model discussion Model output discussion 11th July onwards

[ChannelThunder]

I believe this is the third night in a row I've checked the models only to see that tantalising HP pushed back yet again! This feels reminiscent of the end of June. We'll get there eventually, but will it be September by the time we do?

[Cheshire Freeze]

GFS now has the HP getting further N, more in line with other models. Pleasant days and cool nights- nothing to moan about at all

N and E Scandi shown to cool down nicely too with uppers heading towards -5. A sign autumn is on its way

Edited August 15, 2021 by CreweCold

[JayAlmeida]

GFS 18z following the trend for the initial plume to be completely wasted out in the atlantic early next week

Any heat will be in FI range on this run so in essence there is no plume. 

 

 

Edit: The closest the run gets to any warmth is on the 25/8

The decent uppers just flatten underneath us and have made little progress by bank holiday monday.

Can we just rewind back to friday nights runs please? A prime example of why you cant trust the models past 7 days out I suppose.

In the immortal words of Tommy Cooper the late August heat has gone...

Edited August 15, 2021 by JayAlmeida

[Allseasons-Si]

The gefs 18z mean is,...well,...a cracker at day ten

[Mark wheeler]

17 minutes ago, Allseasons-si said:

The gefs 18z mean is,...well,...a cracker at day ten

Yep . Lots of hyperbole going on . Let's see what transpires eh . I remain optimistic. I have to be as I go on holiday in the last week in August .

[Frosty.]

I can dig it!  

For sure, this week looks MEH but beyond that, the Gfs 0z op / GEFS 0z mean shows a marked improvement with summery weather gradually returning!!   ⛈ 
 

 

[Methuselah]

And, just when we're about to opt for hibernation, the good, old GFS 00Z comes up with something better: 

    

    

    

Je suis sans mon marbles! 

Edited August 16, 2021 by Ed Stone

[mb018538]

Here comes the next weekend washout...some very heavy/torrential rain showing up on the ECM run. 50mm in a day in some areas.

...and here's what you could have won (Thursday/Friday last week for next Sunday):

[Guest]

Lol - back to day 8-10 at least for any warm up. It’s all well and good being optimistic but that’s bought two week of decent weather to the south all year. Time to give up on summer and hope winter is kind to us, no damaging storms, no silly cold just mild, dry and the occasional spattering of rain. 
 

The GFS mean which on the face of it looks decent is now becoming heavily skewed by about 20% of the ensembles so in my opinion should be ignored.

 

UKMO along with GEM probably the best of the bunch this morning although banking on GEM effectively against all the other at day 8 would be foolish IMO. ECM takes an age for it to clear low pressure though and we need to wait for the end of the run for HP to build. 

[Captain Shortwave]

After the last couple of days, I find it strangely ironic that the ECM probably is the best offering for this coming weekend. Maybe close to 30C in the south east on Sunday ahead of a band of heavy/thundery rain.

   

 

The models do agree on a ridge building in afterwards, though given the differences prior to this, the options from a quick build up of heat or a rather cool north/north easterly are both on the table. The GEM the best longer terms, though strangely it makes very little of the preceding ridge unlike the ECM above.

[Frosty.]

For sure, the ECM 0z op becomes a bit plumey...  during the weekend and then the run ends on a HIGH note!..... ..nae bad...I can dig it!   

 

[mb018538]

On 16/08/2021 at 08:00, Captain Shortwave said:

After the last couple of days, I find it strangely ironic that the ECM probably is the best offering for this coming weekend. Maybe close to 30C in the south east on Sunday ahead of a band of heavy/thundery rain.

   

 

The models do agree on a ridge building in afterwards, though given the differences prior to this, the options from a quick build up of heat or a rather cool north/north easterly are both on the table. The GEM the best longer terms, though strangely it makes very little of the preceding ridge unlike the ECM above.

