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

[Frosty.]

Hi John, what model are you looking at , A two week settled spell  I cant see!!???

500 mb anomaly charts

[davehsug]

Hi John, what model are you looking at , A two week settled spell  I cant see!!???

With respect Anyweather, you wouldn't see a two week settled spell if it woke up in bed next to you.    I know people in here put the slant they want on to things, but this constant hunt for the very worst in any given set of runs is beyond tedious.

[Scorcher]

With respect Anyweather, you wouldn't see a two week settled spell if it woke up in bed next to you.    I know people in here put the slant they want on to things, but this constant hunt for the very worst in any given set of runs is beyond tedious.

 

I think when he says I 'can't see' he really means 'I hope not', as the signals are pointing to a fairly prolonged settled spell.

[Cheshire Freeze]

I think when he says I 'can't see' he really means 'I hope not', as the signals are pointing to a fairly prolonged settled spell.

 

Yes at the moment they are. However, as John Hammond has just pointed out during the weather for the week ahead, tropical storms interacting with the jet stream could make current projections pointless. I've seen many, many times when HP looks to have a foothold for the foreseeable only for it to flip in just one model suite. Enjoy the next week is what I suggest and let's see where we are and what we're seeing in the projections come the weekend.

[Scorcher]

Yes at the moment they are. However, as John Hammond has just pointed out during the weather for the week ahead, tropical storms interacting with the jet stream could make current projections pointless. I've seen many, many times when HP looks to have a foothold for the foreseeable only for it to flip in just one model suite. Enjoy the next week is what I suggest and let's see where we are and what we're seeing in the projections come the weekend.

 

Of course, and things can always change quickly, but I just wanted to respond to the suggestion that the GFS is somehow correct over the other models, as the poster seemed to suggest. The 18Z has again come the way of the ECM with no breakdown shown until well into FI, however the position of the high is still not as favourable for warmth. Let's see if that changes in the morning.

[knocker]

The GFS ops is in skittish mood this morning regarding next week. Take the anomaly. It edges the Atlantic trough further east and develops the low pressure that's been hanging around southern Europe. This eventually becomes a couple lows with the HP pushed NE and eventually east. Binned.

http://www.tropicaltidbits.com/

 

 

[Polar Maritime]

That is uncertain and by no means a guarantee at this range because of how tropical storm Ida will interact with the weather pattern and there is also hints the high could head northwards around Scotland which pull in a more cooler Easterly flow thus upper air temps are more modified therefore temps are cooler more widely.

 

Yes a few runs have shown a cooler Easterly flow develop.. The GFS continues to show complications re surface detail this morning.

[Frosty.]

Of course, and things can always change quickly, but I just wanted to respond to the suggestion that the GFS is somehow correct over the other models, as the poster seemed to suggest. The 18Z has again come the way of the ECM with no breakdown shown until well into FI, however the position of the high is still not as favourable for warmth. Let's see if that changes in the morning.

The Gfs 00z is back to showing a breakdown later next week but from the south and not the atlantic. Another thing about the gfs, the high next week migrates away further north / northeast and as a trough spreads up from france, it becomes very windy with an easterly off the north sea and temps are nothing special either as you would expect, feeling cool once the winds pick up. The ukmo 00z looks much better..in my opinion.

Edited September 23, 2015 by Frosty.

[johnholmes]

Hi John, what model are you looking at , A two week settled spell  I cant see!!???

 

my usual guide to days past 5 or 6=anomaly charts

[mushymanrob]

Good Evening folks! After an unsettled week ,pressure builds for the weekend and into early next week. Good news ! The gfs model has been consistent over the last few days of a breakdown more or less from the south or south west next week around the middle of the week. Ecm in my opinion is really handling this badly as the ecm model is completely different at  T+216 12z is completely different from its 06z.   But of course the T+216 timeframe  is in la la land. But gfs in my opinion is on the money.......

 

i dont think the gfs is 'on the money' , not that im bothered either way. the noaa anomaly charts dont really support a scandinavian/northern european high , but do suggest something more in line with the ecm's version, and thats likely to last for at least two weeks... of course thats only a current prediction and isnt set in stone.

Just a quick question. What would be the chances of frost in the HP next week?

 

We still haven't got the heaters fixed in the glasshouses at work, so I'm being very attentive as to whether frost is forecast or not.

 

Thanks :-)

 

i might be wrong, but i dont think theres any frost risk. we appear to import some warmer uppers by sunday, and especially into next week IF the current ecm is proven correct.

[Frosty.]

The GEFS 00z mean shows a prolonged very pleasant anticyclonic outlook..

[knocker]

The Gefs anomaly this morning is still okay with the positive jeights at day ten but still retains the LP to the SW. No particular worries with this but in the ext period it's not looking at any HP development. It's being nothing if not persistent.

 

[Frosty.]

The Ecm 00z shows an increasingy warm and anticyclonic outlook with a prolonged very pleasant spell across the whole of the uk but with overnight / early morning mist and fog patches, towards the end of the run, the uk based high pulls west but leaves a strong ridge over the uk even by T+240 but then my eyes were drawn to developments to the north...anyway, it's a very good run..as is the ukmo 00z.   

