Model Output Discussion 18z 28/07/13

[Newberryone]

As with the Gfs 00z op and GEFS 00z control run, the GEFS 00z mean shows high pressure winning out from mid month onwards with increasingly benign, settled and warm weather with long sunny spells and light winds with temperatures into the low 20's celsius bringing a nationwide taste of summer but since it's autumn, overnight it would turn rather chilly with fog forming. It's not a smooth transition to settled weather, the azores/atlantic high has to roll with the punches for a while as unsettled weather sweeps across more northern parts of the uk but when the high gets it's chance, it takes it big time, let's hope this trend continues and we have a golden spell of weather through the second half of the month and possibly into early october.

While I share your optimism Karl regarding the ever promising outlook for September in general I can't help but fear your liking of the Azores high may come back to haunt you during the upcoming winter season. As you well know it's basically taken up what seems like permanent residence these past few months. However, should this become a dominant feature Nov-Feb inclusive, it will ultimately scupper any hopes you may have of a mighty big winter freeze.

[Frosty.]

While I share your optimism Karl regarding the ever promising outlook for September in general I can't help but fear your liking of the Azores high may come back to haunt you during the upcoming winter season. As you well know it's basically taken up what seems like permanent residence these past few months. However, should this become a dominant feature Nov-Feb inclusive, it will ultimately scupper any hopes you may have of a mighty big winter freeze.

I see what you mean but i'm just taking things as they come, my optimism is strengthened by what the met office said yesterday, as they were saying pretty much what the GEFS 00z mean is showing this morning, a trend towards a settled and warm outlook, there is substance to it, I don't think a warm settled early autumn will have any bearing on the upcoming winter, I heard on the grapevine there is a good chance of a cold blast in november with a risk of snow later.

Edited September 7, 2013 by Frosty.

[Frosty.]

Another promising Gfs 06z to go with the 00z, the second half of september is looking generally anticyclonic with lots of pleasantly warm sunshine, there is continuing evidence of a large scandi high forming and becoming a major blocking feature for the uk to stop atlantic depressions in their tracks, the charts definately look more summery than autumnal and the week ahead does slowly improve as the residue of instability eventually subsides with a weak pressure rise bringing a window of sunnier and warmer weather after the showery start to next week, the PFJ looks like remaining to the northwest of the uk, sometimes way to the northwest during the next month or so and steering the worst of the autumn weather across greenland & iceland

Edited September 7, 2013 by Frosty.

[syed2878]

i'm not supprised gibby doesn't want to post in this thread and i don't blame him. Too many forecasters on here nitpick his summeries because he doesn't say what they want to heare. Now the moddels i hope they start showing autumnal weather soon.

[Frosty.]

The latest met office update is again very encouraging looking further ahead with a trend towards a more generally settled and warm outlook with long sunny spells, light winds and overnight fog patches which is pretty much what the models are showing in FI. In the short term, tomorrow looks drier for many areas with sunny spells but with a scattering of sharp showers with a risk of thunder and feeling pleasant out of the breeze, monday brings sunny periods and scattered showers, tuesday brings a risk of rain for the east of the uk with sunshine and scattered showers further west, wednesday is mainly dry with sunny spells and just isolated showers, thursday also looks fine in the south of the uk with sunny periods and feeling a little warmer again, nudging into the low 20's celsius, becoming more unsettled across the northwest corner of the uk during thursday and eventually this spreads southeast to all areas but only affects the south for a day or two at most before settling down again with warm sunny spells and light winds with overnight fog, then high pressure looks like building in across most of the uk for the second half of the month...very nice indeed...BANK 

Edited September 7, 2013 by Frosty.

[Summer Sun]

I'm not surprised Gibby doesn't want to post in this thread and i don't blame him. Too many forecasters on here nitpick his summaries because he doesn't say what they want to hear. Now the models i hope they start showing autumnal weather soon.

