Some really cool conditions.

Hi James

I wonder whether the changes in the MJO that you have spoken about recently and the tropical forcings may help to finally rid us of the northern blocking that seems to have been in situ since the second half of June. There does seem to be some agreement between ECM and GFS that it may finally start to collapse next week alllowing the jet to return on a more northerly path than recently. Let's hope they are right with this.

HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 08:00 ON TUESDAY JULY 28TH 2015.

THE CURRENT GENERAL SITUATION. A depression to the NE of the UK will move away slowly East with a trough across Central and Northern areas moving SE and weakening tomorrow.

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

MODELS-2 WEEK HEADLINE Still rather changeable with some dry and bright conditions mixed with occasional rain or showers. Generally on the cool side but a few warmer interludes possible in the South.

THE GFS JET STREAM FORECAST The GFS Jet Stream Forecast continues to show the flow blowing well South over the Atlantic throughout the coming two weeks. The current arm across the South of the UK weakens and breaks up in the coming days with the flow from the Atlantic a more NE axis across the North through this weekend and next week. The flow returns West to East across the UK later in the period.

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

GFS OPERATIONAL The GFS Operational Run today shows changeable conditions continuing across the UK for most of the next two weesk. The current very cool weather should be replaced by a less cool SW flow later in the week, over the weekend and next week with the SE seeing a notable rise in temperatures to moderately warm levels for a time. Some fronts look like crossing all areas at times especially the North and West with only a little reaching the SE. The end of the run sees cool weather return to all as winds turn more West North-Westerly again.

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

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

THE GFS CONTROL The GFS Control Run sends out a broadly similar message as the operational but brings the warmth in the SE to a close rather sooner as cool Low pressure moves across the UK later next week with some wind and rainfall for all before High pressure to the SW begins to commans some control at the end of the period keeping the UK in NW winds at the end of the run.

THE GFS CLUSTERS(14 Days) The GFS Clusters at 14 days show 50% of members with Low pressure of one sort or another close to the North with Westerly winds and rain at times. The other 50% is made up of even worse conditions containing Low pressure across or just to the East of the UK with cool and wet weather for many.

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 generally quite slack pressure conditions across the UK at the weekend with Low pressure to the NW gradually extending influence back across the UK towards the end of the 6 day period with rain at times in the North and West and the risk of showers growing elsewhere. Conditions look mset to remain on the cool side overall away from the far SE.

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

THE FAX CHARTS The Fax Charts this morning look broadly similar in stance to the raw data with the advancement from the NW of Low pressure and fronts at the end of Day 5 clearly shown.

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

GEM GEM shows a distasteful run this morning with a NW/SE split at the weekend meaning showers or rain at times in the North and West and somewhat warmer and less unsettledness for the SE giving way to another unseasonably cool and wet period next week as a vigorous and deepening depression moves NE over Ireland then Scotland. As this one moves away later another one over the Atlantic looks set to bring yet more cool Atlantic winds with rain at times to end next week.

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

NAVGEM NAVGEM too shows that same depression winding itself up over NW Britain as we move into next week replacing the benign and in the SE somewhat warmer conditions for a time at the weekend.

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

ECM ECM today thankfully holds this feature further to the NW than GEM or NAVGEM giving the net result of scooping some warm and humid conditions into the South and East where it could stay largely dry later. The North and West will I'm afraid continue with the cool and unsettled theme from this feature to the NW. The run then ends strangely with hot High pressure to the East and cool High pressure to the SW with a small but significant thundery Low pressure over the SW giving some pretty wet and thundery conditions as it engages hot air to it's East.

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

ECM 10 DAY MEAN The ECM 10 Day Mean Chart today has sharpened the trough to the NW somewhat from yesterdays output suggesting more members are beginning to favour a more unstable period likely then in a broadly Westerly flow with the best of any warmth reserved for the SE only.

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

NOTABLE TREND CHANGES FROM PREVIOUS RUNS There are few definitive trends to be drawn from the models again this morning especially for Southern Britain with all options shown towards both fine and warm and cool and unsettled conditions next week. The trend is clearer for the NW as all models show continuing unsettled and cool weather here.

31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The Verification Statistics of GFS, UKMO and ECM. This morning's verification statistics show ECM leading the way at 3 days with 95.5 pts followed by UKMO at 95.0 pts and GFS at 94.2 pts. At 5 days ECM is stll king at 84.6 pts followed by UKMO at 81.6 and GFS at 81.1 pts. Then at 8 Days ECM still leads at 55.7 pts over GFS's 50.7 pts. Finally at Day 10 ECM leads GFS at 36.1 pts to 30.6 pts from GFS.
 
