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

[knocker]

This morning the GFS is going for a warmish SW plunge next Monday thus joining last evening's ecm for a breakdown from the west at the beginning of next week.

http://www.tropicaltidbits.com/

Edited September 28, 2015 by knocker

[knocker]

And the ecm is more or less on the same page.

 

 

[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 SEP 28TH 2015

THE CURRENT GENERAL SITUATION A High pressure area will continue to dominate the weather across the UK through the period as it drifts gradually to the NE of the UK.

 

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.

 

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 first week of this morning's forecast period. It then troughs South just to the West of the UK in a week or so time which opens the door for a strengthening flow to move East over the Atlantic to push the flow East on a much more Southerly course again across the UK in the second week.

 

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

 

GFS OPERATIONAL The GFS Operational Run today shows High pressure across Northern Britain for all of the coming week with fine and settled weather for all areas as a result with variable cloud cover. Then towards the end of next weekend pressure falls steadily and the second week comparatively becomes windy and unsettled with rain and showers developing for all as deep Low pressure to the North of the UK pushes rain bearing troughs East across the UK with temperatures near average or a little below at times.

 

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 quite supportive of the operational this morning, not just for the first week as yesterday but for the second week 2 with a much more mobile weather pattern developing across the UK from next weekend as pressure falls and a strong Westerly airflow with rain at times develops and lasts throughout the rest of the period.

 

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

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning have swung more towards a return to unsettled and windy weather again especially over the North and West of the UK for two weeks time with a much smaller group of members supporting a ridge holding on across the South.

 

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 also supports a fall in pressure next weekend as this weeks High pressure and fine weather finally slips away to the ESE next weekend. While it will stay dry through the forecast period by Day 6 (Sunday) a slowly freshening Southerly breeze will show troughs edging into Western Britain from off the Atlantic

 

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

 

THE FAX CHARTS The Fax Charts this morning show High pressure close to or over the UK up to and including Day 5 with fine and settled weather for the UK with a stiff Easterly breeze across the far South at times.

 

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

 

GEM GEM this morning shows a slightly slower transgression towards more unsettled weather leaving it until early next week before troughs edge into the UK from the West and leading to an unsettled spell later next week with wind and rain at times for all. This of course all follows this weeks fine and settled weather for the whole UK bar the very far North.

 

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

 

NAVGEM NAVGEM also supports falling pressure next weekend but from a slightly different source being the NW with an increasing SW breeze and some rain moving slowly SE across the UK following what will of been a week of fine and settled conditions under High pressure.

 

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

 

ECM ECM this morning also follows the deteriorating course of weather beginning from next weekend. In the meantime fine and settled weather prevails as High pressure remains locked over or near the UK. then at the weekend it declines to the east and a SSW flow develops with Low pressure developing to the west and moving into the UK later as quite a deep feature completely transforming the weather to quite wet and windy conditions for all by Day 10.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night illustrates a swing towards more unsettled weather with SW winds and rain at times by Dy 10.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models have strengthened their trend towards more unsettled conditions developing across the UK from the end of next weekend as all models support a fall of pressure.

 

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 tied with UKMO at 96.6 pts  while GFS lags behind at 95.7 pts. At 5 days ECM leads UKMO at 86.7 pts to 86.4 pts then GFS at 84.5 pts. Then at 8 Days ECM still leads at 58.3 pts over GFS's 53.5 pts. Finally at Day 10 ECM leads GFS at 34.4 pts to 33.9 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  It appears finally that we have a lot of agreement on when and how the current fine and settled weather will end. In the meantime we have another 5-6 days of rock solid High pressure based weather with the centre often covering the UK and ensuring a lot of fine and dry weather with variable cloud and sunny spells by day but still with chilly nights with mist and fog and a touch of frost in the less breezy North. Then it's at the weekend when pressure looks to fall and while the weekend itself looks like staying dry at the start of next week fronts finally make there move into the UK from the West or SW. Conditions then look likely to deteriorate significantly next week with rain and showers in abundance and winds becoming strong at times too as Low pressure areas make inroads across or close to the UK. Temperatures will naturally decline in the wind and rain and even when it's brighter and more showery it will feel cool in a blustery breeze from a West or NW source. It should be noted that while there is strong agreement on the weather turning unsettled next week there is plenty of disharmony on the details of this at the moment between the models so expect a continuation of further shifts of emphasis on speed and extent of change in subsequent output but with a Jet flow which looks like ratcheting up a few gears next week and on a much more Southerly track than this week there is a fair chance of the breakdown coming to pass I'm afraid. So lets enjoy the next 5-6 days as by this time next week it looks like Autumn will be taking on a more usual guise of wind and rain rather than fine and settled.

