Model Output Discussion 18z 28/07/13

[mushymanrob]

 

I see that mushy and john are both pointing to the anomoly charts to predict more in the way of upper trough trend than an upper ridge one from those signals, and their reasoning makes plenty of sense, but all the same we may end up with more of a NW/SE divide (or a N/S one) in reality, than looks likely just now.

 

 

 

hey i take no credit...it was john who has studied these charts and john who has done the hard work. i am finding that his conclusions are pretty accurate for the period they apply for. hence if the ops are showing a azh ridge, but the anomalies dont for the same time period, my monies are on the anomaly being correct. im posting them quite often, but am not trying to muscle in and take credit for them... im following what john has been saying for quite a while now, if we all take note of these charts then maybe there wont be so much disappointment when heat or cold spells fail to emerge.

 

appreciate the comments guys.. ive had abit of stick recently for my 'negetive' comments, which unfortunately appear to be coming into fruition...

 

tbh im pretty melancholy that theres no more heat....

[William of Walworth]

Points taken. I'm not very good on reading/understanding anomoly charts so I tend to rely on interpetation of them from others -- as you say john knows his onions on them very well.

 

Still, my point from before remains, lets check further operational and ensemble runs over coming days and with caution, because we just don't know yet whether or not the suggested Atlantic fireup is being pushed too early or too much (or too universally perhaps, in UK-geographic terms -- my money stays on a zonal divide of some sort).

Edited August 5, 2013 by William of Walworth

[William of Walworth]

Well this thread's gone worrryingly quiet. I haven't got time right now to check latest output properly myself, apologies. But do I conclude that no news is bad news (in summer terms). Or just that our regular model watchers and readers are just busy for now as well, and waiting for more evidence and pointers?

Edited August 5, 2013 by William of Walworth

[draztik]

I actually don't think the output is all that bad. If you live in the South, it looks pretty decent. It does appear the NW will bear the brunt of the unsettled conditions. I think people were spoiled in July, and so this weather pattern that the models appear to endorse seems almost 'boring' in comparison.

[Summer Sun]

Well this thread's gone worrryingly quiet. I haven't got time right now to check latest output properly myself, apologies. But do I conclude that no news is bad news (in summer terms). Or just that our regular model watchers and readers are just busy for now as well, and waiting for more evidence and pointers?

 

I would say its looking average for many some sunshine, some rain, some cloud and windy at times with the best weather at times reserved for the south and SE compared to previous August's which up here have been cool, wet and windy average would be a lot better

[Methuselah]

Well this thread's gone worrryingly quiet. 

Football season started? Ashes Series well underway? Transfer Window well and truly open? All-time heat records, gone? No chance of snow? There is a multitude of reasons, William...

[Frosty.]

I don't think there has been much change in the Ecm 00z ensemble mean, the south still gets the ridging from the azores/atlantic anticyclone for friday and the weekend and looking into next week, the further south you are, the less rain and more dry and sunny weather you will get with decent temperatures, even today is 24c in cambridge and 23.1c across heathrow and those type of temperatures are set to continue all week and probably rise a few degrees later in the week, 25-26c close to 80F in the south, so, for central and southern parts of the uk, the weather looks warmish or warm with a lot of fine and fairly sunny weather and a few showers dotted around, tomorrow looks mainly dry, probably wednesday brings the greatest chance of heavy, slow moving showers and then back to a few light showers on thursday, then sunnier and warmer across the south just in time for the weekend with mid 20's celsius, progressively less warm and less settled as you push much further north, scotland & n.ireland having a more changeable pattern throughout with temperatures closer to average but fine and pleasantly warm from time to time, it's not bad at all, it's average and average is a lot better than that cool washout summer last year.

[William of Walworth]

As Frosty says ....

 

it's not bad at all, it's average and average is a lot better than that cool washout summer last year.

 

 

Quite right -- seen a whole lot of worse!

 

I guess I was guilty of combining shortage of checking time  with panic, earlier on.

