Model Output Discussion 31/07/14 onwards.

[johnholmes]

The anomaly charts are quite interesting at the moment. Not sure what to make of them really. All 3 are showing changes to their long held view of a marked trough near the UK with an upper ridge to the west. Have a look yoursleves, NOAA first then this morning from EC and GFS.

I need a couple of more outputs from each of them to be sure, maybe not even then, as to what they are indicating.

 

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

Remember this change only occurred in the past 24 hours or so, thus their indications out to about the 3rd week or so of  August are not affected, or that is how I would read them.

below is the one previous to the last issue

[knocker]

I must admit to being a tad confused John as this mornings chart from the ECM doesn't seem to be similar to your link unless I'm missing something.

 

Edited August 17, 2014 by knocker

[Polar Maritime]

Yes the West certainly looks to be winning out this morning after the cool Northerly next week, With any settled spell towards the end of the Month looking weaker and/if only a transient affair as the Polar Vortex wants to set-up over Greenland which will aid to swing Low's South off the Atlantic.

 

Edited August 17, 2014 by Polar Maritime

[draztik]

This forum is usually the best gauge to highlight a change in weather conditions. It has been very quiet around these parts the last couple of days. The numerical models have all but squeezed the life from any lingering hopes that HP would take hold from in/around 20 August; the upcoming week looks much cooler than of recent times with showers for almost everyone. The following week should see us move back towards average temperatures/slightly below with more unsettled conditions persisting into Sept. By day 14, ECM ensembles indicate slight ridging from the Azores which could potentially settle us down - but that is a long way off at this stage.

Days 5-10 height anom/temp anom

Days 9-14 height anom/temp anom

[johnholmes]

I must admit to being a tad confused John as this mornings chart from the ECM doesn't seem to be similar to your link unless I'm missing something.

 

you could be right in that they do look different but then probably taken from different data sets perhaps.

I have never really used those you show K so I really cannot comment on them. 

[mushymanrob]

The anomaly charts are quite interesting at the moment. Not sure what to make of them really. All 3 are showing changes to their long held view of a marked trough near the UK with an upper ridge to the west. Have a look yoursleves, NOAA first then this morning from EC and GFS.

I need a couple of more outputs from each of them to be sure, maybe not even then, as to what they are indicating.

 

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

Remember this change only occurred in the past 24 hours or so, thus their indications out to about the 3rd week or so of  August are not affected, or that is how I would read them.

below is the one previous to the last issue

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifnoaa last 6-10.png

 

indeed they are suggesting a shift from a nearby uk trough with a upper ridge to the west.... but arent they still suggesting an unsettled westerly  into next week ?

 

please correct me if im wrong!

[johnholmes]

indeed they are suggesting a shift from a nearby uk trough with a upper ridge to the west.... but arent they still suggesting an unsettled westerly  into next week ?

 

please correct me if im wrong!

 

they are

[damianslaw]

No post in 7 hours says it all - models not keen on showing a change to settled conditions anytime soon, after tentative signs a couple of days ago there may be a slight change to something more settled before the end of the month, it now looks like the atlantic will win out - meaning a preety unsettled last month of the summer and very disappointing.

[MR EXTREMES]

same thing happened in the summer of 09 but not this early could be good for winter longtime away i know 

[Frosty.]

I think summer as we know it is over, we had an excellent june and july with lots of hot and humid weather but now the wheels have come off and it's turning a lot cooler with low humidity as polar air floods south. This is the best chart I could find on the entire Gfs 12z op run, just a small window of fine weather as a weak area of high pressure drifts across the uk next weekend, BH monday turning wet from the west and then unsettled for most of that week with depressions dive bombing in from the north west..autumn is here early..I hope wintry weather comes early this year too..roll on winter... it's so lifeless on here until winter comes 

Edited August 17, 2014 by Frosty.

[Dancerwithwings]

No post in 7 hours says it all - models not keen on showing a change to settled conditions anytime soon, after tentative signs a couple of days ago there may be a slight change to something more settled before the end of the month, it now looks like the atlantic will win out - meaning a preety unsettled last month of the summer and very disappointing.

There's always hope for a little summer heat still to be had and if EN/GEFS no 5 comes around i certainly won't be moaning

 

 

Edit.....I must admit though things are starting to look a little desperate.

Edited August 17, 2014 by Dancerwithwings

[mhielte]

There's always hope for a little summer heat still to be had and if EN/GEFS no 5 comes around i certainly won't be moaning

 

 

Edit.....I must admit though things are starting to look a little desperate.

