model discussion Model output discussion 11th July onwards

[JayAlmeida]

Nobody want to extoll the virtues of the GFS 06z then!?

Awfully quiet on here.

Yeah me neither its pretty awful TBH

[Allseasons-Si]

Both the op and control are at the bottom end of the spectrum,...relax

off to work now

have a good day everyone

[Frosty.]

I think the meteorological summer of 2021 will have it’s last fling during late August...despite some very underwhelming operational output here and there but the mean from the GEFS / ECM is still solid in supporting another summery spell, for sure, if the means looked poor, it would pretty much be game over..but they are very good currently!!! ok I’ve picked a few cherries but there’s nothing wrong with a bit of eye candy is there?  

Edited August 16, 2021 by jon snow

[Guest]

The GFS Ops run has been nowhere near the mean for several days. But as the highest resolution run it’s continuing trends can’t be ignored IMO. This particular spell of modelling from all the big models has again been handled badly and after a PP summer it’s really beginning wind me right up. 
 

 

[MATTWOLVES 3]

40 minutes ago, Alderc said:

The GFS Ops run has been nowhere near the mean for several days. But as the highest resolution run it’s continuing trends can’t be ignored IMO. This particular spell of modelling from all the big models has again been handled badly and after a PP summer it’s really beginning wind me right up. 
 

 

It's outcome can be ignored if there ain't many members backing its evolution up! The wider the scatter,the more the uncertainty. Yes its higher resolution,but it only serves as one run..Take into account that every ensemble will try and work out what's going on in the Atmosphere from a different starting point,and the more that agree on a certain outcome,the higher the confidence in that outcome! But for me these ops are throwing out continuously poor runs,and they do not seem to be getting strong ensemble support.. 

For a 5 day period I would say the ops are crucial,beyond that the use of the wider range of ensembles is a must.

I think you've wound yourself up emotionally so much this Summer,that you have now come to the conclusion,a change for the better is not possible.

 

[Mark wheeler]

Yes Navgem , you know it makes sense .

 

[mb018538]

On 16/08/2021 at 15:57, Mark wheeler said:

Yes Navgem , you know it makes sense .

 

Can always rely on the good old navgem to trundle out some eye candy in amongst the crud!  

[ChannelThunder]

A blink-and-you'll-miss-it burst of heat and thundery activity this weekend? GFS 6z is more inline with ECM, which showed exactly that. 

[SqueakheartLW]

22/08/2021 to 29/08/2021 summary

Just wanted to show the latest GFS ensemble charts for Scunthorpe starting with yesterday's 12z and ending with today's 06Z and see if there is a trend here to keep the warmer period next week or if there looks to be a general watering down of the warmer spell.

GFS12Z                                                      GFS 18z

GFS 00z                                                     GFS 06z

22/08/2021 to 29/08/2021 summary in table form as well as change from previous run

RUN      >=20C 850hpa     >=15C 850hpa     >=10C 850hpa     5C to 9.9C 850hpa

12z                  1                             3                             22                             6                       Warmer spell still on here with the 12z

18z                  1 (+0)                     8 (+5)                     20 (-2)                       3 (-3)                18z seems to be an upgrade to the heat

00z                  0 (-1)                      5 (-3)                      23 (+3)                      4 (+1)               00z seems to be a downgrade once more

06z                  0 (+0)                     2 (-3)                      23 (+0)                      7 (+3)               06z sees a further downgrade

Overall it would seem the GFS model is backing away from any serious heat next week but many options are still at or above average at 850hpa so warm weather is still looking very likely.

[Fourty Point Three Degrees]

Whats going on? Seems GFS has dropped the idea of a decent heatwave it was showing a few days ago just to continue with the same old trough and crud. 

[Tamara]

On 16/08/2021 at 14:57, MATTWOLVES said:

I think you've wound yourself up emotionally so much this Summer,that you have now come to the conclusion,a change for the better is not possible.

On 13/08/2021 at 12:31, Tamara said:

For the late August prospects for NW Europe, much hinges on both the strength and durability of recovery of momentum - with the anticipated prospect as stated previously that the low frequency walker cell will resume ascendency thereafter. and all that ensues in return of Atlantic ridge dominancy.

For me down here, always under the grip of intense sub tropical ridging right on the doorstep - its a case of just how hot, not for how long. However for NW Europe its very much a case of how (very) warm might it get and far how long in relation to the transfer of the ridge from west to east, allowing warm air advection from the south, before the pattern breaks down once again much as it did in July. This type of anticipated rinse and recycle was mooted in a previous post.

But at present, a similar reprise of the July fine spell for the UK looks a reasonable expectation.

There is nothing to change this thinking. Not even the bizarre 'law of sod' methodology which overtakes this thread.  

So, to the diagnostic.The GWO, subject to 2 day lag, has been orbiting to low angular momentum phases, circa Phase 2,  following the downward momentum drift that began in late July - not coincidentally the time that the fine, very warm spell broke down in the UK and other parts of NW Europe.

