Model Output Discussion 18z 28/07/13

[phil nw.]

A new thread then to continue with discussions from the evenings outputs.

 

Let's try and keep on topic and respectful to each other.

Remember people can see things somewhat differently and if you feel the need to disagree then respond in a friendly manner preferably with some data to support your views.

Let's cut out the point scoring ,it's childish and undermines the quality of the thread.

 

OK thanks all-carry on with discussion below.

 

 

[Man With Beard]

ECM ensemble mean has actually increased the heat for Friday - yesterday and this morning the 16C line covered Kent, but now it covers all of the SE with Kent in the 18Cs, the 20C line just 50 miles away

Clear trend for high pressure to push back in on Sunday

[Captain Shortwave]

Breakdown slower on the pub run, 16C uppers still over East Anglia even by Saturday afternoon

[East_England_Stormchaser91]

Wow, what a GFS rolling out again. Actually see an area of high pressure develop right over the UK after the breakdown of what is likely to be thundery rain and some violent thunderstorms in the East. Quite remarkable really!

[Swave Snow]

It seems in middle FI on the GFS 18z a low develops in situ over the uk but thats way out and unlikely to verify on the day 

 

 

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=336&mode=0

[MP-R]

As much as I love high pressure and wish it would get a move on and come back while some of us are still young, I wouldn't say anything is certain after the plume on Thurs/Fri - possibly the point where FI begins at the moment. It would appear the latest model runs want to bring in warmer air over more of the UK than before with the highest temperatures reserved for the southeast (28-30C) possibly more but even 24-28C further west, decreasing in a northwesterly direction.

 

The GFS 18Z does build some sort of high pressure after the plume but so much has chopped and changed from run to run it's hard to tell as flabby low pressure is never too far away.

 

In the reliable, an unsettled few days to come with heavy downpours and thunderstorms tomorrow before a warm front makes itself known on Tues/Weds introducing warmer air from later on Wednesday onwards.

[TonyH]

There has been a clear trend for high pressure over UK Sunday and into early next week.

[DTHFCJ]

There has been a clear trend for high pressure over UK Sunday and into early next week.

agree 100%..the ECM ensembles mean have been showing this for a while.....be they right or wrong they are showing it

 

also...

http://www.meteo.psu.edu/~fxg1/ECMWF_12z/test8.gif

http://www.meteo.psu.edu/~fxg1/ECMWF_0z/test8.gif

 

trough there yes but nothing like the last several summers...i know before im told wait for 3 or more runs.....etc etc

Edited July 28, 2013 by BALE1

[phil nw.]

Some posts from last night have been deleted because they were sarcastic and/or having a dig at other members content.

You know who you are.

This is becoming tiresome and shows disrespect to the team and the membership-please cut it out and simply put your views without jumping all over others that don.t see things the same way.

Come on peeps let's keep this thread on topic so we can enjoy reading it without the sniping.

 

Thanks.

Edited July 29, 2013 by phil nw.

[Captain Shortwave]

Discrepancies about the longevity of the plume aside (ECM still wants it longer than the GFS/UKMO). Both GFS and ECM agree on the Azores high wanting to take greater control of the weather over the UK

 

 

Later frames of the ECM throws hot air northwards again

Apart from the next couple of days, there doesn't seem to be much rainfall, especially in the South and East.

Edited July 29, 2013 by Captain shortwave

[Frosty.]

I like the Ecm 00z for the week ahead, the Hot Plume pushing up from the south with a very hot and sultry spell after midweek through to next weekend with scorching sunshine and a threat of scattered homegrown intense thunderstorms or continental storms with temperatures in the east and southeast into the 90's F, into the 80's in most other areas for a while, the ecm then becomes messy with small high's and flabby shallow troughs but the reliable timeframe brings another blast of continental summer heat for the second half of this week. The ukmo 00z also brings the heat, as does the gem, navgem and gfs. 