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.prig
 
MY THOUGHTS It's very difficult to analyze the models in a summary when there are such stark differences between them especially the further out from the present one goes. While no output shows any particularly warm or hot weather in the next week or so the SE comes quite close to high temperatures the other side of the channel at times, especially early next week. This is powered by a deep depression which some output feeds right into the heart of the UK to no doubt give some more very inclement and wet weather for some and this looks quite certain for the North. The Jury is still out on whether the South shares in this as some output including the respected ECM shows this Low further to the NW and leaving the South and SE in the warm SW feed on it's South-eastern flank while the North and West remain affected by it. Thereafter the output becomes a mish-mash of options with the GFS Clusters this morning looking particularly cool and unsavoury for all regions in 14 days time. Not too much credence should be drawn from anything definitive shown beyond 7 days at the moment and with the lack of much in the way of trend we are left to speculate on what might be from the latter end of next week. What looks more certain though is that we might move away in the South at least from the very recent coolness and rain that the North has had all Summer but there is still no concrete evidence or likelihood that any UK wide fine and hot Summer weather is likely during the period covered by the outputs today so while Southerners may continue to look back at this Summer so far as an OK and indifferent one Northerners can correctly say if todays charts verify taking us towards mid August this Summer has been a shocker for them.

Next update from 09:00 Wednesday July 28th 2015

Until James answers with his excellent analysis I will add I see little evidence of any major shift towards a Jet Stream to where it should be at this time of year within the next two weeks especially over the Atlantic. The axis will probably shift more SW to NE across the UK meaning the SE should improve temperatures wise but unlikely on a UK wide basis.

In my part of the country, today resembles and feels like the beginning of October - certainly not the end of July.

Windy had been noticable all of this summer and even on a hot spell it was too windy as well.  Today cool, overcast and windy weather are boring and forecast was meant to be more sunnier than yesterday but yesterday was fare better than today.  I never understand why we get lot of clouds when it cool compare to Death Valley last week very cool 35C temps managed to get sunny spells at 12C below average.  That a real cool spell I would be interested but not interested in fake cool weather here due to clouds.  

Hi all,

Here's today's video update;

Cool August Ideas From CFS V2

http://www.gavsweathervids.com/

First week of month looks better though...

ECM ensemble mean pressure pattern chart for day 15.

GEM offers a decent Sunday for the vast majority, GFS has the rain in NI and for the Scots though.

That's a chart for Sunday though?

Edited.  Soz!

I really hope the GEM comes off and keeps that 1015mb isobar further west cf Met O etc.

Plenty of evidence over the last few days that looking at the charts beyond a few days is rather pointless. 

True, but the output's  rubbish in that time period 

Indeed.

The Met 30 day looks average at best.

Warmth for many Oops, Im not being miserable, must try harder there...

The problem is WI that the rest of the output is rubbish - one good day or a half day or whatever in the next week is not exactly great surely? That chart is one little blip before the low pressure moves in and yes it may be nice for quite a few...for an entire day.

Trust me if the outlook was a good one I would be posting about it and be delighted....but it's not.

The weather looks like improving for the SE but remaining awful for the NW . As the Meto are saying a SE NW split as has been the case all summer. 

Have to agree, Matty.

I've long since lost count of the number of times in recent weeks where the GFS & ECM op runs have been at odds with each other in some way even within the 10 day range. Tonight's 12z runs are a case in point; the GFS tries to build HP in from Scandi at the tail end of the run, although one suspects it wouldn't last long as it doesn't look that strong. ECM is having none of it though and by the end of the run has low pressure in control of things everywhere. Also, the 240hrs chart suggests to me that even in the SE, any improvement that takes place there next week won't last for long before the unsettled stuff further NW moves to cover the whole country were it to verify as shown.

An unseasonably strong jet looks like trying its hardest to screw up another possible plume event. For the time of year, the pace and power it has on some model output is, to put it bluntly, fudging ridiculous - and you all know what fudge stands for in this context.

A 980mb low just west of the UK three days into August? You're having a laugh, surely?

...yet with that Atlantic SST profile, it all makes so much sense.

In theory, if the MJO is going to help us out at all, that should start to become apparent in charts for dates starting 8-10 days from now. If it does manage to have a significant effect, that should act to encourage a weaker jet stream across the North Atlantic, raising the potential for areas of low pressure to stall out or at least becomes slow moving while still well west of the UK.

If it doesn't, then it appears that as heights become low to our NW, the enhanced jet stream will drive us straight into an autumnal pattern - and summer 2015 will be totally, utterly fudged.

You heard it here first