Edited August 5, 2013 by William of Walworth

[Milhouse]

The GEFS mean suggesting an arrival of something cooler from the northwest is likely early next week before high pressure from the azores brings a warmer flow in from the west.

 

[J10]

The ECM looking very agreeable with a NW flow setting in for the middle of this week and into next week, the Azores is also set to return so some dry (much needed after recent deluges) and sunnyish weather especially for Southern and South Western areas.

 

Quaite unusual to see this sort of pattern in recent years in August, this is more of an early summer setup.

[Frosty.]

A pretty fair Ecm 12z run tonight with the azores/atlantic anticyclone ridging across the south of the uk from friday and lasting throughout the weekend with some very pleasant fine and sunny weather for a while and temperatures into the low to mid 20's celsius, although the chart for friday shows 1020mb pressure for the south, bear in mind that this fax chart from earlier shows an occluded front pushing east across the uk on friday with a band of cloud and mostly light rain but pressure looks like rising more strongly once the front has cleared through and setting up a nice few days for southern britain, the north of the uk looks more generally changeable but with some decent weather too, the ecm shows the atlantic ridge briefly being pushed further southwest as a trough slides southeast from iceland and shears across northeast scotland and then away into scandinavia, once the trough has cleared east, pressure rises across the south again although another low moving in off the atlantic early next week may flatten the ridge somewhat but the weather across the south would at least be rather better than further north, the pattern looks flatter overall so the temperatures across the south would never be worse than average (low 20's celsius) and would actually be nearer mid 20's for a while, for the north, anything from mid to high teens celsius to low 20's c looks more realistic but once again, following the decent ecm 00z ens mean this morning and the latest gefs 12z mean, things are looking generally better than the models were showing recently for the mid august period, high pressure looks like having more influence at least for the southern half of the uk during the next 10 days or so but scotland & n.ireland have it the other way round, more low pressure than high..yes it's mostly average but it's still very acceptable august weather compared to recent years.

[Methuselah]

^^ Just why the Scottish summer holidays end in mid-August?

[ANYWEATHER]

The Azores high is delivering fairly cool, changeable/unsettled in the near future at the T+96 period. Before then some reasonable temps to tap into although some heavy showers to boot!  

[East_England_Stormchaser91]

One thing I wont mind about that possible low coming down from the NW, is that it could bring a PM showery Northwesterly, which have often brought some of the most potent hailstorms and thunderstorms over the years here. With the cold temperatures aloft and the ground still warm from the hot July we had, surely it could deliver something pretty exciting. 

[Tamara]

One thing I wont mind about that possible low coming down from the NW, is that it could bring a PM showery Northwesterly, which have often brought some of the most potent hailstorms and thunderstorms over the years here. With the cold temperatures aloft and the ground still warm from the hot July we had, surely it could deliver something pretty exciting. 

I think that at least as of this evening, the models maybe have reigned back just a fraction on the amplified pattern that has been suggested this morning. The general theme stays the same with more of a North Atlantic influence in the further outlook than we have seen, and with lower temperatues by comparison. But the nationwide split in conditions is maybe more emphasised once again this evening on the basis that the cold uppers and instability you are thinking about at this distance maybe are not going to get that far south with the jetstream not buckling enough to dig the trough far enough south for this to happen  However, as already stated today, this is uncertain a week and more away and time as always will tell

[Jonathan Lang]

Getting a little confused. When you guys are saying northern areas will bear the brunt of unsettled weather and southern parts fair better, where do central parts of the uk fit in? Namely the yorkshire/lancashire band. Is this considered central england or does that refer to the midlands?

[Frosty.]

Getting a little confused. When you guys are saying northern areas will bear the brunt of unsettled weather and southern parts fair better, where do central parts of the uk fit in? Namely the yorkshire/lancashire band. Is this considered central england or does that refer to the midlands?

When I refer to northern britain I mean n.ireland, scotland and cumbria across to northumberland and the south from lancashire across to yorkshire and all points south.