 

In the meantime, today brings a classic mix of sunshine and heavy, slow moving thundery showers, tomorrow looks dull and wet across southern england but the sunshine and showers mix elsewhere, then an active warm front pushing north during midweek with a band of heavy rain but hot, sultry continental S'ly to SE'ly winds following. remaining unsettled, warm and humid in more western & northern areas with outbreaks of heavy rain but with drier sunnier gaps inbetween.

Edited July 29, 2013 by Frosty039

[wimblettben]

Wow, what a GFS rolling out again. Actually see an area of high pressure develop right over the UK after the breakdown of what is likely to be thundery rain and some violent thunderstorms in the East. Quite remarkable really!

I wouldn't get my hopes up about it. We all remember what happened the last time we had some supposed thundery rain affect us.

 

It is also still quite a way out in model terms, we still need to see a lot more runs yet before we can be confident about it happening and then get excited about it.

Edited July 29, 2013 by wimblettben

[johnholmes]

It is not often that over 3 days the 3 main anomaly charts show such differences. In this case it is ECMWF-GFS showing one idea and NOAA in its 6-10 and 8-14 another version.

NOAA suggests an upper trough as the main player whilst the other two have increasingly gone for less trough and more ridge type.

As to which is correct or nearer the mark then to me it is impossible to say. These differences may well account for variations in the synoptic models over the last few days and expect similar for a few days yet. Eventually the weather will decide which way it is going. It makes for interesting model watching whichever variation you choose.

[joggs]

It is not often that over 3 days the 3 main anomaly charts show such differences. In this case it is ECMWF-GFS showing one idea and NOAA in its 6-10 and 8-14 another version.NOAA suggests an upper trough as the main player whilst the other two have increasingly gone for less trough and more ridge type.As to which is correct or nearer the mark then to me it is impossible to say. These differences may well account for variations in the synoptic models over the last few days and expect similar for a few days yet. Eventually the weather will decide which way it is going. It makes for interesting model watching whichever variation you choose.

Yes ive noticed to John,i bookmarked the link to these charts months ago and am an avid follower and urge people to really follow these over time!.Sorry thats if your talking about the 500mb charts?.I still urge people to take them on board Edited July 29, 2013 by joggs

[Alexis]

Anyone else unable to get the ECMWF on Wetterzentrale? I can only get it on Meteociel.

[johnholmes]

Yes ive noticed to John,i bookmarked the link to these charts months ago and am an avid follower and urge people to really follow these over time!.Sorry thats if your talking about the 500mb charts?.I still urge people to take them on board

 

I am slowly getting a few folk to at least look at them. Without wanting to sound as if I am talking down to anyone, I am thinking of trying to do a post explaining how to use them, when they give good guidance, when not, what they actually show etc?

 

In terms of the current output they are fairly different as I've posted earlier today. The next thing tp put a spanner in the model works will be if the hurricane season really gets going next month and onwards. In spite of different models being quite good at both predicting their track and development or non development into the Caribbean or Gulf of Mexico, they are less good once these things get into the Atlantic. The huge amounts of vapour involved must have something to do with it I feel and the very large changes in heat content as they change from tropical-hurricane-ex storms and transfer into the less warm sea areas, and the colder air the further north they get. Interesting though as most things meteorological are.

[Paul]

Anyone else unable to get the ECMWF on Wetterzentrale? I can only get it on Meteociel.

 

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

[Paul]

Ok, we're going to try something new today  - this thread is going to 100% without personal point scoring or snide comments aimed at other members. We're going to achieve this with a pretty simple setup - if your post contains any of the above (or similar) then without further warning we'll remove your ability to post into here. There are just a handful of people this post applies to really, so the majority can safely ignore it and do so in the knowledge that their model thread viewing will be much more model related and much less ego/sniping related from here on in..