 

That's the problem in the model thread during winter if the charts are not showing cold weather you get shot by the coldies for posting anything mild some of them just can't accept that milder spells during a UK winter a quite common after all we are not in Scandinavia where its cold every winter just imagine what it would have been like on weather forums in the 90's and 00's when mild winters were very frequent in the UK

Edited September 7, 2013 by Summer Sun

[Summer Sun]

06z ensembles maintain the steady rise in uppers from around the 13th (Friday the 13th of all days the final one of 2013 and the final one till February 2015)

 

Rainfall remains low as well

 

[Frosty.]

 i hope they start showing autumnal weather soon.

Sometime towards mid october.

[No Balls Like Snow Balls]

So the consensus from all the models is for high pressure to re-establish next week. How ever all the online forecasts i have seen for next week point to it being very cloudy from midweek onwards with daytime temps struggling to reach average. Maybe the bbc and met office forecasts will turn out to be wrong but that is what they currently show. Therefore those expecting it to feel summer like next week maybe left bitterly disappointed.

[DR(S)NO]

That's the problem in the model thread during winter if the charts are not showing cold weather you get shot by the coldies for posting anything mild some of them just can't accept that milder spells during a UK winter a quite common after all we are not in Scandinavia where its cold every winter just imagine what it would have been like on weather forums in the 90's and 00's when mild winters were very frequent in the UK

Tbh Gavin,i think its a problem all year round........if only the British seasons were more clear cut and we always got the weather that suited the season......but then we would have little to argue over!

[Summer Sun]

GFS 12z is underway high pressure moves in before the low to the north of the UK pushes it south

 

 

UKMO out to t72 also has high pressure moving in the further west you are the better it would be the SE would be prone to cloud and rain until that LP system cleared away

 

 

t96 on UKMO shifts the low away becoming dry for all

 

 

Looking at GFS the high could well rebuild quite quickly from the west

 

 

High pressure does indeed build back in

 

Edited September 7, 2013 by Summer Sun

[Summer Sun]

UKMO ends with the high staying over the UK

 

 

High pressure returns in time for next weekend according to GFS

 

Edited September 7, 2013 by Summer Sun

[Frosty.]

You can clearly see one of the reasons why the met office are going for a settled and warm further outlook when you look through the GEFS mean charts today, the 00z showed it and now the 6z mean, becoming more anticyclonic, benign, warm and sunny with light winds and overnight fog with the south of the uk being best placed for the most good weather in the next 2-4 weeks although the north should also join in the settled spell as time goes on.

[Frosty.]

Gfs 12z again showing a warm and anticyclonic further outlook, the support for a fine and settled second half to september is continuing to grow and grow

[johnholmes]

re this from frosty, the end of his post

south of the uk being best placed for the most good weather in the next 2-4 weeks although the north should also join in the settled spell as time goes on.

 

I suspect this is a touch of hopecasting as nothing I can see suggests this is more than about 50% likely and even less than that % for the north. Read the Met O 6-15 and 16-30 day updates CAREFULLY, neither do they suggest that and the anomaly charts do not support the inference of 2-4 weeks settled weather, 2 weeks perhaps for some southern districts is the most one could expect looking at any model outputs from whatever source, in my estimation at any rate.

I suspect that the very large temperature differences being suggested on the GFS model at least (at 850mb) will generate quite large depressions running in the usual area to the south of Iceland by early October if not before, bring unsettled spells to the NW'ern half and even at times to the rest of the UK.

 

As well as that proviso at this time of the year all it needs is for a major hurricane to develop and recurve out into the Atlantic and any model or any forecaster is going to be wrong. Thanks to the enormous amounts of energy they release NONE of the models are much good at long time scales in picking these up let alone getting their tracks correct if they do get into the Atlantic.

 

sorry if this sounds a sour puss type post but it is an honest  opinion with a lot of experience behind it.

As ever I may be wrong and have yet more egg on my face!

