Thank you Martin..

met office 30 day foecast is not sure on what is going to happen...

Same this morning as is the most likely outcome after a wet spell on Fri then better by the weekend with Sunday more HP influence from the south.

looks wet to me Jiries saturday onwards

http://www.meteociel.fr/modeles/gfs/accumulation-precipitations/81h.htm

and uk fax not much better

http://www.meteociel.fr/modeles/ukmo2.php?ech=60&carte=2000

maybe better mid week on.

Thanks Martin

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130904/12/99/h850t850eu.png

Now GFS is lifting the trough out like ECM did on it's 00z run.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130904/12/120/h850t850eu.png

...but a weak secondary low does manage to slip down across the south to bring a miserable Monday for some - a 12°C maximum is shown just west of London

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130904/12/147/h850t850eu.png

By Tuesday the default pattern of the past couple of months starts to make a comeback. When you think about it, the models have only ever shown a variant of that pattern at the 5-7 day range, in the form of a cut-off low getting stuck underneath the ridge as it builds to slightly higher latitudes than seen of late.

Part of the puzzle has been the Arctic synoptics; many runs showed heights rising there, enticing the mid-latitude ridges towards the pole, but this has now been dropped - just look at where the ECM 00z run finished:

http://www.meteociel.fr/modeles/ecmwf/runs/2013090400/ECH1-240.GIF?04-12

That's a decent PV centered over Greenland, which can drive a warm, often settled and fairly dry pattern across the south, more changeable further north.

If the PV truly ramps up at some point this month while still up across Greenland, then we could find ourselves at the mercy of some classic autumnal gales as Atlantic storms push against higher pressure across Europe.

The pattern of low heights in the Arctic and across Greenland has persisted for long enough now that an opportunity for a marked change probably isn't too far away... but by that I still mean anything from a fortnight to more than a month! I say opportunity because sometimes the various driving factors come together in such a way that the pattern is simply rebooted - we saw that in the winter of 06/07 and that sure was a blowtorch affair; I didn't have to wear my winter coat at any point, although part of that was down to me being a stubborn teenager

Good evening. Here is the report on the 12 noon outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Wednesday September 4th 2013.

All models show the ridge of high pressure over Southern and Eastern Britain currently giving way to a cold front slowly working it's way down from the NW. This feature though fairly innocuous at the moment peps up considerably tomorrow night as it makes it's way into the hot air over Central and Eastern England late tomorrow. At the same time Low pressure forms near SE England and sets up a very volatile situation with some very heavy and possible disruptive rainfall on Friday and Saturday. By Sunday the worst of the rain will probably become more showery in nature but still with some heavy bursts here and there. As well as the rain from Friday it is shown to become much cooler as well with distinct difference in the feel of things for all. Most models also show tonight the Low or by then trough moves away East from the UK on Monday as pressure is shown to rise steadily from the west or SW.

GFS shows High pressure building in steadily from the SW through the week replacing the cool and showery start to the week with dry and brighter weather with cool nights leading to the possibility of fog in the South by night. Through the extended part of the run High pressure locks firmly down on the UK with fine, settled and warm weather developing Nationwide once more with sunny spells by day and mist and fog overnight and in the mornings. At the end of the run the fog risk limits to the North as a warm SE flow develops over the South as high pressure slips further to the NE.

The GFS Ensembles show a lot of spread and confusion tonight behind the certainty of the breakdown on Friday. There are a few occasions of possibly notable rain across some areas before the trend for steadily less and less rain develops with time as High pressure makes inroads into UK air space once more.

The Jet Stream shows a sharp change in direction as it plunges South to the West of the UK later tomorrow setting up a circulation around the developing Low near SE England on Friday. After a few days the main flow powering across the Atlantic whisks this little feature away and sets up a more direct West to East flow across the UK in a week to 10 days time.

UKMO tonight shows pressure rising steadily over the UK towards the middle of next week with scattered showers in a cool NW flow as a ridge of High pressure advances in from the West soon after the close of the run.

GEM tonight has a somewhat slower progression towards High pressure later next week as several days of NW winds and fairly benign conditions affect the UK up until  midweek before a more definitive lean towards fine and warm weather looks possible towards the end of the run as High pressure builds in.

NAVGEM keeps Low pressure trapped down near the SW of England with unsettled and showery conditions maintained down here while drier and brighter conditions affect the North and east of the UK.

ECM tonight shows High pressure well established again by the middle of next week with the 10 day chart illustrating a High pressure belt all the way from mid Atlantic across Britain and East into Europe although things would be less warm than currently despite being dry and bright by day but with the risk of cool foggy nights. 

In Summary tonight the trend towards High pressure re-establishing itself again over the UK later next week is gathering pace with all but NAVGEM indicating this trend to a greater or lesser degree tonight. In the shorter term a short but possibly quite sharp unsettled period looks likely between Friday and Tuesday across many parts of the UK when we will be reminded that it is September now with more Autumnal weather very possible at times. 

Looks like the first week after my Op ( Sept 16th ) could be a nice settled one, at least I will get out .................eventually

Next week's high pressure looks a lot cooler in terms of the air associated with it, so if it does build in we should start getting the first really chilly mornings with mist and fog to begin turning the leaves...

That will suit me Gav, watch Autumn slowly arrive

Yes. same here.