 

WORST CHART OF THE DAY 00z RUN

 

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

 

ECM at 10 Days offers us the worst chart of the day with a deep Low pressure belt stretching from the UK and to the North with another centre mid Atlantic maintaining unsettled and often wet and cool conditions looking like lasting some while as any build of pressure looks hard to acquire from the pressure distribution as shown.

 

BEST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Recm961.gif

 

The best chart of the day unsurprisingly comes from this week and today's offering is the 4 day chart from ECM which shows High pressure centred right across the UK with fine and settled weather at that time for all areas with light winds and no chance of rain.

 

Next update from 09:00 Tuesday Sep 29th 2015

[Frosty.]

The Gfs 00z shows anticyclonic conditions throughout this week with variable cloud and sunny / clear spells and feeling pleasantly warm by day with max temps in the low to mid 60's F but overnight becoming chilly with patchy mist and fog, the coldest nights across northern britain where a touch of frost is possible in rural areas. The high starts to push away eastwards through next weekend and from the start of next week it becomes progressively unsettled and cooler from the west with bouts of strong winds and persistent rain alternating with brighter but colder and showery conditions and towards the end of the run, it becomes colder still with showers turning wintry across northern hills and mountains.

Edited September 28, 2015 by Frosty.

[legritter]

The Gfs 00z shows anticyclonic conditions throughout this week with variable cloud and sunny / clear spells and feeling pleasantly warm by day with max temps in the low to mid 60's F but overnight becoming chilly with patchy mist and fog, the coldest nights across northern britain where a touch of frost is possible in rural areas. The high starts to push away eastwards through next weekend and from the start of next week it becomes progressively unsettled and cooler from the west with bouts of strong winds and persistent rain alternating with brighter but colder and showery conditions and towards the end of the run, it becomes colder still with showers turning wintry across northern hills and mountains.

Well charts paint a rosy week coming up then bingo some charts in the outlook to warm the cockles of our hearts with atlantic driven weather systems .So frosty we look forward to your wintry charts if this further outlook from todays charts come to fruition ,cheers ,Razor blades, Straws ,Prams and of course Prozack comes to mind ,cheers gang 

[Frosty.]

So frosty we look forward to your wintry charts

 

 

I'm looking forward to posting them legritter  

 

Looking at the 00z output it's becoming increasingly likely we will see a big swing to unsettled weather next week onwards which i'm pleased about as it will increase the chances of polar maritime incursions through october.

[Singularity]

So we now see the GFS det. running with unsettled conditions from 5th October as the ECM det. has been going for for a couple of days now. GFS soon irons out the meridional jet behaviour after 5th/6th October, with a broad Atlantic trough to our north anddisturbances in the flow moving west to east across the UK - very standard mid-autumn weather.

 

ECM, though, prefers to keep the jet diving a long way south, with the Atlantic train running slower but potentially delivering larger individual rain events. 

 

It seems to me that the ECM det. often has a more meridional jet in the 7+ day range than the GFS det. but is that one model being too 'flat' or the other too far the other way? I seem to recall this has been debated before on this forum, but I'm not sure it has so much since GFS had that upgrade late last January?

[Frosty.]

The Gfs 6z takes us full circle from this week's pleasantly warm anticyclonic spell to a more unsettled atlantic pattern next week, especially for the north and then back to high pressure domination towards the end of 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 Tuesday (ECM)

High pressure between 1030 to 1035mb covers all of the UK and Ireland.

 

48 Hours Wednesday (NAVGEM)

High pressure moves West while still covering all of the UK and Ireland.

 

72 Hours Thursday (FIM)

The high pressure remains in the same position continuing the settled spell of weather.

 

96 Hours Friday (FIM)

We see the high pressure move East now and backing out of the Atlantic as it starts to weaken but it will still stay settled up to the end of next week.

 

120 Hours Saturday (UKMO)

The high pressure continues to weaken and move away East from the UK and Ireland.

 

144 Hours Sunday (GFS)

As high pressure continues to move away the Western parts will see low pressure slowly taking control and may become more unsettled.

 

168 Hours Monday (NAVGEM)

Low pressure takes full control in the North by now.

 

192 Hours Tuesday (ECM)

Still a sign of high pressure building up to or near Greenland at the start of next week. Over at the UK it takes a unsettled turn with low pressure systems crossing over the UK.

