Model Output Discussion 18z 28/07/13

[Frosty.]

The GFS 06z operational run shows a stunning recovery after such a cool, windy and unsettled start to next week, especially across the far north of the uk where it will be stormy for a time with even a risk of hill and mountain sleet or snow, from such a low starting point, the only way is up and high pressure  builds in later next week and assumes full control, gradually drifting east to become centred to the east or southeast of the uk with increasing warmth and lots of sunshine with temperatures sailing into the low to mid 20's celsius, it would eventually bring a perfect spell of weather for most of the uk, this run shows the full potential of what the ensemble mean charts, especially the GEFS, have been showing for many days now.

Edited September 11, 2013 by Frosty.

[No Balls Like Snow Balls]

GF06Z ensembles show the latter half of the run was a near warm outlier. So would suggest that HP will not end up South of the UK as per shown on op run.

Latest 500mb anomolys suggest core of any HP will be stuck out West of the UK rather than South of the UK, keeping us in a cooler West / Nwerly flow. Would be very very very surprised if 06z op run verified with HP to South.

 

 

 

 

 

[Gavin Hannah]

Just watched the Beeb weather forecast... Potentially the first major Autumn storm this sunday. 

 

 

 

It looked a lot more dramatic on TV lol.

Edited September 11, 2013 by IBringTheHammer

[TwisterGirl81]

Does anyone else wish the low pressure was a little further south on Sunday, I am so ready for a storm but I guess Scotland will almost always be the place that gets them.

[Frosty.]

Does anyone else wish the low pressure was a little further south on Sunday, I am so ready for a storm but I guess Scotland will almost always be the place that gets them.

Yes and i'm sure most people in scotland are not looking forward to 70-80 mph winds ripping roofs off and uprooting trees still in full leaf, not to mention potential flooding due to torrential rain.

Edited September 11, 2013 by Frosty.

[Gavin Hannah]

Yes and i'm sure most people in scotland are not looking forward to 70-80 mph winds ripping roofs off and uprooting trees still in full leaf, not to mention potential flooding due to torrential rain.

 

Scotland never floods   We bottle it and sell it lol...

Edited September 11, 2013 by IBringTheHammer

[tempestwatch]

Does anyone else wish the low pressure was a little further south on Sunday, I am so ready for a storm but I guess Scotland will almost always be the place that gets them.

You can have it Could be some damage in the far north, trees are still full of leaves!

[TwisterGirl81]

Yes and i'm sure most people in scotland are not looking forward to 70-80 mph winds ripping roofs off and uprooting trees still in full leaf, not to mention potential flooding due to torrential rain.

 

 

I'm sure with the amount of winter storms you get the roofs are reinforced and the tree roots are probably more resistant to wind.

 

Weather is going to happen whether we like it or not and I LOVE storms but not people getting hurt but that's the thing about mother nature, you can't predict or fight it so just embrace the changes!

Edited September 11, 2013 by TwisterGirl81

[Captain Shortwave]

Does anyone else wish the low pressure was a little further south on Sunday, I am so ready for a storm but I guess Scotland will almost always be the place that gets them.

Bring it on, anything can't be worse than yesterday 

[Frosty.]

I'm sure with the amount of winter storms you get the roofs are reinforced and the tree roots are probably more resistant to wind.

 

Weather is going to happen whether we like it or not and I LOVE storms but not people getting hurt but that's the thing about mother nature, you can't predict or fight it so just embrace the changes!

unfortunately, autumn storms like the one being modelled for sun/mon will hurt or kill people and cause £millions of damage, stopping ferry services, disrupting transport and damaging peoples homes and businesses, I would rather embrace the warm and anticyclonic weather later in the month thanks.

[TwisterGirl81]

unfortunately, autumn storms like the one being modelled for sun/mon will hurt or kill people and cause £millions of damage, stopping ferry services, disrupting transport and damaging peoples homes and businesses, I would rather embrace the warm and anticyclonic weather later in the month thanks.

 

Well unfortunately you realise that we need rain and wind as well as nice weather for all sorts of things like our resevoirs, crops and wind farms for renewable energy....I guess the north didn't get as nice a summer as the south so I can understand you wanting nice weather.

 

I tend to stay inside when its very bad weather

[johnholmes]

To follow the GFS view of how/when/where this low will devlop and move go here

http://www.netweather.tv/index.cgi?action=nwdc;sess=fe669b921dfa10d87c74b08a0b5772d6

 

input in one box the 500-slp chart and in the other the jetstream, and see how the current output may vary from the previous output, a useful check on how consistent the model is being. 

 

one can see how the low develops just ahead of the jetstream (called its left exit) and continues to deepen as the jet strengthens. Note, for those wondering if the low might not be further south) it cannot come south unless the jet is being predicted too far north=unlikely, as all 3 models show a similar area of formation (behind the original low) and track although the depth has some variation between the 3.

Edited September 11, 2013 by johnholmes

[Frosty.]

Well unfortunately you realise that we need rain and wind as well as nice weather for all sorts of things like our resevoirs, crops and wind farms for renewable energy....I guess the north didn't get as nice a summer as the south so I can understand you wanting nice weather.

 

I tend to stay inside when its very bad weather

Yep I agree with you there.

[Nick F]

To follow the GFS view of how/when/where this low will devlop and move go here

http://www.netweather.tv/index.cgi?action=nwdc;sess=fe669b921dfa10d87c74b08a0b5772d6

 

input in one box the 500-slp chart and in the other the jetstream, and see how the current output may vary from the previous output, a useful check on how consistent the model is being. 