Edited September 7, 2013 by johnholmes

[Frosty.]

re this from frosty, the end of his post

south of the uk being best placed for the most good weather in the next 2-4 weeks although the north should also join in the settled spell as time goes on.

 

I suspect this is a touch of hopecasting as nothing I can see suggests this is more than about 50% likely and even less than that % for the north. Read the Met O 6-15 and 16-30 day updates CAREFULLY, neither do they suggest that and the anomaly charts do not support the inference of 2-4 weeks settled weather, 2 weeks perhaps for some southern districts is the most one could expect looking at any model outputs from whatever source, in my estimation at any rate.

I suspect that the very large temperature differences being suggested on the GFS model at least (at 850mb) will generate quite large depressions running in the usual area to the south of Iceland by early October if not before, bring unsettled spells to the NW'ern half and even at times to the rest of the UK.

 

As well as that proviso at this time of the year all it needs is for a major hurricane to develop and recurve out into the Atlantic and any model or any forecaster is going to be wrong. Thanks to the enormous amounts of energy they release NONE of the models are much good at long time scales in picking these up let alone getting their tracks correct if they do get into the Atlantic.

 

sorry if this sounds a sour puss type post but it is an honest  opinion with a lot of experience behind it.

As ever I may be wrong and have yet more egg on my face!

Fair points John, I know nothing compared to you, I am only going on the model output i'm looking at and the promising meto 6-15 day & 16-30 days which becomes better and better as time goes on, their further outlooks are about as good as we are ever going to get at this time of year and boy have we had it good for the last 4 months already with records being smashed left, right and centre.

Edited September 7, 2013 by Frosty.

[Summer Sun]

What a difference a year makes last September it was a continuation of the floods this year its a continuation of the settled quiet weather a much better September all round this year

 

Even at the very end of its run GFS (inline with the met office long term update) maintains the mostly settled spell with low pressure systems continuing to head into Greenland

 

[No Balls Like Snow Balls]

Fair points John, I know nothing compared to you, I am only going on the model output i'm looking at and the promising meto 6-15 day & 16-30 days which becomes better and better as time goes on, their further outlooks are about as good as we are ever going to get at this time of year and boy have we had it good for the last 4 months already with records being smashed left, right and centre.

What records have been broken in the last 4 months? Genuine question cos i don't recall any but to be fair i have a bad memory

[Frosty.]

What records have been broken in the last 4 months? Genuine question cos i don't recall any but to be fair i have a bad memory

Erm let me see...driest summer in england since 1995/96....hottest July since 2006, hottest august day since 2003, hottest september day for 7 years..warmest, driest and sunniest summer since 2006.

[Summer Sun]

ECM maintains the pressure rise this evening best in the west at first but quickly improving in the east

 

[Scorcher]

Erm let me see...driest summer in england since 1995/96....hottest July since 2006, hottest august day since 2003, hottest september day for 7 years..warmest, driest and sunniest summer since 2006.

 

Some areas have actually had their best summer since 1995 too.

[Captain Shortwave]

ECM does not have the trough digging south on this run

[bluearmy]

JH right as ever but NEAFS builds an impressive high anomoly towards the end of week 2 which would no doubt see us through week 3 if it verified.  the caveat being that this 'solid' high anomoly is struggling to get much closer than day 14 at the moment with a more gentle one being on offer below this timescale.

[Summer Sun]

ECM maintains the mostly settled theme tonight as ever there are one or two exceptions the biggest is at t192 for Scotland as that low clear at t216 the east could become cloudy with a risk of some showers

 

 

 

The continuing theme tonight is a blocked Atlantic keeping things quite  

[Summer Sun]

ECM ends with high pressure in charge once more

 

 

With it comes warmer air

 

 

With low pressure staying anchored over Greenland I can't see any end to this sort of pattern for a long time yet especially with the Atlantic dead there is nothing to shift the Azores high

 

Our extended period of fairly quiet weather looks set to continue into the second of of September this evening