[knocker]

The ecm also plays around with the trough to the south but the dominant factor is the HP to the west.

http://www.tropicaltidbits.com/

 

[ANYWEATHER]

Yes at the moment they are. However, as John Hammond has just pointed out during the weather for the week ahead, tropical storms interacting with the jet stream could make current projections pointless. I've seen many, many times when HP looks to have a foothold for the foreseeable only for it to flip in just one model suite. Enjoy the next week is what I suggest and let's see where we are and what we're seeing in the projections come the weekend.

Indeed. This is one of the most fickle time of year for model output........

[knocker]

Indeed. This is one of the most fickle time of year for model output........

 

That's as maybe but all one can do is try to give a fair representation of what they are saying without resorting to second guessing.

[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 23RD 2015

THE CURRENT GENERAL SITUATION A ridge of High pressure will move away East out of the UK today followed by a weakening trough later today and tonight also moving east. Tomorrow will then see a showery westerly flow across the UK with pressure rising through the day from the South.

 

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

 

MODELS-2 WEEK HEADLINE Becoming more settled after this week with sunny spells and mist and fog by night.

 

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast shows the flow on the move from currently moving South across the UK to an axis which keeps it well to the NW of the UK on a NE'ly track for some considerable time. Then longer term it breaks up and becomes ill defined as various options between members are factored in.

 

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

 

GFS OPERATIONAL The GFS Operational Run today continues to run with the theme of High pressure developing across the UK from the weekend and then moving on to become centred over Northern Europe later next week. At the same time pressure is shown to fall from the South and the resultant Easterly flow will bring cloud and showery, potentially thundery rain up into Southern Britain later next week, a process which ebbs and flows through to the end of the period with the driest and brightest weather focused more towards the North, closest to the High pressure to the North or NE.

 

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 to the operational with fine High pressure based weather up to the middle of next week before pressure falls from the South later next week with some rain at times especially towards the South and West which after several failed attempts makes it all the way across the UK later in the period as High pressure to the North and NE finally dissolves away

 

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

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning show another mixed crop today with the pendulum still on the side of more unsettled conditions likely in 14 days time probably from Low pressure based to the North or West of the UK with varying degrees of effect on the UK, NW to SE.

 

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 shows High pressure continuing to build as it forms across England at the weekend. It then floats gently out into the North Sea maintaining a strong ridge back across the UK with fine and dry weather for all in light winds.

 

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

 

THE FAX CHARTS The Fax Charts this morning show High pressure building nicely from the SW at the weekend warding off all Atlantic troughs and maintaining fine and settled weather for all once the situation has developed at the start of the weekend.

 

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

 

GEM GEM this morning shows very close resemblance to the pattern shown by GFS today in that High pressure moves steadily away to the North and NE later next week allowing an ESE flow to develop quite strongly over the South in association with quite deep Low pressure developing to the SW threatening rain into the South and West of the UK at the end of the 10 day period.

 

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

 

NAVGEM NAVGEM this morning also shows High pressure edging away to the East next week but maintaining a strong ridge over the UK with winds between east and South for all but with any threat of a push from the Atlantic Low pressure held well at bay on this run.

 

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

 

ECM ECM this morning is keeping a High pressure based theme for the UK throughout it's run this morning. there are fundamental shifts in the positioning of the High which could have implications later. As with the other output it moves to the east of the UK early next week but with a ridge maintained across the UK. It then backs West later and looks like backing off to the NW later with low pressure moving up dangerously close to the South at the same time as the door looks to be opening from a surge of cool northerly winds after the term date of this run.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night too shows High pressure stretched across the UK with almost universal support for fine and dry early Autumn weather with fine warm days and cool misty nights.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models remain little changed from yesterday with the majority showing sustained High pressure based weather across all areas with any breakdown likely to come very late in the period and quite restrictive in nature.

 

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ties with UKMO at 99.4 pts each with GFS coming in third at 99.2 pts.  At 3 days ECM again ties with UKMO at 96.5 pts while GFS lags behind at 95.7 pts. At 5 days ECM leads at 86.5 pts over UKMO at 86.4 pts then GFS at 84.4 pts. Then at 8 Days ECM still leads at 58.6 pts over GFS's 51.3 pts. Finally at Day 10 ECM leads GFS at 35.0 pts to 33.5 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  We are almost upon a period of fine and settled weather which unlike any of late looks like lasting some considerable time for most if not all of the UK. We have one more trough to clear through the UK later today and tonight before a strong pressure build from the South and SW takes shape to eliminate the showery Westerly tomorrow. By the weekend High pressure should be sat across the UK where it continues to strengthen before moving gently east out into the North Sea. Fine dry and probably sunny daytime conditions will be paid for by cool and misty potentially foggy nights which could be troublesome to clear in the mornings for some. Then we have to look further forward to see where the High moves too and what affect such a movement will have on the weather over the UK. It is encouraging to see ECM maintaining High pressure locked close to the UK right out to day 10 backed up by it's mean chart at Day 10. The operational run does show the end may be nigh after Day 10 as pressure is put on it from the South and later still the North as the High pulls back towards the NW. GFS on the other hand takes the High away to the NE rather quicker with more unsettled weather with rain at times moving up across at least the South and west later next week and eventually for all, This theme has some support from GEM too this morning with NAVGEM and UKMO looking more akin to taking the ECM route. So it looks like 4-5 days at least of universally fine conditions for the UK from Friday and probably a lot longer for most with any breakdown not showing enough support to guarantee at the moment and as long as we have ECM' fine weather in 10 days time on board which verifies best at the 10 day range I refuse to believe GFS and GEM in isolation. So lets sit back and enjoy the coming fine spell and hope that the slow clearance of overnight mists and fogs do not hamper what could be an Autumn warm and sunny period for all and not just the SE of the UK this time.