 

Thanks

 

Paul

[shedhead]

The last 3 runs have somewhat downgraded the heat potential from the Thu/Fri plume, which was perhaps not unexpected considering there will be no real build up ahead of it.  What is of more surprise to me this morning however is the building of pressure next week by both GFS and ECM, but as JH alluded to earlier there is a fair bit of uncertainty within the 6-10 and 8-14 day 500mb anom charts, so this can no more be relied upon than the lowering of pressure shown quite consistently up until last night imo.

 

As is often the case, more runs are needed.

Edited July 29, 2013 by shedhead

[TEITS]

Temps widely predicted to be between 28-30C on Thursday. If you then take into account some locations will always reach a few degrees higher then 32/33C isn't out of the question.

 

http://cdn.nwstatic.co.uk/gfsimages/gfs.20130729/06/84/ukmaxtemp.png

 

This time though locations such as Heathrow, Northolt are unlikely to be the hotspots as this could be further N i.e Northants, Cambs.

 

The outlooks continues to look promising also.

[Captain Shortwave]

06Z pushes the Atlantic trough through much quicker hence the heat is less intense and lasts less time, in fact it's worse than this mornings UKMO output. 

We still have a split which involves Friday and Saturday, GEM and ECM want to keep the heat for longer and have a more intense push than GFS/UKMO, this is due to heights pushing further north.

GFS T90

 

UKMO

 

ECM 

GEM

Notice how even at this time frame there is quite a difference, GEM/ECM have a much bigger push on the ridge to our east than the other two which slows the trough down and allows the heat to have a more northwards push.

Still a lot to be decided. Strangely there is more confidence in the conditions over the UK at day 7 than the days preceding it as there is good agreement for weak heights to build over the uk

Based on the output today, I have an increasingly feeling that next week will see high pressure building just to our north with low pressure developing over Iberia. The two upper ridges will link up and cut off the trough to our west and that will sink south-eastwards.

Edited July 29, 2013 by Captain shortwave

[shedhead]

GFS 06 maintains the general theme of building pressure early next week, especially across the north, so perhaps a new evolution is emerging.

Edited July 29, 2013 by shedhead

[joggs]

I am slowly getting a few folk to at least look at them. Without wanting to sound as if I am talking down to anyone, I am thinking of trying to do a post explaining how to use them, when they give good guidance, when not, what they actually show etc?In terms of the current output they are fairly different as I've posted earlier today. The next thing tp put a spanner in the model works will be if the hurricane season really gets going next month and onwards. In spite of different models being quite good at both predicting their track and development or non development into the Caribbean or Gulf of Mexico, they are less good once these things get into the Atlantic. The huge amounts of vapour involved must have something to do with it I feel and the very large changes in heat content as they change from tropical-hurricane-ex storms and transfer into the less warm sea areas, and the colder air the further north they get. Interesting though as most things meteorological are.

Great idea John(your first paragraph) i think that will really be a massive help to people.Also your musings about the hurricane season that may crank up.Appreciate it. Edited July 29, 2013 by A Boy Named Sue

[joggs]

Sorry i dont know why my above post has mixed with JH post.I quoted correctly but my reply has tagged on to his!.Thanks abns!

Edited July 29, 2013 by joggs

[shedhead]

06Z pushes the Atlantic trough through much quicker hence the heat is less intense and lasts less time, in fact it's worse than this mornings UKMO output.

We still have a split which involves Friday and Saturday, GEM and ECM want to keep the heat for longer and have a more intense push than GFS/UKMO, this is due to heights pushing further north.

Notice how even at this time frame there is quite a difference, GEM/ECM have a much bigger push on the ridge to our east than the other two which slows the trough down and allows the heat to have a more northwards push.

Still a lot to be decided. Strangely there is more confidence in the conditions over the UK at day 7 than the days preceding it as there is good agreement for weak heights to build over the uk

Based on the output today, I have an increasingly feeling that next week will see high pressure building just to our north with low pressure developing over Iberia. The two upper ridges will link up and cut off the trough to our west and that will sink south-eastwards.

Careful what you wish for CS, you may well end up getting the dreaded E or NE'erly back in Gt Y.

Edited July 29, 2013 by shedhead