 

I agree it is looking rather desperate. At this time it's more apt to look for transient ridges that could lead to a more persistent building of high pressure. The more likely outcome can be deduced by looking at the jet stream forecast...

 

... I think the outcome will be that any high pressure ridging from the south over the coming week or so will stay transient and hopefully a day or so of pleasant conditions can coincide with a weekend day. Perhaps it's the best we can hope for at the moment. The jet is forecast to stay over the UK or slightly to the south whilst the Atlantic continues to feed us with unsettled weather.

 

Those of a convective persuasion might find something of interest to grasp once the northerly gets out of the way *even the showers forecast next week look rather tame!* 

Edited August 17, 2014 by mhielte

[phil nw.]

I agree it is looking rather desperate. At this time it's more apt to look for transient ridges that could lead to a more persistent building of high pressure. The more likely outcome can be deduced by looking at the jet stream forecast...

 

... I think the outcome will be that any high pressure ridging from the south over the coming week or so will stay transient and hopefully a day or so of pleasant conditions can coincide with a weekend day. Perhaps it's the best we can hope for at the moment. The jet is forecast to stay over the UK or slightly to the south whilst the Atlantic continues to feed us with unsettled weather.

 

Those of a convective persuasion might find something of interest to grasp once the northerly gets out of the way *even the showers forecast next week look rather tame!* 

 

Hi mhielte,

Welcome to the forum

Yes a fair summary of the outlook certainly over the coming few days.

The Scandinavian trough only slowly easing away towards the end of the week.

[ANYWEATHER]

I agree it is looking rather desperate. At this time it's more apt to look for transient ridges that could lead to a more persistent building of high pressure. The more likely outcome can be deduced by looking at the jet stream forecast...

 

... I think the outcome will be that any high pressure ridging from the south over the coming week or so will stay transient and hopefully a day or so of pleasant conditions can coincide with a weekend day. Perhaps it's the best we can hope for at the moment. The jet is forecast to stay over the UK or slightly to the south whilst the Atlantic continues to feed us with unsettled weather.

 

Those of a convective persuasion might find something of interest to grasp once the northerly gets out of the way *even the showers forecast next week look rather tame!* 

A very big welcome from all of us at Netweather. I see this is your first post, and what a fantastic first post it is as well. Your contribution will be well appreciated.

[knocker]

you could be right in that they do look different but then probably taken from different data sets perhaps.

I have never really used those you show K so I really cannot comment on them. 

 

I think I realise why John. Just happened to look at the15 day  Control run.

[Captain Shortwave]

Well the Scandi trough does look like easing away, but it does throw another wave of cooler air down on Friday, this along with a strengthening Atlantic jet look to diminish any chance of a completely dry and fine bank holiday.

Saturday looks reasonable, though the UKMO gives a chance of showers in the east.

GFS/ECM look dry.

Sunday shows more divergence with the ECM/GEM going for frontal systems pushing west to east on a strengthening south westerly wind

GFS looks fairer

Monday looks fine and increasingly warm for the east, rain steadily pushing in from the west

Again the ECM/GEM are more unsettled

 

Interestingly the ECM/GEM have thrown up a similar longwave pattern to this week, the only difference is the 500 mile shift west, so if we get here then we could see a considerable warm up with a broad south to south westerly flow setting up in response to robust heights building over Europe and an associated trough developing in the Atlantic. Both ECM/GEM show this

Still rain for the north western half of the UK though.

So there is the chance of an improving picture, especially so the further south and east you are.

 

Before then a mix of sunshine and showers with occasional longer spells of rain with temperatures below normal.

Edited August 17, 2014 by Captain shortwave

[ANYWEATHER]

Two thirds of summer have been excellent. very warm and well above average sunshine hours, and then came along August to put a spoiler on the Summer  Ive got no good news for heat lovers unfortunately, but the briefest of ridges by Saturday. As for summer weather over, Yes indeed, but Im sure there will be some fine weather to come during September and even October.

[mhielte]

Thanks for the welcome 

 

Some excellent summaries of current output above; it really helps further the understanding of our weather for learning amateurs like myself. Given the cold shot next week, a return to average temperatures and the occasional drier/sunnier interlude thereafter might feel quite nice!

 

Captain Shortwave highlights an important difference show on the ECM & GEM tonight. A S or SW flow would lead to predominantly fine conditions for the south and east (in case anyone is off on a late holiday!) 

[Man With Beard]

I agree it is looking rather desperate. At this time it's more apt to look for transient ridges that could lead to a more persistent building of high pressure. The more likely outcome can be deduced by looking at the jet stream forecast...

