Our High pressure comes under attack somewhat next week but how long and how successful will such an attack last. My morning thoughts on the 00z's attempt to throw some answers.

http://www.norton-radstockweather.co.uk/NEW-Model-Analysis(2859336).htm

Thanks martin.

Well it's a heavy burden to bear. 

Yeah, I can think of a lot worse things to have to endure!

Pretty good 12z's, for most of us it's basically dry for the next 7 days with above average 850 temps, but remember in these high pressure situations cloud amounts can vary widely and so can restrict temperatures on the ground.

http://www.wetterzentrale.de/pics/MT8_Aberdeen_ens.png

http://www.wetterzentrale.de/pics/MT8_Manchester_ens.png

http://www.wetterzentrale.de/pics/MT8_Dublin_ens.png

http://www.wetterzentrale.de/pics/MT8_London_ens.png

Low pressure to the SW has been lurking for some time and today's model output indicates how much it moves NE next week to possibly affect the UK. Each models angle on this development is the main focus of this morning's report on my website.

http://www.norton-radstockweather.co.uk/NEW-Model-Analysis(2859336).htm

On the face of it, you'd say cooler and increasingly unsettled second half of September looks likely?

http://www.wetterzentrale.de/pics/MT8_London_ens.png

Looks that way Gavin - perhaps the Atlantic gearing up for 'proper' Autumn round the corner. Be nice to experience something interesting instead of this current HP borefest which has delivered a mix of dullness and hazy sun here. It has overstayed it's welcome  

I hope so. It'll be nice to see some lightning display off the coast here at night if a low pressure settles over the UK.

roll on winter or any weather action,    all good this weather but model watching is not much fun at the moment might see some action next week as some showers are moving in from the SW, 

Hi all,

Here's today (bumper) edition of JMA Friday:

September To December With JMA Friday

http://www.gavsweathervids.com/

Remember, JFF.

Thanks Gavin, let's hope the JMA December forecast is as reliable as the August one was - i.e. wrong!  That northern blocking over Greenland could be more dominant and push the jetstream further south than last year hopefully, however not good to see that area of above average heights to the northwest of the US once again. Look forward to Sunday to see if the CFS agrees with the JMA!

Back to MO, and does look like another relatively settled week next week.

Cheers Gavin glimmer of hope there is some blocking around Greenland, this far out it could move to something in our favour.

Time will tell of course

The appearance of Edouard as a potential hurricane in mid-Atlantic means all forecasting bets for mid to late September are off until its track is clearer

Quite.

A certain forecaster whose name cannot be mentioned found that out to his cost when his August forecast was scuppered by Bertha!

Very warm later end of next week 25c given for parts of the south with high uppers cant rule a few storms either.

http://www.meteociel.fr/modeles/gfs/royaume-uni/temperatures-2m/144h.htm

http://www.meteociel.fr/modeles/gfs/royaume-uni/temperatures-2m/168h.htm

http://www.meteociel.fr/modeles/gfs/royaume-uni/850-hpa/156h.htm

 Tiny little short wave in the mix.

http://www.meteociel.fr/modeles/gfs/royaume-uni/pression/180h.htm

The consistency regarding the general area in which Edouard tracks reflects the relatively straight-forward steering currents involved. A track close to the Azores seems a good bet.

This has interesting implications for us in the UK, because at that time, we look to have relatively little going on synoptically - perhaps a weak LP drifting NE (GFS 00z), or a continuation of LP to the SW (ECM 00z). This means that our area is up for the taking, so to speak.

If Ed tracks near the Azores as depicted on most recent runs, then a ridge is likely to be promoted ahead of it, particularly if it phases with LP already located to the SW. This is a big deal, because it prevents a secondary disturbance from developing on the periphery of the main Atlantic trough and flattening the pattern - instead a new ridge is able to build NE through the UK days 8-10.

GFS then shows another spell with a cut-off low west of Iberia and a ridge through the UK while the Atlantic jet fires away well to our NW. As the cut-off low dissipates, the ridge drops south a bit and becomes what appears to be a full-blown Bartlett (there I said it!) by day 16, with an exceptionally warm scenario developing.

ECM takes a somewhat different route, dipping the Atlantic jet south towards the Azores to link with the LP down there, and producing a strong HP cell to the NE for day 10. Interestingly, Ed remains a tropical cyclone as it tracks through the Azores Islands on day 10, and its location in conjunction with the position of the dip in the jet favours a continuation of LP to the W/NW beyond that day, though perhaps a LP system could develop more to the SW again... either way it remains warmer than average across England and Wales, perhaps markedly so.

That would be quite an achievement considering that it looks likely to be very warm indeed from Wednesday next week for 4-7 days depending on which model you look at... we're talking mid-20's maximums widely across England and Wales with low to mid-teens minimums! 

The 06z GFS run... seriously, that's an extraordinary sequence of events modelled there.

What's more, the evolution to day 10 is a step towards what the ECM 00z op run showed, indicating good support.

The idea of some kind of Bartlett High late in the month and some serious heat (relative to the time of year) pushing north, akin to the closing days of September 2011, is again seen.

Of course, there's no way we can count on such a perfect sequence of events, but at least the run of mid-20's maximums starting next Wednesday has ever-stronger support both for occurence and persistence 

Just for fun... the GFS 06z run gives a rough CET estimate of 16.4*C to 28th September, matching the final figure for the record holding month of 2006. If the blowtorch at the end of the run then hung on for the final two days, the final figure would be around 16.6*C, setting a new record eight years on.

Needless to say, I would enjoy that very much - so forgive me if my analysis becomes a bit blowtorch-focused during the coming week or so! 

https://max.nwstatic.co.uk/gfsimages/gfs.20140913/12/171/h850t850eu.png

The 12z GFS op run continues the theme of having the LP to the SW dissipate W of Iberia rather than drift NE across the UK.

We're left bathing in a warm soup with temperatures in the mid to high 20's across England and Wales 

Some home grown convection features too 

https://max.nwstatic.co.uk/gfsimages/gfs.20140913/12/216/h850t850eu.png

As with previous runs, blocking then attempts to rebuild to the NE. Unlike those runs, however, this one flattens it with a powerful Atlantic storm... and yet, despite having to start anew, blocking returns with a vengence in the wake of said storm (which does little more than freshen the air down south while the north sees something more active), and yet again it builds right into Europe, akin to the last few GFS op runs in late FI.

 https://max.nwstatic.co.uk/gfsimages/gfs.20140913/12/384/h850t850eu.png

This sort of chart, with Sep-Oct 2011 written all over it, has appeared at the 15-16 day range on three operational runs in a row. That's a bit bizarre to be honest! 

We still can't place any real faith in it of course