No chance of a 30c on this mornings ECM run:



Maybe 26-27c if anywhere is sunny enough depending on rain clearance etc

Edited August 16, 2021 by mb018538

[mushymanrob]

14 hours ago, Mike Poole said:

I think we are probably going to have to accept one more transitory low, before the high pressure signal reasserts itself.  GFS T180 is right back on track:

And maybe this slight delay is more consistent with the forecasted AAM rise.

Indeed a brave shout to call the end of summer, based on a slight delay to the more amplified pattern.  

Yep, this is in line with what the anomalies have consistently developed. They wont of course show transitory shortwaves, but maybe last week when they IMHO showed a northeasterly/easterly being likely with high to our near North, they were onto something as thats what most runs are showing now before high establishes next week.
Completely agree with your last line, only i wouldnt call it "brave" ....lol..

This week isnt bad, after an unsettled weekend next week and into bank holiday is shaping up to be summery/warm/dry even hot.

 

[Captain Shortwave]

On 16/08/2021 at 08:07, mb018538 said:

No chance of a 30c on this mornings ECM run:



Maybe 26-27c if anywhere is sunny enough depending on rain clearance etc

Heh quite shocking how fast that cold front moves through. I guess the only crumb is the volatility in the output might offer some improvements from this weekend onwards.. or not…

[mb018538]

On 16/08/2021 at 08:38, Captain Shortwave said:

Heh quite shocking how fast that cold front moves through. I guess the only crumb is the volatility in the output might offer some improvements from this weekend onwards.. or not…

Certainly still possible - depending on timings etc. The ECM isn't too far from being hot, but doesn't quite make it.

Tropical forcing is trying its best to promote high pressure in our patch, but with the Nina backdrop it isn't quite managing it. Troughs and upper features are managing to move in. I think the mixed messaging is playing havoc with the models, which is why we've gone from what looked like a very strong possibility of high pressure building by the weekend a few days ago, to now having low pressure moving in instead.

There still seems to be an appetite for high pressure to develop more widely through next week.....but as it's already been pushed back a few days, I won't be buying into that until its showing 3-4 days away.

[johnholmes]

My take on 500 mb happenings this morning

Monday 16 August update

Ec and a change from the previous outputs late on last week and Saturday. This being a quite deep vortex centred on 40 W and a little n of 50 N, the very slack flow from this shows a slack ridge in the Iceland area  with the next contour close by sw England, again showing ridging. They then both meander out into the European trough way east of the uk.

Noaa has no circulation of the vortex but its trough is also about 40 W and then on to the ridge seemingly centred around Iceland. Again with almost no flow over the UK, and any trough being way east. Beneath the trough it shows a –ve anomaly, very small, just 60 DM. The +ve anomaly nearest the uk is that associated with the ridge out to Iceland and shows a reasonable one of 120 DM.

Taking the two models it is probably the most promising looking pair of 500 mb anomaly charts for some considerable time. That is if you are looking for some possible warmth, not certain yet by any means, and a flow not from a northerly point, it suggests to me a 500 flow from the south rather than the west which we have had for some time. The 8-14 suggests some mobility so not a stationary set up, at least on current output.

It is the first day of the patterns shown and for a higher probability of it occurring another 2 or 3 days of such outputs is needed to give a 70-75% probability of at least 2-3 days of late summer type weather!

ECMWF/GFS DAY 8-10 MEAN 500MB HEIGHT COMPARISON

WWW.METEO.PSU.EDU

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[Blessed Weather]

A few posts moaning about this summer's weather have been moved to the Moans thread where they belong. Link below. This is the Model Output Discussion thread please. Thanks.

 

[Frosty.]

On the face of it, the ECM 0z ensemble mean indicates increasingly settled and warmer into late August!  

 

[MATTWOLVES 3]

3 hours ago, Alderc said:

Lol - back to day 8-10 at least for any warm up. It’s all well and good being optimistic but that’s bought two week of decent weather to the south all year. Time to give up on summer and hope winter is kind to us, no damaging storms, no silly cold just mild, dry and the occasional spattering of rain. 
 

The GFS mean which on the face of it looks decent is now becoming heavily skewed by about 20% of the ensembles so in my opinion should be ignored.

