Model output discussion 9th April onwards

[JayAlmeida]

2 hours ago, MATTWOLVES said:

A few of us have been mentioning it for a fair few days now regarding an improving situation,and it finally appears that the ops are smelling the Nescafe! Much better ridging in place with the Jet taking a hike further North...this would implie settled conditions and a gradual warming to become evident! Infact the chances of much warmer spells eventually....dare I say the H word?? HOT HOT HOT wouldn't rule it out towards mid month for sure.

Enjoy your week's folks and hopefully proper Summer just around the corner now! Hoorahh the lads.

Fingers crossed as these models always find a way to kick you in the nuts the closer you get to a reliable timeframe. And can I just say:

The kop has something they want you to know,

The best in the world is Bobby Firmino.

[Kentspur]

3 hours ago, mb018538 said:

I think this is the classic UK summer chart that most people would think of - Azores high building in from the SW with low pressure back towards where it should be in July. We just need this trend to start pulling back to day 9/8/7/6 through this week and we should be good for settled weather around mid-month (which is what teleconnections have progged as a potential return to better conditions since the last week of June).

Id more than take this on my bday/ St Swithuns Day be good! Still only seen any rain twice ever in my 34 years of existence though apparently it rained on my first or 2nd bday too and the rest of summer was a washout. This year Im up in Skegness for a holiday so this is perfect. Last year was a bit chilly in July when I went

Edited July 5, 2021 by Kentspur

[Methuselah]

Oh look! The GEFS 06Z ensembles are okay. But there is tad more uncertainty lurking: 

    

[JayAlmeida]

GFS 12z not looking good at day 8 possibility of more rain instead of the HP of the previous 2 runs.

[Djdazzle]

UKMO looks good going forward.

GFS 12z is so different to the 6z, I'm not convinced!

[mushymanrob]

25 minutes ago, JayAlmeida said:

GFS 12z not looking good at day 8 possibility of more rain instead of the HP of the previous 2 runs.

.......... Just because its the latest run, doesnt mean its more accurate..

[mb018538]

30 minutes ago, JayAlmeida said:

GFS 12z not looking good at day 8 possibility of more rain instead of the HP of the previous 2 runs.

Wouldn’t worry too much. GEM is still settled. If we get cross model agreement on one or the other it’s a different story, but at the moment nothing to cause alarm.

[Guest]

26 minutes ago, JayAlmeida said:

GFS 12z not looking good at day 8 possibility of more rain instead of the HP of the previous 2 runs.

Actual lol….

Personally I think UKMO is meh, upper troughs all over the place, that isn’t settling down too quickly.

GEM clearly the best of the output and manages to get high pressure in for a few days however I’d have little confidence of that coming off until it’s at least another 4 or 5 days the line. 

[Guest]

26 minutes ago, mb018538 said:

Wouldn’t worry too much. GEM is still settled. If we get cross model agreement on one or the other it’s a different story, but at the moment nothing to cause alarm.

I know what you mean but the differences are quite alarming, again I know people don’t like me saying it but again model uncertainty rarely leads to long settled spells….

Edited July 5, 2021 by Alderc

[JayAlmeida]

Yeah sorry guys I was just posting the latest GFS run in the model output discussion thread. Could very well be an outlier but interesting nonetheless.

[Mike Poole]

11 minutes ago, Alderc said:

I know what you mean but differences are alarming, again I know people don’t like me saying but again model uncertainty rarely leads to long settled spells….

I think there is some truth in this, Chris.  The models are generally less accurate in summer than winter in the northern hemisphere, that can be clearly seen in the verification stats going back decades.  However, settled spells involve anticyclones, which for the UK are probably the exception rather than the rule in summer.  And anticyclones tend to move slowly, so predictive capability in the models would tend to increase as one noses in.   

Set against that is the recent rather sudden predicted resurge in AAM though, so it isn’t quite a level playing field in this particular setup.  The GEM is a good run, but it isn’t a straightforward evolution to a high pressure dominated setup, with that cut off low floating about, and models are handling that different.  

So still uncertainty, but I think on balance one would have to favour the kind of evolution shown by the GEM over the GFS, but more runs needed.

[minus10]

1 hour ago, JayAlmeida said:

GFS 12z not looking good at day 8 possibility of more rain instead of the HP of the previous 2 runs.

Yes the 12z gfs for a lot of the time  keeps the Azores hp stuck over the...erm..Azores and further west at times. There is still so much uncertainty in my opinion that we cannot be sure of any particular outcome at present. As MP says: more runs needed....

[Mike Poole]

Good run so far from ECM, T192 and we’re almost home and hosed!

Edit, T240 and it is great:

Edited July 5, 2021 by Mike Poole

[Howie]

8 minutes ago, Mike Poole said:

Good run so far from ECM, T192 and we’re almost home and hosed!

Please be true

[Methuselah]

Nice to see that the GFS 12Z operational run is an outlier, in at least two places:

     

[Singularity]

The models seem confused regarding the tropical setup and how it will unfold in the coming week.

