Model Output Discussions 12z 01/06/2017

[sunnijim]

4 hours ago, Frosty. said:

It's noticeable how the much trumpeted potential change to warmer more settled weather which was originally anticipated mid July is slipping back and back, now it may arrive at the tail end of July and last into August but a flick through the GEFS 6z mean doesn't show any sign of it, just the usual waxing and waning of the azores high / ridge against low pressure systems to the nw / n which means the south looks better than the north but in a generally mobile atlantic pattern.

'Much trumpeted' a phrase that applies equally on this thread to a return to unsettled and unseasonal weather, certainly in the last week it is as though the heatwave in the South (between 25c and 32c since Tuesday somewhere) is not happening.

It never really showed this longevity on the model runs leading up to it, and I have read comments on here like 'flukey heatwave'.

My point being that the Summer (apart from the mid June blip) has been something of a hot and sunny classic in the SE (so far)...All quite a surprise when you scroll back over predictions here since May!.

[Frosty.]

12 minutes ago, sunnijim said:

'Much trumpeted' a phrase that applies equally on this thread to a return to unsettled and unseasonal weather, certainly in the last week it is as though the heatwave in the South (between 25c and 32c since Tuesday somewhere) is not happening.

It never really showed this longevity on the model runs leading up to it, and I have read comments on here like 'flukey heatwave'.

My point being that the Summer (apart from the mid June blip) has been something of a hot and sunny classic in the SE (so far)...All quite a surprise when you scroll back over predictions here since May!.

Agreed, the south-east is having a great summer, like they have their very own micro climate although the week ahead shows average summer fayre across the whole of the uk, indeed, further sub-standard temperatures for northern britain yet again. In summary, the week ahead looks changeable and cooler, especially for the southeast which has been so hot. We will all see cloud and rain / showers, some heavy and thundery but with some dry and sunny spells, again especially further south / south-east.  

Edited July 9, 2017 by Frosty.

[Captain Shortwave]

Slow but steady increase in heights over the UK in the extended period, as repeated efforts from the Azores ridge to push north east slowly encourage the ridge to our east to back westwards.

      

Still uncertain, but perhaps in terms of this summer a potential make or break moment, whilst the south has had a decent summer so far, the north has lacked any real sustained warmth apart from the spel during May which was pretty much countrywide. A real chance of a proper Europe wide settled spell developing. The caveat for the level of heat depend on how clean the northwards transport of heat from Africa throughout the layers of the troposphere is towards us and northern Europe, AKA a strong Euro ridge or a weaker flabbly high with some surface lows embedded in this. This all remains to be seen,but I wouldn't be surprised to see some seriously hot low resolution runs from the GFS over the coming days.

As for the coming week, chageable but nothing dreaful, quite warm in the south at times, there is still the chance of a fine weekend yet again across England and Wales as we see the Azores high ridge in over the south of the UK.

   

GEFs suggest a fairly fine and pleasant weekend though with rain in the far north which will move slowly south on Sunday,

[Frosty.]

Noticed on the Gfs 12z, sorry I can't post charts right now but it shows high pressure across the south next weekend but it's deceptive because there is also a front with a band of rain on it heading south but weakening as it moves into the higher pressure but at least temperatures rise again further south towards the mid 20's celsius following a cooler spell, by next weekend and into week 2 it's warm again further south..still disappointingly cool and changeable further n / nw..just how much more dross does scotland have to endure this summer!?

Edited July 9, 2017 by Frosty.

[Ice Man 85]

1 minute ago, Frosty. said:

Notice on the Gfs 12z, sorry I can't post charts right now but it shows high pressure across the south next weekend but it's deceptive because there is also a front with a band of rain on it heading south but weakening as it moves into the higher pressure but at least temperatures rise again further south towards the mid 20's celsius next weekend and into week 2..still disappointingly cool and changeable further n / nw..just how much more dross does scotland have to endure this summer?

The only time I'd say "endure" would be the winter where they often get heavy and disruptive snow. As for this summer. they've been really lucky so far; barely scraped 22c after May. I'd take their summer over ours in england any day of the week.