Depends if it then starts to ridge in towards the continent if it can bring in warmer air.

Interesting.

http://www.jp2webdesign.co.uk/ds/gfs.htm

After some uncertainties with regards to the pattern after this weekends low pressure in recent days, it now looks as if we have some agreement for a reload of high pressure from the SW during the early part of next week.

Very Summer 2013 like.

Good morning folks. Here is the report on the midnight outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Thursday 5th September 2013.

All models continue to show a cold front moving in from the West today gradually replacing the hot and humid conditions in the SE today with very much fresher air reaching the north and west today and other areas tonight. As the cool air engages the warmth over the East the cold front will develop strongly with Low pressure forming near SE England and moving NW over the weekend with all areas experiencing rain or showers and cool winds. By Monday the low will of filled near the NW and it will clear East as a showery trough through Monday. In its wake pressure is shown to rise from the SW again as a High pressure ridge develops over the UK by midweek though with a few exceptions between the models by this point noted below.

The Fax Charts illustrate an unsettled weekend for all leading into a showery start to the new week as the Low forming near the SE tonight trundles NW and then back east by the weekend to be in the north sea by Monday. A complex array of troughs is shown in association with this feature with nowhere immune to rain on all of the covered days.

GFS is a little slower rising pressure from the West next week with Low pressure to the East still giving Eastern areas a cool and showery feed as late as Thursday before a much more slender ridge collapses over the UK on Friday followed by a trough giving the weekend a cloudier and more unsettled look about it again with some rain at times for all. It's not until we get into Week 2 that pressure rises strongly over the UK with fine and sunny weather with warm conditions by day but with cool and misty nights.

The GFS Ensembles show a sharp drop in uppers over the coming 36 hours as a cold front introduces Autumn to the UK. Thereafter conditions slowly improve again with less rainfall the deeper into the run we go, especially across the South. The strong anticyclonic theme of the operational later in the run makes this run a warm outlier in Week 2 but there is scope for improvements shown by other members to be sufficient to make for some pleasant and fine weather to be found at times almost anywhere.

The Jet Stream today is currently troughing South over the Uk as the Low over SE England forms. The cut off circulation in the Jet flow around this depression weakens over the weekend as it migrates North to join the main Northern Jet which then settles on a traditional and undulating West to East flow later close to Northern Britain.

UKMO today shows high pressure close to SW Britain next Wednesday with fine and dry weather for most having replaced the showers from early in the week. With a NW feed over the UK the weather will not be as warm as currently in the South with average temperatures, broken cloud and sunny spells the most likely.

GEM today shows Low pressure closer to the SE still by early next week which has the net result of allowing extensions of Atlantic depressions to sink SE across the UK very much diluting the effects of the ridge that other outputs show. in fact much of the week is shown to be rather cool with troughs delivering rain or showers at times especially but not exclusively to more northern and Eastern locations in average temperatures at best.

NAVGEM continues to maintain it's theory which has stuck too for days now in holding Low pressure close to Southern Britain well into the middle of next week with showers or rain at times continuing in the South whereas any High pressure ridge is only shown to affect the North.

ECM looks OK next week once the early week showers have cleared away East. With high pressure transferring East across Southern Britain midweek some fine and warm conditions would develop for a time away from the cloudier north though by the weekend things are looking a little bit more tentative as High pressure begins to seep away somewhat.

In Summary there is still the trend for High pressure to build into the UK again next week. However, there are many different guises in how the models show this likely to happen both in speed of developments as well as extent. It does appear almost guaranteed that the weekend Low will move NW over Britain and fill which allows Westerly winds developing to its South to usher in a showery trough and subsequent ridge by midweek. NAVGEM is the exception to this rule maintaining Low pressure close to the South well into next week while GEM and GFS are reluctant to bring High pressure in quite as quickly today. Instead it's down to the Euro models today who both show fine prospects under high pressure from midweek next week. Even given the charts don't show conditions being as warm or as sunny as conditions in the South and East of Britain have seen recently some very useable and benign weather is not to be sniffed at for what will be mid September.

That sounds quite OK really.

Classic UK + ECM v. GFS + GEM standoff this morning.

The former pair scoop out the trough energy relatively quickly, allowing a decent ridge to start building in from Tuesday. The Atlantic storms far to our NW pump warm air into the high and hence ECM brings another throwback to summer for a few days.

The latter pair have the trough energy distancing itself from the jet a bit more, and that leads to it lingering close to our east for some time longer, bringing below average temperatures and spells of mostly showery rain.

During this period of +ve NAO dominance, the trend has tended to be away from lingering troughs in favour of energy being carried away NE, so there's reason to be hopeful that ECM and UKMO are showing us the right path

Here's todays video update;

Summer To Autumn In Next 24hrs;

http://www.gavsweathervids.com

Big changes on the way - Next week looking quite cool.

Cheers Gav

The conkers have been falling off the Horse chestnut's trees here for the last 3 weeks or so, a sure sign Autumn is upon us.

cant see a quick trend to autumn. yes, the w/end trough will give a cold/wet day or two in large parts of the country but i suspect its just a blip in what is generally a fine outlook.

The extension of the AH towards the UK has really been a feature of conditions for some time. Looks like it may be having another go shortly and bringing more excellent weather hopefully