 

WORST CHART OF THE DAY 00z RUN

 

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

 

The worse chart of the day today goes to the GEM +240hr chart which shows a slow moving and deep depression just off the SW of England pumping warm and very moist SE winds carrying a lot of rain to Southern and Western Britain in particular.

 

BEST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Recm1201.gif

 

I like this chart solely because it shows a newly developed anticyclone which has recently intensified and is slow moving to bring many days of fine and settled weather to all parts of the UK and not just for some. With a gentle feed off a relatively warm Europe some pleasantly warm Autumn daytime temperatures would occur from this set-up after fog clearance.

 

Next update from 09:00 Thursday Sep 24th 2015

Edited September 23, 2015 by Gibby

[solarcycle]

Indeed. This is one of the most fickle time of year for model output........

 

I'm curious. Do you have any verification stats to back up that statement? Genuinely curious as to why you say that.

[johnholmes]

As with any time of the year the anomaly charts, for all the detractors we see on here, gives the most reliable outlook on what the general weather pattern is likely to be over the 6-15 day time scale. As with any model IF any sub tropical systems get into the North Atlantic then that prediction is likely to be wrong. So after looking at the anomaly charts I always look at the NOAA site to see what MIGHT upset the apple cart.

Currently all 3 anomaly charts I use every day of the year show an upper dige as the dominant feature from about day 5 to 15 possibly longer.Detail of course will come from the synoptic models. As to the Hurricane area on NOAA, see link below

http://www.nhc.noaa.gov/

Read their predictions on expected tracks then look at the synoptic models to see what they show.

To me, at the moment, there seems only a small probability of either of them causing any headaches in a reasonable time scale. But keep watching!

[johnholmes]

I'm curious. Do you have any verification stats to back up that statement? Genuinely curious as to why you say that.

 

Not sure of any verification to answer your question but from watching charts for many years then the period mid August into early November and sub tropical systems can upset all models. The amounts of moisture and energy they release are enormous and no one yet seems to have been able to feed the right data into the model programmes when they do occur to get a good prediction for our area. hope that helps. Others may say something different.

[bluearmy]

The 00z ECM run would have this place buzzing in winter. but we wouldn't be drawn in by the 7/10 day frames with an upper 'cold pool' advecting west and the same applies in September.

just variations around a broad theme. Does look as though the blocking wants to retrogress west a bit but that may just stick it over us in the end. nice to be musing about blocks rather than troughs.

[Summer Sun]

This mornings ECM ens shows high pressure dominating from Saturday till d10 at least

 

 

Some misty nights and mornings but very pleasant by early afternoon if you get some sunshine if the mist doesn't lift though temperatures would really struggle

Edited September 23, 2015 by Summer Sun

[chionomaniac]

I think that any prolonged setttled spell will depend on where any cut off low may end up. If you look at the jet stream profile then we have a large amplitude Rossby wave come to a shuddering halt in the Atlantic and break up. How the jet stream reforms  will determine the position of the ridge during week 2.

 

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

[knocker]

The ecm anomaly is still cooking with gas and hanging on until the towards the end of the ext period when the Atlantic trough reenters the picture with LP probably affecting at least the NW.

http://www.tropicaltidbits.com/

Edited September 23, 2015 by knocker

[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 (GEM)

Low pressure sits to the North West of the UK and will slowly move East during the day across the far North of Scotland.

 

48 Hours Friday (GFS)

Low pressure remains over most of Scotland while the rest of the UK starts to see high pressure moving in from the South West.

 

72 Hours Saturday (ECM)

High pressure around 1025mb covers most of the UK and Ireland as a low pressure system to the South West of Iceland develops.

 

96 Hours Sunday (NAVGEM)

High pressure of 1025mb now covers all of the UK and Ireland.

 

120 Hours Monday (ECM)

The high pressure starts to gain strength up to 1035mb as another low pressure system starts to develop in the Atlantic.

 

144 Hours Tuesday (ECM)

High pressure remains over the UK and moves East just slightly as the low in the Atlantic gains strength as it moves North.

 

168 Hours Wednesday (CFS)

High pressure continues to move East but still mostly covers all of the UK and Ireland.

 

192 Hours Thursday (CFS)

High pressure shows a sign of gaining even more strength and moving West.

 

216 & 240 Hours Friday and Saturday (FIM & GEM)

Most of the models at this range showed high pressure extending North into Greenland.