[Fourty Point Three Degrees]

Following the awful GFS 06z, The 12z picks itself up and starts chasing those wonderful MO updates as the jet finally attempts to switch to a more SW/NE direction post 16th and offering a nice warm/hot summery looking end for all.    

[Frosty.]

Good news from the Gem 12z this evening, that seems to be reading something of the mid /longer term script with the heights appearing over Scandinavia and signs of trough disruption to the west sending heat northwards over us.

 

Edited July 9, 2017 by Frosty.

[Captain Shortwave]

Saying that, two models are perhaps taking a more progressive route forward with building high pressure in much quicker than the GEFs.

   

I guess with the ECM chucking this out then we could consider a much quicker route to settled conditions a possiblity though a low probability at the moment. ECM warm not hot at this point. Not that it is a particular worry as warm is fine.

[Singularity]

The emerging picture is one of a weakening front getting caught between two ridges this weekend, with the western one poised to move right across the UK early next week.

GEM was first to suggest the latter and now ECM has followed suit. Ensembles may be slower to shift of course, and that's assuming they do, which given the stubborn GFS is not a given, although so far this summer this GEM-ECM-GFS sequence of picking up on very warm or hot weather potential has proved oddly dependable.

This from ECM at day 10 really is the Azores-Scandi ridge scenario painted by longer-term guidance in recent times. It may well be coming together during mid-July after all but as always I must remain cautious until such developments are within 4-5 days range.

[Frosty.]

The Ecm is now starting to build a mid latitude height progression into scandinavia. The details (850 temps etc) don't matter at this stage, it's seeing the pattern evolve that matters.

Hopefully to be continued, fingers crossed. The background factors are increasing to support it.

[knocker]

Nothing new to add this evening from the ecm except just another example of the fluidity of the cool/warm pattern and a good example of the N/S split.

And the 6-10 anomaly

[ANYWEATHER]

Good Evening All , Both Ecm and Gfs show a very changeable theme , but certainly no dire summer output,. But Good news for gardens especially southern ones as they may get a watering in the days ahead changeable  but the south looks to suffer from lack of water , 1975 summer, but at least it will turn cooler this week!

[Man With Beard]

7 hours ago, Frosty. said:

It's noticeable how the much trumpeted potential change to warmer more settled weather which was originally anticipated mid July is slipping back and back, now it may arrive at the tail end of July and last into August but a flick through the GEFS 6z mean doesn't show any sign of it, just the usual waxing and waning of the azores high / ridge against low pressure systems to the nw / n which means the south looks better than the north but in a generally mobile atlantic pattern.

Frosty I'm going to attempt what some said couldn't be done and outdo your optimism!

After next weekend's mini-Azores  I push, I'm seeing a pulse of heights rising northwards through Europe sometime between 18th July and 22nd July. Can never be sure as we well know, but the most likely result for me is a raising of the jet so that it goes much further north, coupled with a height rise over Scandi deflecting troughs northwards - which is important because this prevents troughs over Scandi injecting Arctic based air into the system. THE GFS 06Z was a little spanner in the works but that aside, that's the general trend I see.

In short, a much greater chance of the whole of the UK, not just the south, being affected by warm air advecting up from Europe in the 20th-31st July period - and not a terrible chance of a serious heatwave too. 

Edited July 9, 2017 by Man With Beard

[seaside 60]

3 hours ago, sunnijim said:

'Much trumpeted' a phrase that applies equally on this thread to a return to unsettled and unseasonal weather, certainly in the last week it is as though the heatwave in the South (between 25c and 32c since Tuesday somewhere) is not happening.

It never really showed this longevity on the model runs leading up to it, and I have read comments on here like 'flukey heatwave'.

My point being that the Summer (apart from the mid June blip) has been something of a hot and sunny classic in the SE (so far)...All quite a surprise when you scroll back over predictions here since May!.

To add to that, I read that we have had 7 days over 30c and its just the  start of July.

How many years has this happened, the models have under done the temps this summer.

[MKN]

2 hours ago, seaside 60 said:

To add to that, I read that we have had 7 days over 30c and its just the  start of July.

How many years has this happened, the models have under done the temps this summer.

A decent summer was on the cards imo. look at the past 9months prior to summer. Not many major storms. Just 5 named storms over winter. Long periods dominated by high pressure and dry conditions. Summer so far is a continuation of that.

 

So far quite pleased with the assumption made here... http://extremeweather.co/2017/05/bbq-summer-increasingly-likely-for-the-uk-say-forecasters/

Edited July 9, 2017 by MKN

[TJS1998Tom]

This is more like it  (18z)

[Fourty Point Three Degrees]

is GFS 18z for real??

 

Edited July 9, 2017 by 40*C

[TJS1998Tom]

17 minutes ago, 40*C said:

is GFS 18z for real??

 

What's the highest temps that are likely to occur with this? (if it came off) 

[Fourty Point Three Degrees]

6 minutes ago, TJS1998Tom said:

What's the highest temps that are likely to occur with this? (if it came off) 

Mid 20's to 30°C and increasing each day

[A Frayed Knot]

1 hour ago, 40*C said:

is GFS 18z for real??

We are on Fire - Fire ..

 

[Ice Man 85]

16 minutes ago, A Frayed Knot said:

 

1) Its 15 days away

2) Its the GFS

3) Its the GFS 18z

4) The temps on that chart are 5-10c below what 40c is saying. Even the GFS doesn't undercook that much.

5) The ensembles don't agree with it.

[knocker]

The gfs this morning is not without interest

This week is merely a continuation of the fluid pattern which by now is very familiar so the changeable routine starting with a depression running east across southern England tomorrow, weakish fronts on Thursday  and this very typical analysis on Saturday. So periods of rain, sunny interval and temps variable around the average.

This pattern  continues into next week but changes are afoot with the Canadian lobe shifting, some amplification of the Azores in Mid Atlantic cutting off eastward transport, resulting in the trough in the eastern Atlantic deconstructing and creating another cut off low in the Iberia region. Which on the surface gives us an analysis that we have seen before this summer with the UK in a slack pressure area with the unstable low to the south, the Azores poised to ridge NE and the cooler air to the north west wanting to enter the fray. Seeing as this is going to be subject to change it seems a very good time to leave it.

Edited July 10, 2017 by knocker

[Coopsy]

9 hours ago, seaside 60 said:

To add to that, I read that we have had 7 days over 30c and its just the  start of July.

How many years has this happened, the models have under done the temps this summer.

I'd be interested to see how many days we've been above 25oC in London. It feels like most days for the past month. I also think we'd be close to breaking highest minima mean as I've not slept much in a month (mind you a new baby might have something to do with that) 

[northwestsnow]

9 minutes ago, knocker said:

The gfs this morning is not without interest

This week is merely a continuation of the fluid pattern which by now is very familiar so the changeable routine starting with a depression running east across southern England tomorrow, weakish fronts on Thursday  and this very typical analysis on Saturday. So periods of rain, sunny interval and temps variable around the average.

This pattern  continues into next week but changes are afoot with the Canadian lobe shifting, some amplification of the Azores in Mid Atlantic cutting off eastward transport, resulting in the trough in the eastern Atlantic deconstructing and creating another cut off low in the Iberia region. Which on the surface gives us an analysis that we have seen before this summer with the UK in a slack pressure area with the unstable low to the south, the Azores poised to ridge NE and the cooler air to the north west wanting to enter the fray. Seeing as this is going to be subject to change it seems a very good time to leave it.

Some of your posts really are an excellent read knocker :-)

Im beginning to have doubts about this alleged pattern change mid July onwards, there seems to be little relaxation of the Atlantic moving forward, more of what we have seen so far, ie waxing and waning of the azores high, great if you live south of Birmingham...to be fair we had a lovely warm weekend up here but i do feel for those further north, it must be horrid seeing all the warmth just a few hundred miles away.

I suspect until we see a strong euro high helping push the jet north this north south split will just continue..

[mb018538]

I'm also wondering about this. The meto quite bullishly backed warm and settled from mid month onwards for a long period of time....its apparent now that mid month isn't going to happen, and if anything it'll be the last week onwards. This is also highly dubious and far from a done deal. At present a continuation of the status quo looks most likely at the moment.