Model Output Discussion 31/07/14 onwards.

[Summer Sun]

UKMO starting to show a more settled end to next week

 

 

Temperatures around average for most maybe slightly above in parts of the south

 

[Frank Trough]

GFS now falling into line with Euros post Bertha. GFS has really struggled to shift the low heights - it often does that but it is now waking up. No heatwave but hopefully a gradually improving picture after tomorrow's antics.

 

decent chart for the sout coast. Bournemouth beach would be sheltered and packed if that comes off.

[IDO]

GFS now falling into line with Euros post Bertha. GFS has really struggled to shift the low heights - it often does that but it is now waking up. No heatwave but hopefully a gradually improving picture after tomorrow's antics.

 

decent chart for the sout coast. Bournemouth beach would be sheltered and packed if that comes off.

 

A bit harsh on the GFS bearing in mind that even this morning ECM 0z had the track of Bertha wrong! Tonight it has the current track consensus. As for what happens after Bertha has blown itself out in the trough, there remains lots of uncertainty after D5. Cool and unsettled till around Thursday for sure then lots of spread, eg GEFS pressure:

 

 

However with a Typhoon hitting the Pacific this should create a wave effect as the pattern becomes meridional so I would expect a pressure rise, though probably a 3-5 day transient ridge:

 

 The typhoon in the Pacific.

 

 NH becomes more amplified.

 

I suspect it will not be a longer pressure build as we no longer have the block to our NE/east to stall any ridge.

 

So expect changes over the next 2-3 days with regard to next weekend. Already next Friday ECM tonight has brought 4c uppers down to the south coast on a NW'ly flow:

 

And GEM for next Friday still has the UK under the trough with a cool flow: 

 

 

I know UKMO has a ridge build in by Thursday but after its recent performance I would not be using that model to compare others by.

Edited August 9, 2014 by i'm dreaming of...

[Frank Trough]

A bit harsh on the GFS bearing in mind that even this morning ECM 0z had the track of Bertha wrong! Tonight it has the current track consensus. As for what happens after Bertha has blown itself out in the trough, there remains lots of uncertainty after D5. Cool and unsettled till around Thursday for sure then lots of spread, eg GEFS pressure:

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgraphe4_0000_265_188___.gif

 

However with a Typhoon hitting the Pacific this should create a wave effect as the pattern becomes meridional so I would expect a pressure rise, though probably a 3-5 day transient ridge:

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgfsnh-0-6.png  The typhoon in the Pacific.

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgfsnh-0-96.png  NH becomes more amplified.

 

I suspect it will not be a longer pressure build as we no longer have the block to our NE/east to stall any ridge.

 

So expect changes over the next 2-3 days with regard to next weekend. Already next Friday ECM tonight has brought 4c uppers down to the south coast on a NW'ly flow:

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifECM0-144.gif And GEM for next Friday still has the UK under the trough with a cool flow: 

 

http:////f1.nwstatic.co.uk/forum/public/style_images/tctc91_simplify/attachicon.gifgem-0-144.png

 

I know UKMO has a ridge build in by Thursday but after its recent performance I would not be using that model to compare others by.

 

don't get me wrong, the GFS has clearly handled Bertha the best out of any of the models - i'm talking about afterwards. I think the GFS sometimes has a tendancy to overdo the longevity of low heights - remember the Mid july breakdown it touted consistently (it had a trough domintaed 3rd week for about 5 days before imploding along with it's entire ensemble suite)? The operational has now decided that Friday looks decent in the south - not that different from the ECM, possibly now a little bit more optimistic.

 

The UKMO looks best but given all other output but as you say, it's probably being a tad excitable.

[ANYWEATHER]

Post bertha, and models show a cool and unsettled spell, Im a little bit hesitant to call any detail from the models in the medium term, but models are really struggling later next week to show any detail, it seems the waters need to clear after bertha !

[Frosty.]

Tonight's Ecm 12z op run shows a window of fine and warmer weather for the south later next week into the weekend with temperatures not far from the mid 20's celsius, progressively cooler and less settled further north. Although it's looking more generally unsettled for the next 5 days or so, temperatures should still get into the low 20's celsius for the south / southeast with the best of the dry and sunny spells between bouts of more unsettled weather but closer to mid to high teens c across the north and west with more frequent spells of rain interspersed by sunshine and blustery showers, windiest across the north next week but winds easing by midweek.

 

In the meantime, batten down the hatches for Bertha, there will be locally strong winds for the time of year with gusts to 50 mph around some exposed coastal areas and we will all see a period of heavy rain spreading from southwest to northeast tonight & tomorrow, followed by drier, brighter weather from the south later but with scattered heavy showers. 

Edited August 9, 2014 by Frosty.

[lorenzo]

Kabooom

 

Flatline..

 

Interesting to see where we go from here, loose blocking prominent to NNW, subsequent jet dialling in with similar story to Bertha track, just how long can it get stuck for.

 

Mr Huffmans tropical analogs for the MJO, ( very interesting to see them update as per amplitude - wonder what led that on.. hahahaha attached to the off a cliff falling GWO, neither the lead anomaly so a status quo of sorts. 