The 40 day phase plot clearly depicts the ascendency of momentum during the first half to two thirds of July, and the steady improvement from the unsettled start to the month to that late month breakdown.

Despite this, there remains the opportunity for a third fine summer spell c/o ridging into the last phase of this month for NW Europe to see official summer out in a way that it began. As suggested in the previous post, its a case to what extent the high frequency tropical wave can, temporarily, diffuse the underlying Nina-esque standing wave which continues to develop as the Pacific maintains upwelling effects of cooler water to the surface.

The positioning of the ridging clearly important to how much warmth can be generated through pulling up air from the south (its the hottest part of the summer locally here in SW Europe)  There is not a large window for potential heat in Northern Europe- based on the inherent tendency this summer for retrogressive upstream forcing. In this sense, shortfall of tropical forcing would readily see the ridging adjusting to retract once more to the Atlantic - and with a lot more La Nina to come in the remainder of 2021, the coming autumn looks to shape up maybe along the path of one like 2017 which featured a lot of Atlantic ridging through September.

Sending some summer vibes to punch through the grey skies x :  

:

 

 

 

 

[MATTWOLVES 3]

UKMO into day 7 perhaps clearing the low SE

Edited August 16, 2021 by MATTWOLVES

[sheikhy]

Fantastic ukmo run for this weekend!!very warm and sunny!!!gfs seems to be upgrading with each run as well and moving towards ecm and ukmo!!

[mb018538]

On 16/08/2021 at 17:23, sheikhy said:

Fantastic ukmo run for this weekend!!very warm and sunny!!!gfs seems to be upgrading with each run as well and moving towards ecm and ukmo!!

 

I can guarantee you that chart isn’t warm and sunny for a good portion of the southern half of the UK…GFS has this upper low crossing too, which brings lots of heavy rain:

[Mike Poole]

GEM the pick this afternoon at T168:

Much better than GFS which has the low to the SE, and then the high drifts too far north.

[summer blizzard]

GFS has moved towards retreogression vs the GEM model building east.

[Guest]

33 minutes ago, mb018538 said:

 

I can guarantee you that chart isn’t warm and sunny for a good portion of the southern half of the UK…GFS has this upper low crossing too, which brings lots of heavy rain:

I don’t understand why so many people post charts say they look good without looking at the underlying details only for them to be crap. 

[Guest]

3 hours ago, MATTWOLVES said:

It's outcome can be ignored if there ain't many members backing its evolution up! The wider the scatter,the more the uncertainty. Yes its higher resolution,but it only serves as one run..Take into account that every ensemble will try and work out what's going on in the Atmosphere from a different starting point,and the more that agree on a certain outcome,the higher the confidence in that outcome! But for me these ops are throwing out continuously poor runs,and they do not seem to be getting strong ensemble support.. 

For a 5 day period I would say the ops are crucial,beyond that the use of the wider range of ensembles is a must.

I think you've wound yourself up emotionally so much this Summer,that you have now come to the conclusion,a change for the better is not possible.

 

I don’t fully agree as a few times quite recently, especially in summer Ops runs from ECM & GFS have gone completely against their own ensembles and deliver. That’s happened with both hot spells as well as distinctly disturbed spells. But I do agree the Ops runs shouldn’t be taken as gospel further out, that said when it’s mixed in within a huge degree of scatter and painting a reasonable stable picture it should certainly hold more weighting. 

[mb018538]

On 16/08/2021 at 18:04, summer blizzard said:

GFS has moved towards retreogression vs the GEM model building east.

Tropical forcing vs La Niña….one wants to build, one wants to retrogress. Conflicting signals, chaotic output!

[Frosty.]

The Gem has been sensational today, both the 0z I posted earlier and now the 12z!...doesn’t mean it’s right of course but it sure is pretty!  

[Methuselah]

8 minutes ago, Alderc said:

I don’t understand why so many people post charts say they look good without looking at the underlying details only for them to be crap. 

Thankfully, I've tended to ignore most your divinations, Chris; had I not done so, I'd have looked a prize lemon -- dressed in my oilskin plus goloshes combination! That being as it may, the GS 12Z operational run doesn't look all that bad to me. 

    

    

    

Retrogression? 

[Guest]

And for something completely different, snowfall anomaly forecast for the coming winter! Good news if you ask me! 

[Methuselah]

2 minutes ago, Alderc said:

And for something completely different, snowfall anomaly forecast for the coming winter! Good news if you ask me! 

Or . . . utterly meaningless? 

[Frosty.]

Meanwhile, back at the ranch...the GEFS 12z mean for next week looks jolly spiffing doesn’t it old chap?!  

[Methuselah]

1 minute ago, jon snow said:

Meanwhile, back at the ranch...the GEFS 12z mean for next week looks jolly spiffing doesn’t it old chap?!  

Top hole!