[William of Walworth]

Those snapshot 12z charts that ANYWEATHER posted contrast quite sharply with the ones that Frosty posted. It's all too early in the day  (and again, I'm short of time) but how do people reconcile the different messages?

Edited August 6, 2013 by William of Walworth

[mushymanrob]

Getting a little confused. When you guys are saying northern areas will bear the brunt of unsettled weather and southern parts fair better, where do central parts of the uk fit in? Namely the yorkshire/lancashire band. Is this considered central england or does that refer to the midlands?

 

theres no set boundary... it can vary to who gets what depending upon the exact track of the jet/fronts/lows and the exact position and strength of the high to the south. here in derby i can be either when its 'warm and sunny in the south, wet and windy in the north'... although usually somewhere inbetween.

 

 

the gradual slide from the heat the other week is ongoing, as temps slowly come down, and after this rather benign spell by the end of the week the atlantic is still set to return us to a mobile, zonal regime. theres still no tangible sign of a lasting settled spell and certainly no heat. if we can dodge the rain/showers and catch some sunshine itll be pleasant enough, but with an upper air trough expected close to our north, and a ridge to our west linking the azh with a greenland high, theres some very cool air to tap into.

 

'writing off summer' might be emotive, some would say daft and with little basis in science... but really? the pattern we are in is gradually moving away from anything settled, and this mornings models (plus the anomalies) suggest we havnt 'bottomed out' yet in this decline. its still getting further away from anything 'hot'. whilst its possible that something might evolve out of the blue, for my mind id suggest thats highly unlikely, and the rest of the month/summer will be atlantic dominated with no more heat (25c+ ) (this is a general statement, and southern/seastern areas might pull an odd day here and there out the hat).

 

there is of course time for something warm, even hot, in early autumn (september), but that depends upon how long we will be in a zonal pattern, and when that changes what follows on.

Edited August 6, 2013 by Osbourne One-Nil
You don't need to keep point scoring - you're doing it in every post!

[Captain Shortwave]

There is quite a difference in the models when you get to next Monday

GFS has the low north of the UK

So does the ensemble

 

UKMO has the low centred over Scotland and would be much cooler and unsettled.

Edited August 6, 2013 by Captain shortwave

[mushymanrob]

Those snapshot 12z charts that ANYWEATHER posted contrast quite sharply with the ones that Frosty posted. It's all too early in the day  (and again, I'm short of time) but how do people reconcile the different messages?

 

by checking what the anomaly charts suggest... they are the best indicator as to the general synoptic pattern, from those you can then get an idea of which chart/run is most plausible.

[mushymanrob]

There is quite a difference in the models when you get to next Monday

GFS has the low north of the UK

So does the ensemble

 

UKMO has the low centred over Scotland and would be much cooler and unsettled.

 

and the anomaly chart for this period would suggest the ukmo is closer to the mark

 

a trough situated just to our north (east of north) opening the doors to some cool northwesterlies.

[Captain Shortwave]

and the anomaly chart for this period would suggest the ukmo is closer to the mark

610day.03.gif

 

a trough situated just to our north (east of north) opening the doors to some cool northwesterlies.

That's all well and good but in a few hours time the anomaly charts might be completely different, especially if the GFS/ECM agree which they now do

Trough north of Scotland instead of through Scotland

True there is no heatwave but surface conditions don't look too bad. Average to warm would be describe it. 

Edited August 6, 2013 by Captain shortwave

[mushymanrob]

That's all well and good but in a few hours time the anomaly charts might be completely different, especially if the GFS/ECM agree which they now do

Trough north of Scotland instead of through Scotland

True there is no heatwave but surface conditions don't look too bad. Average to warm would be describe it. 

 

true, but unlike the ops the anoms dont chop and change as much...

 

i hope they do change for the better, but until they do im not getting any vague hopes up.

[Frosty.]

Those snapshot 12z charts that ANYWEATHER posted contrast quite sharply with the ones that Frosty posted. It's all too early in the day  (and again, I'm short of time) but how do people reconcile the different messages?

glass half empty and half full I think, I try and look for the good in the bad and some look for the worst they can find.