Model Output Discussion - 30/6/2014 Onwards - Covering July.

[mushymanrob]

Yes Mushy, The GFS has been hinting a cool down of sorts for the turn/Months end for a few days now, As you say the ECM starting to show this to, Still lots to be resolved. 

 

 

... mind you, both the ecm and gfs suggest this 'cool down' is a breif affair with the azores high drifting our way by mid nextweek.

but in all its a decent outlook for the hight of summer, not yet as good as last year (which lasted just over three weeks i believe) and certainly yet no 95, 83, 76, etc .

[Milhouse]

Very slack pressure pattern showing up for next weekend on the GFS. Still some high temperatures expected.

 

 

[Summer Sun]

UKMO remains warm but some thunderstorms would be kicking off again at t144

 

 

GFS on the other hand has high pressure closer by giving the driest weather the further south and south west you are but the 850's are lower

 

 

A case now of wait and see what ECM comes up with at t144 later on

Edited July 21, 2014 by Summer Sun

[Captain Shortwave]

The UKMO is showing the sharper pattern and creates a very interesting scenario for next weekend as a weak low becomes cut off over the UK, couple this with 850s in double figures (around 10C) then there is definitely some potential for another significant thunderstorm outbreak.

Looking at this chart then I suspect the next move would be for high pressure to topple over the low as it sinks south east into southern Europe.

The question as many times over the last few months, does the GFS have the pattern too flat and is missing this cut off low formation. It missed the one which will finally sit over the Azores so it is definitely a possibility. 

[IDO]

Ryan Maue â€@RyanMaue  6m

ECMWF reports their 12z model suite will be a "few hours late"...

 

...there wind turbine broke down!

• [*] 
  

[Man With Beard]

OK in the absence of ECM let's look at some other charts. Gem and JMA agree with a change to NWlies by Sunday, JMA not quite as ppronounced as GFS though and GEM sees little impact on the UK in terms of temps. So, according to these models, still fairly settled but just slightly cooler as we head into week 2 (we're talking maxes around 24-27c rather than 27-30 by the end of this week, so rather academic). I imagine there might just be a weak front involved but nothing particularly drastic, except for some thundery potential as heights lower.

Edited July 21, 2014 by rjbw

[phil nw.]

Still no ECM yet but GFS mean outputs looking at the fine and warm setup going into next week on the 12z run.

 

 

Little evidence of an Atlantic trough moving in at the end of the week on this run.Maybe some drizzly rain in the far nw from a weak front but essentially looking pretty dry for much of the UK.

Edited July 21, 2014 by phil nw.

[Dancerwithwings]

ECM is back on, up to 120hrs atm http://www.meteociel.fr/modeles/ecmwf.php?ech=120&mode=0&map=0&type=0&archive=0

[Captain Shortwave]

Probably stopping here as there are real differences at 4 days out with respect to the handling of thee Atlantic lows and troughs.The models all generally get to a similar solution but the ECM is very close to creating a much deeper Atlantic trough which would bring a very different solution for the weekend and beyond.

The Pub run was pretty much similar to the 12z with subtle differences here and there. Still going for 30C for Thursday-Saturday.

Edited July 21, 2014 by Captain shortwave

[Dancerwithwings]

Big differences at 144h ECM, UKMO, GFS. Blimey! i don't know what to believe come the weekend

 

Edited July 21, 2014 by Dancerwithwings

[terrier]

Think we may be seeing a change going into the weekend on the charts this morning. Looking showery with some longer outbreaks of rain. With temps dropping also. Will this be a blip or signs of a pattern change as we start to look towards latter July into August.

[mushymanrob]

Big differences at 144h ECM, UKMO, GFS. Blimey! i don't know what to believe come the weekend

 

 

oh i dunno.... all models agree that the scandinavian high will relax its influence as it drifts east over the weekend, a weak(?) cold front crosses the uk over sunday, the azores high ridges in behind it into next week bringing more settled, but cooler fresher weather. so i think the general evolution is becoming fairly apparrent, the devils in the detail.

this evolution does have support from the anomaly charts, like this which suggests the azores will ridge in after the scandinavian high departs

 

 

the general outlook though aint too bad at all for sunshine/warmth.

[Captain Shortwave]

Day 6 charts, we have the UKMO/GFS vs the ECM/GEM

 

The UKMO is very clean with building the Azores high in this weekend

cooler air never gets south of the Scottish border either.

 

GFS

Similar to the UKMO if slightly further west still very warm throughout.

 

ECM

Disagrees at the earlier timeframes and hence still digs cooler air through the UK, but this troughing is weaker than the previous run. Showery sums this up.

 

GEM

Similar to the ECM, goes Scandi trough into week 2, ECM will probably do the same. Edit - nope the Azores high gets in.

 

All in all, the GFS and UKMO are settled and very warm, the ECM offers a brief spell of less settled weather before returning to fine and warm conditions. The GEM defaults to the Scandi trough solution like it has many times this summer. Not a bad set of runs. Hopefully the UKMO or GFS are right as I'm on holiday in north Wales from the end of this week.

Edited July 22, 2014 by Captain shortwave

[Summer Sun]

The BBC weather 10 dayer last night showed 2 options for next week the lower chance was for high pressure to drifting back over the UK and thats exactly what UKMO is showing this morning with it remaining very warm for most parts of England and Wales

 

 

GFS has the centre of the high further west  but it remains very warm with just the odd shower breaking out

 

 

However ECM and GEM are not so keen on the above they both instead show some rain moving southwards across the country, ECM does slowly rise pressure during next week but GEM doesn't.