 

Just a perfect recipe for the Atlantic to crank up a gear or two and lock in an Autumn jet..

 

This winter is going to be a rammy.. imagine we get caught on the right side of this.

 

 

 

 

[Panayiotis]

Theres ex Bertha taking the Alternative Track 2, which the Met gave 10% probability, well done to the GFS for constantly giving the signal for this evolution.. 

[mushymanrob]

This looks a bit like the Azores high to me?

 

 

... now post the rest of the run... cherry picking the warmest chart from any run is misleading. that shows that we might get a small window of relief from what all models show is a very unsettled outlook.

next week is looking autumnal, with cool temps and strong winds moderating as the week goes on. the best we can hope for is that temps return to average, the southeast being most favoured. but theres no sign of any return to settled warm dry weather that we have enjoyed through most of the last 2 months, and that is the reality of the situation.

[Captain Shortwave]

Decent agreement for an improvement at the end of this week.

Should give a window of 2/3 days of decent pleasant weather as the Azores high ridges in.

Before then there will be showers or longer outbreaks of rain for many with temperatures around or a little below average.

Beyond this things look a little complex with rather cold air trying to dig south from the arctic and warm air trying to be pushed north from the cut off low in the Atlantic. 

[Frosty.]

The Gfs 00z op run shows lots of fine & warm weather for the south but with some unsettled, less warm spells, it shows progressively cooler and more generally unsettled weather further north but with fine and warmer intervals from time to time. The week ahead looks unsettled with sunshine and showers, some heavy and thundery but feeling pleasantly warm in the sunny periods with temperatures close to 70F, a bit higher for the south / southeast at times but cooler when longer spells of rain occur. Into next weekend, high pressure builds in across the south bringing very warm and sunny weather for a few days. In general, it's the north and west, especially the north west which look coolest and most unsettled during the next couple of weeks whereas the further south you are, the more chance of decent summery weather can be expected at times..all in all, not bad at all..certainly not as bad as some are painting it.

[ANYWEATHER]

... now post the rest of the run... cherry picking the warmest chart from any run is misleading. that shows that we might get a small window of relief from what all models show is a very unsettled outlook.next week is looking autumnal, with cool temps and strong winds moderating as the week goes on. the best we can hope for is that temps return to average, the southeast being most favoured. but theres no sign of any return to settled warm dry weather that we have enjoyed through most of the last 2 months, and that is the reality of the situation.

Yes fleeting rises in pressure at times, just about sums it up' overall the general broad picture is that of the Atlantic more or less in full control. What will be noticable this coming week even for the south, is that of a dramtic cool down, which especially for the south which has seen high temps for many weeks now.

[Summer Sun]

UKMO continues to move towards a settled spell developing towards the end of the week

 

Pressure will be rising during Friday

 

 

By Saturday high pressure is over large parts of the UK with temperatures around average

 

[knocker]

For next weekend there is not agreement with the GFS and ECM regarding the 500mb anomaly. The ECM has the large trough to the NE stretching further west than the GFS leading to the GFS giving more emphasis to the Azores high. The jet is a fairly weak feature running across Scotland that would tend to suggest no permanent high pressure arrangement. Temps are below normal, significantly so with regard to the ECM

 

Edited August 10, 2014 by knocker

[summer blizzard]

Euro is a slap in the face for anybody wanting a warm spell lasting more than 2 days. Its a glorious run for anybody wanting cool though.

[IDO]

GEFS still showing about 5 days of cooler uppers, 3-4c below seasonal average and with the flow from the NW certainly feeling cooler most of the this week: 

 

Pressure then will rise according to all models, around Friday/Saturday: 

 

ECM op has about 35% support for the ridge to edge in Friday for 2-3 days (Southern bias) and is the top cluster. The 2nd and third cluster (over 40%) support the ridge  for about 12-24 hours later.

 

At the moment this looks being only transient with ECM op and mean bringing down colder uppers, again so by D10:

 

 

 

GEM also seeing this signal: 

 

The GEFS suggest next weekend is still uncertain, the op is one of the most progressive with the pressure rise, about 33% keep us in lower pressure by Saturday and the majority cluster is closer to the ECM with a brief ridge favouring the south. ECM at D5 have six clusters so I assume they are also showing variations for the weekend.

 

Further on in FI shows massive scatter with the op showing a ridge over the UK and the control showing a trough:

 

 

 

 

[mushymanrob]

For next weekend there is not agreement with the GFS and ECM regarding the 500mb anomaly. The ECM has the large trough to the NE stretching further west than the GFS leading to the GFS giving more emphasis to the Azores high. The jet is a fairly weak feature running across Scotland that would tend to suggest no permanent high pressure arrangement. Temps are below normal, significantly so with regard to the ECM

 

indeed, but the noaa charts have been consistent and trend more towards the ecm, leaving the gfs as an outlier.