... I think the outcome will be that any high pressure ridging from the south over the coming week or so will stay transient and hopefully a day or so of pleasant conditions can coincide with a weekend day. Perhaps it's the best we can hope for at the moment. The jet is forecast to stay over the UK or slightly to the south whilst the Atlantic continues to feed us with unsettled weather.

Those of a convective persuasion might find something of interest to grasp once the northerly gets out of the way *even the showers forecast next week look rather tame!*

This jet forecast demonstrates well that August looks in trouble if it's settled warm weather you want. It will be hard for a ridge to build for long enough to pull heat from southern Europe to northern Europe, so even the dry days may have chilly starts and average temperatures. Of course, southern areas only need modest upgrades to see substantially more summery weather, but northern areas increasingly look as if they will go through the whole of August with no hot and sunny days at all

[Frosty.]

They think it's all over....it isn't yet..well not according to the Ecm 12z op run anyway

 

This run shows the magic 564 dam line flirting with the uk again with hot, humid and potentially thundery weather spreading up across the south & southeast..the fat lady is not singing yet.

[knocker]

The ECM ops has got very excited this morning.

 

The anomaly for Sunday has an intense upper low mid Atlantic with a strong blocking high NE America. These two systems funnel the jet around and it ends up bang over the UK bringing a stong westerly pattern for the BH weekend.

 

So, lower than average temps and after the transient ridge on Saturday low pressure moves in bringing unsettled weather

[Captain Shortwave]

"Low pressure moves in bringing unsettled weather"

 

Really?

That's decent for England and Wales, fine and very warm with the 8C isotherm moving in on Sunday and covering England and Wales into the following week with the 12C isotherm pushing into the south midweek.

If the ECM verifies then summer may close on a high.

 

 

The most positive solution this morning but it's pretty close to last nights operational and all in all a decent run for the south as we get the Euro high/Atlantic trough pattern establishing. The GEM barges the high over the Eastern seaboard towards us which results in a different solution and another UK trough before that same high crosses the UK at the end of the run.

The GFS again shows a mostly fine weekend with the approaching low being much slower than the other models.

All the models show heights lowering considerably over Greenland which will drive a pattern change from what we see this week. So probably a westerly pattern establishing but with uncertainties to where the jet will lie. 

Edited August 18, 2014 by Captain shortwave

[IDO]

They think it's all over....it isn't yet..well not according to the Ecm 12z op run anyway

 

This run shows the magic 564 dam line flirting with the uk again with hot, humid and potentially thundery weather spreading up across the south & southeast..the fat lady is not singing yet.

 

 

A D10 chart from ECM? I suppose one will come off eventually. However it had no support last night from its ensembles:

 

No real change this morning with the question mark remaining how quickly the westerly flow establishes after the transient ridge this weekend and how bad BH Monday will be.

 

GEM is the wettest, windiest and coolest: 

 

GFS is not much better with a warm front, preceding the low, crossing the country BH Monday: 

 

The London GEFS graph showing nearly full support for a LP system to cross the UK after the brief ridging of the weekend: 

 

 

A slow moving feature that on the GFS op takes a week to clear the east coast, dragging in 4c uppers to the south coast again with troughs circulating the low. Wet, cool and horrid. Luckily it has minimal support amongst its members. The control is more reflective of its mean with a N/S split with cyclic ridges interrupting the mainly westerly flow.

 

ECM this morning again  tries to amplify the pattern around D7 so the LP system stalls west of Ireland with a build of pressure to the east and west of the fledgling trough. So outcome for BH Monday:

 

  With the jet powering through the UK: 

 

Tuesday week: 

 

By Wednesday a shallow trough edging into the UK with a southerly flow bringing in warmer uppers:

 

 

 

The GEFS have had this possibility as background noise for a few runs, and it remains this morning with a cluster of about 20%. Last night the ECM ensembles had minimal support so we will see later if this has grown or the op is just throwing out its usual D8-10 over amped runs.

 

Next 5 days will be Autumnal but for the south rain should be at a premium with showers possible on a couple of days.

[Frosty.]

A D10 chart from ECM? I suppose one will come off eventually. However it had no support last night from its ensembles:http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifEDM0-240-2.GIF

 

 

 

A D10 Ecm chart has more chance than a GFS D10 chart in my opinion, Ecm is the best model IMO so if the models show it and I think it has a good chance..I will show it!

[Summer Sun]

UKMO offers some hope for a couple of settled days during the weekend with some chilly nights for the time of year before low pressure returns from the west

 

Improvements from the west on Saturday

 

 

Settled for most on Sunday

 

 

With some sunshine and lighter winds it should feel warmer than of late even though temperatures wouldn't be anything special on the thermometer