 

216 & 240 Hours Wednesday and Thursday (ECM & FIM)

Low pressure still looks like it will be in control with some wet and windy weather looking likely.

 

[stodge]

Afternoon all

 

Not a lot to comment on really. The breakdown of the week's anticyclonic spell seems set:

 

http://modeles.meteociel.fr/modeles/gfs/runs/2015092806/gfs-0-174.png?6

 

Something much more Autumnal by the early part of next week.  Into deep FI and the Op run rebuilds the HP very strongly (as indeed so some of the members to be fair) while others are more cautious.

 

I think we've a fair sense of where we'll be this time next week but as always much beyond 10 days and a lot of options are still on the table.

[Frosty.]

The Gfs 12z shows a change to unsettled atlantic weather from early next week with bands of rain and strong winds seperated by brief ridging and actually most of the really unsettled weather is across the north of the uk with high pressure occasionally building in close to or across southern uk with some fine and pleasantly warm weather but the run ends unsettled with the tease of a colder shot from the northwest but the reliable timeframe is very pleasant across most of the uk with long sunny spells and temps into the high teens celsius after chilly, misty starts...enjoy this week because it looks like change is on the way next week.

Edited September 28, 2015 by Frosty.

[Frosty.]

The Ecm 12z shows low pressure taking over next week, unlike the gfs 12z there no half measures on this run, it's a much more unsettled outlook next week after this week's anticyclone.

The Ecm 12z doesn't pull any punches next week turns unsettled across all parts of the uk.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited September 28, 2015 by Frosty.

[phil nw.]

Yes this is a lovely spell of Autumn weather and it will be a pity to lose these golden days and blue skies.

Inevitably with Autumn moving on the Atlantic jet looks like awakening,indeed all the models show the block on it's last legs by the end of the week as an Atlantic trough starts to show it's hand out west.

 

ECM and UKMO at T120hrs showing the same picture as the GFS this evening.

 

 

It looks like the breakdown to frontal rain and south westerly winds will push through all areas by early next week now as the jet becomes more active across nw Europe.

 

[ANYWEATHER]

Good evening All, Some beautiful early Autumn weather along with the stunning colours of the leaves changing around this area , best since the record cold spell of 2010! Does this tell us something...???   The models have gone from there wacky and crazy output of recent days to a more traditional breakdown with rain and gales for early October!! Looking at both gfs and ecm Sunday is the pivitol day for a Big change for all........      

[Cheshire Freeze]

Good evening.

 

Well just perusing the model output this evening and in the short term it looks like we have one more fine week before a breakdown- as has been touched on already.

 

HP domination across the UK along with a fairly typical +AO and northerly jet...

 

 

 

Before something more unsettled pushes in towards the end of the weekend and into next week....

 

 

 

 

But what really interests me is the advertised tanking of the AO on both the GFS and ECM as we progress into October. I refer you to a post Bluearmy made a few days back about building blocks for the NH winter base state. Traditionally -AO Octobers are associated with an increased likelihood of a -AO winter....or so I'm led to believe by reading various pieces of research.

 

So seeing charts like this into October could potentially be good news

 

 

 

Even for the UK, encountering 2 years in a row where this theory is a bust must be seriously unlucky??

Edited September 28, 2015 by CreweCold

[Scorcher]

 

Even for the UK, encountering 2 years in a row where this theory is a bust must be seriously unlucky??

 

Or perhaps it's just a theory and not actually proven? No matter what scientific data and theories people have attempted to use to predict the weather several months down the line, no one has ever actually come up with a way of accurately predicting it more than a week or so in advance.

 

As for the ECM tonight, well it looks like it could get warmer before any breakdown with more of a flow off a warmer continent towards the weekend. At the moment we have an easterly from a rather cool source but that could change towards the end of the week. It's rather surprising seeing the 10C isotherm covering much of the UK at the moment and yet we are only managing the high teens in the afternoons.

 

Obviously a breakdown is going to come at some point but if the ECM 12Z is correct then we would have a mostly dry and warm weekend- and maybe this could be pushed back further.

[Cheshire Freeze]

Or perhaps it's just a theory and not actually proven? No matter what scientific data and theories people have attempted to use to predict the weather several months down the line, no one has ever actually come up with a way of accurately predicting it more than a week or so in advance.

 

 

 

I think the logic behind an easily disrupted or failing to organise October vortex and a resultant winter -AO is sound enough. Even though we were fairly mild, America has had two brutal winters courtesy of -AO phases. It's how the dice land. However given at present most LR models want to take the states warm this winter........(read between the lines). Anyhoo, back to model discussion.....