 

Its going to be a case of wait and see what future runs bring but before then we have plenty of very warm / hot weather to come though an increasing risk of thunderstorms in the south from Thursday

Edited July 22, 2014 by Summer Sun

[Man With Beard]

The outlook becoming much more mixed now for week 2. The split in the models today starts at T96: GFS has the trough around Iceland more as a wave, and is set to send it over the block (UKMO is similar)

ECM however is turning it into a cut-off low and looks set to send it under the block ... hmmmm, a not unfamiliar scenario:

Leading to the scenario described by CS earlier.

So, which one to back, if either? IMO, once the ECM tries to send energy under a block at such short range, it is 70-80% likely to happen - the only question remains is, where is the cut-off trough going to end up? It could end slap-bang over us (as above), it could even stall slightly further west. 

In any case, the trough is not particularly deep, so I imagine there will still be some sunny weather within in, perhaps afternoon thundery showers the biggest impact.

Further out, striking agreement between ECM and GFS mean at T240 - heights lower and much more chance of a westerly influence:

Studying GFS ensembles for the same time, we see many members going for a scandi trough linking back to lower heights over Iceland/Greenland. For us, it means northern areas are likely to be changeable at best, southern areas perhaps 50/50 between changeable conditions and staying under the influence of a weak ridge with temperatures remaining very warm as the end of next week approaches:

 

http://www.meteociel.fr/cartes_obs/gens_panel.php?modele=0&mode=1&ech=240

[Stormyking]

Past couple of runs now I have noticed a sign of change aswell going into the start of August, becoming a little bit unsettled and not quite so warm.

 

 

 

FI I know, but im confident with this

[terrier]

Can't post charts as on my phone at moment so apologise for that. But I must agree with stormy king here. The models now seem to be trending towards a more unsettled outlook for the start of August with a more showery and cool outlook. Can't remember last time we had a decent August in the uk. So wouldn't be surprised to see next month become more unsettled and wetter as month progresses.

[SteveB]

Past couple of runs now I have noticed a sign of change aswell going into the start of August, becoming a little bit unsettled and not quite so warm.

 

 

 

FI I know, but im confident with this

 

It's going to happen sooner or later, temps are never going to stay in the mid to high 20's for this long with out some sort of breakdown.

 

Thankfully the charts are only showing  a temporary cool down, with the North seeing temps in the high teens & the South low 20's. So nothing to drastic yet & all still over a week away.

 

The rest of this week is look warm & sunny & the weekend is looking good too. Only the slight threat of some shower drifting around mainly in the South were temps might trigger some beefy storms.

[knocker]

Well fancy that.

Edited July 22, 2014 by knocker

[MP-R]

Past couple of runs now I have noticed a sign of change aswell going into the start of August, becoming a little bit unsettled and not quite so warm.

 

 

 

FI I know, but im confident with this

 

That looks to me like warm, humid and showery with thundery downpours and thunderstorms about rather than Atlantic fronts and autumnal greyness. Perhaps a similar first weekend to August 2012 if that came off. Nevertheless, a long way in the future and similar charts have been shown for that far ahead for quite a while and keep getting pushed back so time will tell.

 

In the reliable it looks warm and sunny for the rest of this week with humidity rising and the chance of showers and storms at times as the week progresses. Great weather for high summer!

[Gael_Force]

Is that another "polar vortex" hype opportunity I see on the other side of the Pond?

[snowking]

One would suspect part and parcel of the reason for this change showing towards the end of model runs is this:

 

 

I wouldn't be hedging too many bets on this just yet with the ECMWF signal by far the strongest (and quite honestly, given it's record this side of the Atlantic over the last 2 years, it can no longer be considered as any better than any other output), but still not supported fully, though the GEFS seems fairly close to it too.

 

Whether the change is temporary or longer lasting is the question that follows, and one which we are some days yet from knowing.

 

SK

[Stormyking]

That looks to me like warm, humid and showery with thundery downpours and thunderstorms about rather than Atlantic fronts and autumnal greyness. Perhaps a similar first weekend to August 2012 if that came off. Nevertheless, a long way in the future and similar charts have been shown for that far ahead for quite a while and keep getting pushed back so time will tell.

 

In the reliable it looks warm and sunny for the rest of this week with humidity rising and the chance of showers and storms at times as the week progresses. Great weather for high summer!

What I meant to say was that, i still think it will quite warm, i think we will see more in the way low to mid 20's rather than mid to high 20's type stuff. 

 

I do agree with the fact it could be a decent set up for heavy/thundery showers, but anyways exactly its still a way out so things could still change.

For the rest of this week, the 12z is remaining very warm for this week as its rolling out still

[MP-R]

What I meant to say was that, i still think it will quite warm, i think we will see more in the way low to mid 20's rather than mid to high 20's type stuff. 

 

I do agree with the fact it could be a decent set up for heavy/thundery showers, but anyways exactly its still a way out so things could still change.

For the rest of this week, the 12z is remaining very warm for this week as its rolling out still

 

My thoughts exactly. If that came off it would produce the type of unsettled weather that I enjoy in summer. In fact similar charts can be found around July 29th last year which brought notable thunderstorms to many. Though I won't take the thread off topic so we can at least enjoy a continuation of summery conditions throughout the reliable.

[Summer Sun]

Well GFS remains keen for pressure to build back in after a slight fall later this week which will allow some thunderstorms to develop

 

 

Assuming UKMO remains more or less the same It will be interesting to see if ECM moves towards UKMO and GFS

 

EDIT UKMO holding firm with pressure on the rise once more by Sunday

 

Edited July 22, 2014 by Summer Sun