 

UKMO along with GEM probably the best of the bunch this morning although banking on GEM effectively against all the other at day 8 would be foolish IMO. ECM takes an age for it to clear low pressure though and we need to wait for the end of the run for HP to build. 

How dare you take Winter from us! No cold! 

Mother of all Winters hopefully  

The output is not so bad mate..yeh the Weekend as downgraded from the other day,but beyond that looks encouraging for a decent spell to coincide with the final 3rd and I've been predicting that since the beginning of Summer

 

Edited August 16, 2021 by MATTWOLVES

[Frosty.]

Quite simply, the Gem 0z is in the process of turning into a GEM!  

[Uncertainty]

The weekend Atlantic trough is trending further west and weaker after many days of the opposite trend.

EC mean 0z yesterday 

 

0z today 

The ridge stronger and slightly less negative tilt to the trough.

GFS 0z op

GFS 6z op

Similar difference between the last two gfs Ops.

Note - A weak trough is still forecast to cross somewhere over the U.K. between Saturday and Sunday, you can vaguely approximate its track on the spreads

And as pointed out above, this could bring a lot of rain.

BUT, the trend today is to weaken the trough and keep it further west for longer.
Weaken it further and it could even dive south of the U.K. leaving a dry weekend for all. A small cluster supports this outcome:

Cluster 1 takes the low over S U.K. a wet outcome for England and Wales and the trough could hang around to the S / SE early next week which could be poor for the SE

Cluster 2

Similar to the above but the trough is weaker and moves SE quicker with drier weather following behind by Monday
 The signal for HP to build in its wake is still strong.

Cluster 3

The low is kept to the far SW and, as mentioned above, could miss the U.K. altogether.

Cluster 4 

The initial push of heights is weak and thus the low passes over Scotland bringing a wet weekend mostly in the NW, the GEM shows this option but unlike yesterday improves massively after the low clears.

Later on it looks delightful for those wanting a hot end to summer

With AAM recovering, the lag of the MJO in August phase 2 and heavy ensemble / anomaly support you’d have to say the forecast for middle end next week is very supportive of dry and sunny weather. 
This weekend however, is very tricky to call...

[SqueakheartLW]

49 minutes ago, jon snow said:

Quite simply, the Gem 0z is in the process of turning into a GEM!  

Talking of the GEM look at this totally bonkers hot outlier member 4 from the 00z for 384 hours away or Wed Sep 1st 2021 at 1am.

850hpa temps here are 23.4C above Scunthorpe but the chart is for 1am so the temperatures don't look that hot but these are overnight values showing up on the 2m temp chart. It is showing a possible min value of 24.6C in Scunthorpe. Could Wed Sep 1st 2021's daytime max be threatening the all time September maximum temperature of 35.6C recorded at Bawtry, Hesley Hall (South Yorkshire) on 2nd September 1906 if this run came off?

[MATTWOLVES 3]

Some of these charts would be getting us excited come December...robust Heights to our NW.. and an ever increasing cold pool over Greenland!

In the shorter term,I'm still thinking more settled after yet another potential spoiler of a weekend...

[The Northern Ramper]

It's great to see any real burst of heat being pushed back run after run, later and later in the season.

Yes we can still hit good numbers in September and October but it will not be as oppressive as it would have been mid-August. With most of europe sizzling at one time or another i really feel like we have missed a bullet here. Phew!!

[MATTWOLVES 3]

I'm hearing on the grapevine that there's a few who are getting tired of all this day 10 improvement talk! Firstly if the models are showing a day 10 improvement,what are we meant to do? We discuss it? If it was showing constant dross at day 10...we would discuss that too! We can only comment on what is being put in front of us! Summer as been put at day 10 all season this year,not much we can do about that...but we should be used to it,because Winter is put at day 10 for us from December through till March! 

But guess what the 6z mean looks OK,and it's around day 7 this time...we are getting that day 10 gap down now

Don't shoot the messenger,blame Meteociel