Edited September 28, 2015 by CreweCold

[Scorcher]

I think the logic behind an easily disrupted or failing to organise October vortex and a resultant winter -AO is sound enough. Even though we were fairly mild, America has had two brutal winters courtesy of -AO phases. It's how the dice land. However given at present most LR models want to take the states warm this winter........(read between the lines). Anyhoo, back to model discussion.....

 

I agree that there is obvious logic, and I'd like to think that we'd be able to use similar theories to predict summer prospects, but by the same token you'd think we would have fallen on the 'right side' of some of the extreme heat going into mainland Europe this summer- is that bad luck or simply the fact that we are an island? Difficult to compare the US to the UK whether winter or summer, with it being such a massive continent and more prone to extremes either way.

[Nick F]

Good evening, not posted in here for a while, but will try to more over the coming weeks. Have done a blog that has a look at the current short to medium range outlook. A breakdown of the settled weather either late weekend or early next week, 12z GFS brings the rainy breakdown Sunday across the UK, GFS holds back until Monday, but thereafter both agree on changable/unsettled conditions next week - but this similarity hides the fact that ECMWF is more amplified and warmer with the flow, with the upper trough stalling over western UK while GFS flatter trough extending into NE Europe.

 

Anyway explained in depth here: http://www.netweather.tv/index.cgi?action=news;storyid=6906;sess=

 

NOAA CPC 8-14 day prognostic H500 chart seems to side with EPS mean and ECM deterministic:

 

[Polar Maritime]

The GFS & ECMWF this morning continues to show a much cooler unsettled Pm flow from around Mon/Tue next week.

Edited September 29, 2015 by Polar Maritime

[BlueHedgehog074]

Looks as though there will be some further dry weather for the next few days as the models show High Pressure hanging around the UK with some warm days and cool nights with variable amount if cloud at times. Then, towards the weekend, the models this morning continue to show a big fight occurring:

(essentially a stand off between the Atlantic trough and... the block (European one), although it looks like the former could win).

[knocker]

Latest broad overview of the EC32 update.

 

Next week, as already indicated is trough dominated so some very unsettled weather interspersed with the odd good day. What can I say about the rest of October. Nothing sinister apparently lurking in the woodshed and essentially a trough to our NW exerting the main influence with a general westerly flow that will bring systems probably running NE across the UK. So generally unsettled, particularly in the NW, but interspersed with transitory settled periods. Temps around average. Still on track for the early blooming dafs.

[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 TUESDAY SEP 29TH 2015

 

THE CURRENT GENERAL SITUATION High pressure to the North and NE of the UK will persist with an Easterly flow over the far South and a cloudier SW flow over the far NW.

 

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 realigns much further South for a time next week. It then becomes broken and disorganized again later in week 2.

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

 

GFS OPERATIONAL The GFS Operational Run today shows High pressure across Northern Britain for the rest of this week before it declines over the weekend in response to a slowly increasing South or SW flow. Low pressure then brings a period of more unsettled conditions with some rain next week before High pressure edges back onto the scene towards the end of the period, first to the South and West and then elsewhere too as it becomes rather cold under North or NE breezes.

 

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 less supportive of a meaningful return to High pressure once the breakdown occurs this coming weekend. Instead it shows a more unstable Atlantic driven pattern with Low pressure in close attendance to the UK with it's positioning over the UK next week and then to the North with strong winds and rain at times for all late in the period

 

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

 

THE GFS CLUSTERS(14 Days) The GFS Clusters this morning show a real muddly set of options ranging from a Scandinavian anticyclone to Low pressure close to the South to a basic majority of 40% leaning towards a more mobile Atlantic driven pattern in response to Low pressure to the NW.

 

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 declining at the weekend but holding on longer over the North and East. Rain looks like reaching parts of the South and West by the end of the period.

 

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

 

THE FAX CHARTS The Fax Charts this morning show High pressure close to or over the UK up to the last day of the 5 day period when a disturbance from France brings a risk of showers by the end of the weekend to Southernmost Britain.

 

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

 

GEM GEM this morning shows High pressure breaking down at the weekend as it dissolves away East. With pressure falling the risk of rain increases markedly from the beginning of next week, first in the South and West and quickly for all as a deep Low crossing the UK is shown to bring a spell of very wet and windy weather with gales next week. Thereafter a North/South split in the weather is highlighted with the South seeing the best of any dry weather while rain at times continues across the North in a standard Autumn Westerly airflow to end the run.

