run. FI, outlier and all that but good to see nonetheless. 

 

[Yarmy]

GFS 12z op still going for Joaquin landfall. 

 

 

Will the ECM backtrack?

 

No, it won't.

 

[bluearmy]

Going back to the NH profile, a scan through the GFSP 06z members at the end of the run reveals the majority showing a generally -AO profile with Arctic blocking.