 

 

[ANYWEATHER]

Awfull August weather at least for the week ahead,    

Edited August 10, 2014 by ANYWEATHER

[IDO]

This evening both GEM and ECM have moved closer to the GEFS, making much less of the temporary ridge suggested for next weekend. Although the pressure recovers after the low moves away, even London fails to get the mean above 1017mb for Friday-Sunday:

 

 

The further north the less the pressure recovers. ECM for Friday to Sunday on the 12z:

 

 

With the flow from the N/NW and with uppers for most of the UK even next weekend 4c or below, not very seasonal. Even at D10 the ECM has the 4c uppers covering the south coast. The last few GFS runs have been bringing a relative cool spell so this has support:

 

D10 uppers ECM:  GFS mean at D10: 

 

The GFS op is trough dominated till around 25th August. ECM has a weak surface high D8-10 but it looks messy and they keep putting back the pressure rise as it struggles to cope with the current setup. I get the feeling GFS is the one to follow post-Bertha. JMA has also joined the more trough dominated output for week 2. The NOAA 8-14 day showing no sign of a pressure rise for the UK:

 

 

The next five days look cooler than of late with showers predominantly for the west. Though Scotland has fronts spinning around the low for the next three days.

 

[A.J]

Awfull August weather at least for the week ahead,    

depends very much on your locale Ian......for northern districts it doesn't look great but certainly no washout for everyone. gfs & latest FAX goes for a westerly to more north westerly flow as Low pressure migrates to Scandinavia as the week progresses with embedded troughs in the flow leading to more of a north/south split.....cool, and often showery in the north & down the east coast, whilst for southern regions, fresh feeling and breezy with occasional showers with temps hovering in the low seventies as high pressure attempts to ridge in from the south west as we approach the weekend

[Captain Shortwave]

^^ Probably worth putting the UKMO in your analysis there too, again going for the most bullish pressure build over the next weekend.

 

We certainly need to be wary of that cut off Atlantic low. If it ejects back into the Atlantic jet then suddenly the longwave pattern for north west Europe could swing dramatically into a more favourable position.

This is the most positive solution. GFS retrogrades the Azores high, the ECM and GEM both both another blast of cool air down from the Arctic which displaces the high further west though not to the degree of the GFS op and hence builds it back in during week 2. I wouldn't want to call things just yet.

[ANYWEATHER]

For the moment, it looks like ridges get squashed due to the strong jet stream...

[IDO]

^^ Probably worth putting the UKMO in your analysis there too, again going for the most bullish pressure build over the next weekend.

 

 

 

We certainly need to be wary of that cut off Atlantic low. If it ejects back into the Atlantic jet then suddenly the longwave pattern for north west Europe could swing dramatically into a more favourable position.

This is the most positive solution. GFS retrogrades the Azores high, the ECM and GEM both both another blast of cool air down from the Arctic which displaces the high further west though not to the degree of the GFS op and hence builds it back in during week 2. I wouldn't want to call things just yet.

 

UKMO is in my sin bin for a while after recent efforts but the latest UKMO (forecaster's view) update for week 2 follows the GFS route rather than the ECM: :

UK Outlook for Friday 15 Aug 2014 to Sunday 24 Aug 2014:

Probably a good deal of dry weather through the weekend with variable cloud and sunny spells, but cloudier in the northwest with some rain at times. Into the following week, conditions will tend to become more unsettled again with many areas seeing showers or more prolonged rain at times. The showers and rain are likely to be heavy at times, and perhaps accompanied by some quite breezy conditions, especially in the north. Looking ahead to the latter part of this forecast period, further showers or rain remain likely at times, but there are signs that the most frequent bouts of unsettled weather may then be confined to northwestern regions. Daytime temperatures are likely to be close to average, but rather cool at times in the north and west.

Updated: 1200 on Sun 10 Aug 2014"

Though I agree too early to call.

[Man With Beard]

Awfull August weather at least for the week ahead,    

Don't you think its only awful if you want a heatwave? I think away from the NE this will be a mainly dry and sunny week, only weak fronts moving south - and because it is early August I would have thought 20-23C would be the maxes - pleasantly warm and still sleepable at night, maybe a jumper in the morning. A south coast holiday wouldn't be too bad this week.Mind you, those seeking something hot before the end of the summer season haven't a lot of hope aside UKMO - Bertha has pushed the trough into a position where heat is likely to stay bottled up in the med - I can't see any strong signs that this will change for at least 7 days, maybe CS's theory above will come to something but its the outsider.

[IDO]

Don't you think its only awful if you want a heatwave? I think away from the NE this will be a mainly dry and sunny week, only weak fronts moving south - and because it is early August I would have thought 20-23C would be the maxes - pleasantly warm and still sleepable at night, maybe a jumper in the morning. A south coast holiday wouldn't be too bad this week.Mind you, those seeking something hot before the end of the summer season haven't a lot of hope aside UKMO - Bertha has pushed the trough into a position where heat is likely to stay bottled up in the med - I can't see any strong signs that this will change for at least 7 days, maybe CS's theory above will come to something but its the outsider.

 

 

That would be nice but GFS hi-res max out at between 19-21c this week in the south, but much of the country a lot cooler.

 

 

 

ECM mean supports the GFS with more of a trough influence than the op's high:

 

OP:    Mean:

 

But would not take a major pattern shift to improve the outlook.