 

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

 

NAVGEM NAVGEM this morning also shows falling pressure at the weekend and deep Low pressure developing over the Atlantic. This supports fairly mild but very moist Southerly winds as we move into next week with rain, heavy at times in the West but less so in the East where dry weather may hang on rather longer.

 

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

 

ECM ECM this morning also shows the fall of pressure next weekend leading into a spell of more unsettled conditions especially across the North and West. It looks like deep Low pressure over the Atlantic to start next week will be maintained to the NW of the UK thereafter with SW winds strong at times and spells of rain or showers at times for all with some drier interludes too especially in the SE where it may feel quite mild at times.

 

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

 

ECM 10 DAY MEAN The ECM 10 Day Mean Chart from last night illustrates a swing towards more unsettled weather with SW winds and rain at times on Day 10 in association with Low pressure up to the NW of Britain.

 

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

 

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The models have maintained their trend towards more unsettled conditions developing across the UK from the end of next weekend as all models continue to support a fall of pressure.

 

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 leads ECM at 86.9 pts to 86.7 pts then GFS at 84.4 pts. Then at 8 Days ECM still leads at 58.4 pts over GFS's 54.2 pts. Finally at Day 10 ECM  just leads GFS at 35.0 pts to 34.9 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  The weather still looks set to deteriorate across the British Isles, for a few at the weekend and more generally from early next week. The large Autumn anticyclone that will of lasted a week or so will begin to decline at the weekend as pressure is put upon it from both the South and West and some showery rain may reach the South at some point over the weekend which will be joined from the West by more substantial troughs and associated rains early next week. Then the methodology of how the more unsettled pattern develops is less clear cut than could be with a desire today to push the wettest conditions up towards the North and West later next week while the South and East might not see to much rain. This is entirely dependant on the Jet stream flow moving back North somewhat later which GFS hints at this morning along with the latter stages of GEM and ECM also hinting at this. Whatever happens there will be a lot of moist air around with winds from a SW quarter sucking up a lot of moisture so rainfall in the North and West at least could become quite copious. GEM also shows a major active storm system for a time next week which is fortunately in isolation at the moment but certainly would give the UK it's first widespread Autumn gales of the season. So on balance what we have this morning is slightly less focused on rain and wind than the models were showing yesterday morning and while most places look like reverting back to somewhat more unsettled conditions it maybe that the East and parts of the South won't see too much rain but in the west and NW quite a lot could occur especially over higher ground. Finally with winds looking like settling South or SW'ly from early next week temperatures should hold up reasonably well and chilly nights should generally become less significant than of late.

 

WORST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Rgem1921.gif

 

The accolade of the worst chart of the day today goes to the GEM Model with it's 192hr chart showing a deep Low across the UK with widespread gales and spells of heavy rain for all.

 

BEST CHART OF THE DAY 00z RUN

 

http://www.wetterzentrale.de/pics/Recm481.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 48hr 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 Wednesday Sep 30th 2015

[Singularity]

The jet aligns almost south to north for the first few days of next week on the GFS 06z det. run. Despite plenty of spells of rain about, a break in the weather allows temps to rise as high as 23*C across eastern parts of England on Tuesday. It's then low 20's Wednesday before another wave of warmth sees temps as high as 24*C in East Anglia on Thursday.

 

The 00z GFS det. wasn't so kind, with low pressure employing that warm, moist air to deliver a lot of rain instead. 

 

Yet it's ECM that has produced the wildest run yet again this morning. The model really seems to be keen on developing stronger areas of low pressure than GFS wherever cold and warm air collide. It doesn't have the most meridional jet this morning though, so that's something. Anyway, this would be pretty blowy for western parts, though nothing severe:

 

 

 

Further ahead in time, the GFS det. continues to blow the trumpet for a strong area of high pressure moving across from the Azores but perhaps tending to locate further NW than the one we have now. ECMs det. shows no interest in this, keeping the jet tracking south of the usual in the Atlantic and running NE through the UK, high pressure stuck across western Europe. It's the sort of setup that can wring out a lot of moisture across the UK, but without GFS on board I'm not too concerned just yet.

 

I must say, the GEFS show a marked cooling trend 7th-9th October with cool conditions persisting thereafter. We can also see a similarly strong signal for pressue to rise again - so there's a lot of support for the last two det. runs from GFS.

 

g 

 

 

It may be a different story from the ECM ensembles though. I was going to post them but the link I used to use appears to be invalid now 

[Polar Maritime]

The 6z shows some rather warm air push North over the UK for the start of next week, With the cooler/unsettled N/W flow holding off until Thu/Fri.