I thought GEFS/GFS had suddenly backed off today judging by the RMM plots, but the spatial view suggests not:

That's a nice clear eastward propagation of the MJO, just what you need to see if a more prolonged spell of high pressure is what you're after.

EPS are slightly more interested in it today but still widely scattered. Not sure what's behind the lack of clear direction. Possibly the simultaneous presence of tropical cyclones in both the West Pacific and Atlantic is having some effect but I sense there's more to it than that.

It also seems bizarre just how many sliding lows keep crossing our shores despite only a weak polar jet which by the law of averages should really be dropping lows to our west or east sometimes. As of this evening we have both ECM and GFS moving yet another one across during the weekend and into the start of next week. UKMO initially drops it just to our southwest but then grazes the south coast with it.

...but I wonder if it's so strange after all. We have the unfortunate honour of living on a sort of 'peninsula of islands' that sticks out into the maritime side of a strong cool maritime / warm continental boundary that takes shape in the summer months. That means we're right within a natural boundary along which the thermal gradient tends to be steeper, making it more likely that the polar jet will run across us when there's nothing much forcing it to do otherwise.

That, perhaps, is the underlying reason why the UK summer tends to feel like it has to be forcibly beaten into shape in order to be particularly dry and sunny.

[Mike Poole]

ECM mean very promising, T240:

And the spread gives the truth to the likely jet stream pattern, which will give the high pressure from the Azores the chance to properly ridge:

On balance, some uncertainty still, but looking ever more optimistic for summer proper within 10 days to me…

[Uncertainty]

Not sure about anything ECM related at the moment, but the latest 46 fits the mid-late July expectation framework quite neatly:

Week 2

Week 3

 

Week 4

Weeks 2, 3, 4 and 5 temps above average, except week 2 in the SE.

Whilst not in itself a guarantee of dry settled weather (renegade troughs can still loiter) the regimes continue to strongly signal blocking as the dominant regime in the weeks ahead...

The positive anomalies on the NOAA 8-14 still look on the weak side, but it still looks like a BL pattern with a benign SW flow.

 

The GEFS are unconvincing and there’s evidently a chance of ending up with more of a less inspiring showery westerly pattern.

This despite a far stronger rise in AAM.

Interesting too that the 46 manifested 3/4 weeks of settled weather from very little Eastward movement of the MJO. Not the only driver of course. Sadly I don’t have access to the GWO phase space charts.

There’s still something of a tease about the medium range output at present, most protracted HP spells I remember are forecast coherently and this one isn’t yet so  I for one am not buying it until the signal gets stronger. 

[Allseasons-Si]

Evening everyone,i hope all is well and good

it seems to me that there is another forecasting headache with regards to where the split energy of the low coming in off the Atlantic by day 6(144 hrs)so uncertainty before that me thinks

UKMO,ECM,gfs and gem...

i would much love the UKMO to come off as this shows a better outcome than the other three with trough/low out further SW,...ECM second and GEM third with the gfs last,i think there is more to this Scandi block than the ops are showing(the ops always underestimate a block of high pressure and i would suspect as we get nearer that the low will be even further SW,...just my take on it and there is no scientific evidence,just gut instinct,...talk about gut,...i need another beer

a look at the day ten EPS show that the hp cell is to our west just a tad to draw in warm/hot conditions from the south,we need this further east but i would take it

lastly there was some proper banging storms over the weekend,i would take a few warm/hot days if i was repaid with these again...

cheers gang and goodnight

 

 

Edited July 5, 2021 by Allseasons-si
typo

[damianslaw]

Entering the time of year when it becomes harder I feel to fight off the atlantic, tropical storm activity can suddenly surface - or should I say the NW-SE divide surfaces. I'm not convinced yet we will see a predominantly settled outlook despite some of today's charts.. - we shall see.. need the trends to stick for a few days yet.. not saying we won't see a settled spell, but I urge caution.

 

 

[mb018538]

Hmmmmmmm......

Not an overly convincing UKMO run today, which now develops a fully blown low rather than more of a shallow feature.

Further delays on the model output for getting high pressure in properly though. Yesterday it was looking like perhaps Thursday next week, GFS now pushes this to nearly 2 weeks time:



GEM not really there either by Friday:

[Guest]

Well the output has again gone downhill, any signs of a decent settled spell are at best 10days out and it more looks like the fourth straight weekend of complete cloud cover and precipitation. Had to see where any warmth is going to come from at this rate. At the holiday situation is much improved with last night’s announcements so going to bail out from the UK a couple of times before the end of September. 

[Methuselah]

The GFS seems to be struggling with the outlook . . . But, isn't that HP at Day 15 looking great!

    

    

    

[Guest]

ECM completely has completely capitulated this morning towards the GFS mess. Just look at the start of next week now ‍ 

[mb018538]

Looks like we're going to have to wait a bit longer to potentially get high pressure building in. A bit like the pattern change in late May, sometimes a bit of patience is required! Direction of travel is good though. Look at Saturday - Azores high retracted and no chance of anything settled here:




Fast forward to the end of next week - and finally we have a bit of movement. Trough pushing east, and the Azores high poised and ready: