Model Output Discussion 18z 28/07/13

[Methuselah]

Considering that not one of the models' 'solutions' is likely to materialize, I'd agree about using caution...

[Frosty.]

Considering that not one of the models' 'solutions' is likely to materialize, I'd agree about using caution...

Agreed Pete but the overall synoptics next week look very slack and it will warm up again after the cool blip and sunshine levels should also increase but there will probably be a continuing risk of scattered heavy and thundery showers due to a residue of instability but with long sunny periods between any showers it would be feeling summery.

Edited September 4, 2013 by Frosty.

[Methuselah]

Agreed Pete but the overall synoptics next week look very slack and it will warm up again after the cool blip and sunshine levels should also increase but there will probably be a continuing risk of scattered heavy and thundery showers but with long sunny periods between and feeling warm again.

Indeed, Frosty...It does look like staying on the warm side of things, next week...

[Captain Shortwave]

Even by mid month the 06GFS keeps a fairly noticable 500mb height anom to the S, so whilst it's perhaps tempting to get suckered into ECM's much drier, more settled picture caution is advised. 

 

 

I think the question is, is that low likely to stay stuck to the south of us for that long? Logic states it should move back northwards in time.

Given how the amount of digging south the trough has done has been reduced towards T0, For example we moved towards the UKMO solution yesterday for example which did just this. 

The interesting thing about the ECM is that it goes even further than the UKMO did with reducing this effect to the point where the low never actually becomes cut off, this leads to the trough ejecting back northwards at quite a swift pace. So by Tuesday the low is now over northern Scandinavia as opposed to stuck over the UK.

This afternoons runs will be interesting, will the ECM trend from this morning continue, will other models start to side with it. 

Urgh I think I need to change my avatar at this point.... KARL!!! 

Edited September 4, 2013 by Captain shortwave

[Frosty.]

You would be forgiven for thinking we had turned the clock back to mid July, these initial charts are superb for the south & east, tomorrow looks even hotter in the southeast with 29-30 celsius and a lot of sunshine but there is also a risk of an isolated heavy shower with thunder but 99% of the hot area would remain sunny, gradually worse the further you move northwest from the hot zone but by friday and the weekend we will all be in it together with a real dogs dinner of widespread heavy downpours and much cooler although the 6z shows temps recovering by sunday for the south and east with a window of fine and sunnier weather, back into the low 20's celsius, through next week the temperatures try to recover but there is some unsettled weather indicated which would put a dent in the max temps on certain days but there would also be some fine and sunnier days with temps close to 22 celsius, at least across the southern half of the uk, rather cooler further north but pleasant at times, not a settled week but not a washout either..something for everyones taste I would say, further on it's a north-south split, the longest fine and warm spells for the south, cooler and more unsettled for the northern third of the uk later in FI.

Edited September 4, 2013 by Frosty.

[shedhead]

I think the question is, is that low likely to stay stuck to the south of us for that long? Logic states it should move back northwards in time.

Given how the amount of digging south the trough has done has been reduced towards T0, For example we moved towards the UKMO solution yesterday for example which did just this. 

The interesting thing about the ECM is that it goes even further than the UKMO did with reducing this effect to the point where the low never actually becomes cut off, this leads to the trough ejecting back northwards at quite a swift pace. So by Tuesday the low is now over northern Scandinavia as opposed to stuck over the UK.

This afternoons runs will be interesting, will the ECM trend from this morning continue, will other models start to side with it. 

Urgh I think I need to change my avatar at this point.... KARL!!! 

Agreed CS, hence why I advised caution on assuming either evolution will prove correct, in fact history suggests we will probably end up half way between the current two extremes. As you say the 12 runs will be interesting, but I think at this stage the odds probably favour a drift towards GFS from ECM, not visa versa.

Edited September 4, 2013 by shedhead

[draztik]

The latest output from NAVGEM keeps LP parked over the UK into Tuesday of next week.. This may be a lower tier model, but still no movement towards that of the ecm at this point...

[Frosty.]

The GEFS 06z control run gradually turns into a beauty of a run with high pressure slowly but surely taking control of the control and only losing it by september 20th, around the autumn equinox, if the fine and warm weather does come back with a vengeance, I won't care if the jet fires up later in september because we would have enjoyed a very nice bonus spell of summery weather by then, there are lots of positives to take from the output so far today, the ecm 00z looks sunny and warm for much of next week and the latest ens mean charts show temps rising again next week after the cool and unsettled blip.

Edited September 4, 2013 by Frosty.

[Polar Maritime]

Could not stop myself posting the far distant chart from the GFS, showing a nice cold PM N/W flow. We would see the first snow over the Scottish mountains with that chart.

 

Edited September 4, 2013 by Polar Maritime

[Frosty.]

The GEFS 06z mean turns out equal to the control run with growing anticyclonic influence as time goes on and actually ends better, especially for the southern half of the uk, as for next week, the mean shows the resident cool shallow trough filling and losing it's identity, it gets squeezed from both sides by high pressure in the atlantic and across southern scandinavia, the uk then lies within a slack pressure field with a mix of sunny periods and scattered heavy showers and temperatures bouncing back into the low to mid 20's celsius although low 20's c is a safer bet at this stage which is not to be sniffed at as we head towards mid september, if the anticyclone does build in, I see no reason why temps should not head more generally into the mid 20's celsius but with light winds and under clear skies overnight, the risk of fog increases, as we have already seen this morning.

[Captain Shortwave]

GFS might be moving towards the ECM solution on this run

 

Previous run

Good couple of hundred miles further north the low

 

UKMO doing something similar

Edited September 4, 2013 by Captain shortwave

[No Balls Like Snow Balls]

I think the GFS is moving to the ECM solution on this run

 

Previous run

Good couple of hundred miles further north the low is now and looking similar to this mornings ECM run.

 

 

It certainly looks that way. UKMO going same way at T96 by looks of it to?

Edited September 4, 2013 by No balls like Snow Balls

[Summer Sun]

Good news folks GFS is moving in the direction of ECM

 

 

Edited September 4, 2013 by Summer Sun

[Captain Shortwave]

Just for laughs

GFS day 5

 

06Z

 

Again the models have failed epically in these split energy situations. Heaven forbid we get situations like this during the winter. 

Edited September 4, 2013 by Captain shortwave

[No Balls Like Snow Balls]

Good news folks GFS is moving in the direction of ECM

 

 

 

Its only good news if you like boring weather. You should remember it's not good news for everyone and try to be non-biased

[Summer Sun]

Its only good news if you like boring weather. You should remember it's not good news for everyone and try to be non-biased

 

Just wait till winter the only posts in here will be biased to cold and snow!

 

UKMO moving in the right direction as well

 

 

GFS continues its move to ECM

 

 

Warmer air pushing back into the SW

 

 

ECM at t144 to compare (00z run)

 

 

It looks like ECM was on the right track after all with UKMO and GFS coming inline now

 

Edited September 4, 2013 by Summer Sun

[Summer Sun]

Just for laughs

GFS day 5

 

06Z

 

Again the models have failed epically in these split energy situations. Heaven forbid we get situations like this during the winter. 

 

Seems like ECM 00z was on the money as it picked up this trend first this morning - http://www.null/ds/ecm.htm (Tuesday onwards)

[draztik]

Like has been the case this summer, the Azores high doesn't care that we are in Sept, and wants to stay around for a while yet. As for the GFS, are we going to see a major shift in its ensembles, as they had been consistent in showing LP out to t180, now the ops are showing the low shifting by t96 Northwards. Makes you not even want to look at its output.

[Summer Sun]

Low pressure remains anchored across Greenland which lets the Azores high build back over the UK after a blip again this weekend with Friday looking like a washout

 

 

Although lower than this week temperatures remain very respectable for the time of year

 

Edited September 4, 2013 by Summer Sun

[Summer Sun]

The further through GFS we go the more high pressure dominates

 

 

UKMO ends with the Azores pushing back in

 

 

Edited September 4, 2013 by Summer Sun

[ANYWEATHER]

The further through GFS we go the more high pressure dominates

 

 

Yes again the models are clueless, past t+96  

[draztik]

Yes again the models are clueless, past t+96  

 

I know, its like a pick n mix... in a 6hr period, you go away thinking you'll need your waterproofs, then come back and see you'll need your shorts and t-shirt. I think what you say is right, I expect changes for the next few days in trying to nail down next weeks output.

[Captain Shortwave]

GEM has also gone the same way

 

[ANYWEATHER]

I know, its like a pick n mix... in a 6hr period, you go away thinking you'll need your waterproofs, then come back and see you'll need your shorts and t-shirt. I think what you say is right, I expect changes for the next few days in trying to nail down next weeks output.

To be honest, the models are really struggling still with exactly where the weekends low is gonna be! I expect the next gfs run to be different again to its 12z run! And, as for the ecm, I would be very surprised to if its whistling the same tune on this evening 12z run compared to its 00z morning run!  

[Summer Sun]

GEM is moving to ECM and GFS as well