 

one can see how the low develops just ahead of the jetstream (called its left exit) and continues to deepen as the jet strengthens. Note, for those wondering if the low might not be further south) it cannot come south unless the jet is being predicted too far north=unlikely, as all 3 models show a similar area of formation (behind the original low) and track although the depth has some variation between the 3.

 

Most of the 00z EPS going for centre of next Monday's deep low to be no further south than Scotland.

 

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!132!pop!od!enfo!enplot!2013091100!!/

 

Nonetheless, a rather disturbed pattern evolving from the weekend onwards, as a strong (180mph+) jet comes roaring across the Atlantic, fuelled by a rapid cooling of the air over NE Canada and Greenland interacting with tropical air being drawn north over the NW Atlantic by TS Gabrielle, who's remnants look to be near New Foundland by Saturday morning.

 

Can't help but feel that the 500mb ridge block over Nern Russia/Siberia and troughing further west over Scandi/eastern Europe will keep as in this cool and unsettled flow for the foreseeable aswell.

Edited September 11, 2013 by Nick F

[Summer Sun]

Looking at the wind speeds its the northern Isles of Scotland which are going to take the brunt the further south you are the less windy it will be

 

[Weather Boy]

Most of the 00z EPS going for centre of next Monday's deep low to be no further south than Scotland.

 

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_temperature_at_850hpa!132!pop!od!enfo!enplot!2013091100!!/

 

Nonetheless, a rather disturbed pattern evolving from the weekend onwards, as a strong (180mph+) jet comes roaring across the Atlantic, fuelled by a rapid cooling of the air over NE Canada and Greenland interacting with tropical air being drawn north over the NW Atlantic by TS Gabrielle, who's remnants look to be near New Foundland by Saturday morning.

 

Can't help but feel that the 500mb ridge block over Nern Russia/Siberia and troughing further west over Scandi/eastern Europe will keep as in this cool and unsettled flow for the foreseeable aswell.

 

Quite.

 

But it just goes to show how the models can merrily chop and change with impunity, especially the ops.

 

It was only the end of last week (or even early in the weekend) that the models were telling us that we had a pesky trough to push away to our east at the start of this week and then we were looking at a big HP cell building over us from the Azores/mid-Atlantic to give us a shining end to the summer and start of autumn.

 

What is now shown could hardly be more different?  Whilst a very unsettled weekend now looks certain, especially for the north, who's to say that we won't have a complete turnaround for next week compared to what is currently shown?  I agree, though, that the signals suggest otherwise, but that's at the moment.

 

Frosty's HP dominated final third of the month being HP dominated and settled is looking a fairly long bet now - but it could still happen!

[Summer Sun]

Those in places like Lerwick are in for some lively weather early next week with the first storm of Autumn looking very likely now

 

 

UKMO's take on it

 

 

UKMO at t144 looks similar to this morning t168 from ECM (on the right)

 

 

If GFS is right most of England and wales would escape the worst of the winds where as UKMO has the center of the low much further south

Edited September 11, 2013 by Summer Sun

[draztik]

The MetO continues to show a very unsettled spell on the way, particularly for northern & eastern areas.

MetO 12z @ 96, 120 & 144

[DAVID SNOW]

unfortunately, autumn storms like the one being modelled for sun/mon will hurt or kill people and cause £millions of damage, stopping ferry services, disrupting transport and damaging peoples homes and businesses, I would rather embrace the warm and anticyclonic weather later in the month thanks.

 

You may get what you want regarding a settled spell as we move later into September,seems the GFS is keen on this idea.

 

PS wishing for mega heatwaves with temps in the upper 30s would also lead to people dying, probably many more than an autumn storm.

[Frosty.]

 

Frosty's HP dominated final third of the month being HP dominated and settled is looking a fairly long bet now - but it could still happen!

That was based on what the ensemble mean charts have been showing for many days now and the daily met office updates, it's still unclear how much or how fast the recovery will be once the autumn storm clears away from the far northeast next week.

Edited September 11, 2013 by Frosty.

[Frosty.]

 

PS wishing for mega heatwaves with temps in the upper 30s would also lead to people dying, probably many more than an autumn storm.

All I wish for is one more warm spell and then I will switch my attention to potential cold, as for wishing for mega heatwaves in summer, the majority on here want that too, we did well this year.

[Captain Shortwave]

GFS and GEM trying to get the Azores high back in around the 19th September

 

 

Whether anything meaningful comes of this is another question but at least signs today that the trough might shift away by day 8 as opposed to the limpet set up on yesterdays ECM

[DAVID SNOW]

All I wish for is one more warm spell and then I will switch my attention to potential cold, as for wishing for mega heatwaves in summer, the majority on here want that too, we did well this year.

 So you agree with TwisterGirl81 then, the difference being she seems to like stormy weather in autumn as much as you like mega heat in summer or severe cold in winter(as many others do) all these extremes with have a detrimental effect on people

 

Sorry Mods, last one from me.

[No Balls Like Snow Balls]

You may get what you want regarding a settled spell as we move later into September,seems the GFS is keen on this idea.

 

PS wishing for mega heatwaves with temps in the upper 30s would also lead to people dying, probably many more than an autumn storm.

 

Even if this settled spell were to happen all the current 500mb anomolies point to main heights being to the West of the UK.

Certainly can't see no September heatwave / Indian summer or what ever you want to call it.  Looks average maybe slightly above if your lucky. And don't rule out any troughs appearing at short notice to.

[draztik]

The MetO long term has been hinting that settled weather is more likely during the latter stages of Sept and into October, so the gfs and gem may well verify in some fashion.. tho ill be waiting for the ecm, before I consider the possibility of a return to 12 uppers which the GEM is trying to suggest at t204, from the West.

Edited September 11, 2013 by draztik