Model Output Discussion 31/07/14 onwards.

[johnholmes]

I've just come across an earlier guide you did but can't find part 2.

 

I presume I did part 2! Sorry cannot search now as busy packing and away at 4am in the morning so I will take a look in my files when I get back in a week-sorry

 

John

[phil nw.]

The first part of next week looks quite unsettled with the jet across the south.

 

 

rain or showers moving through after the weekend affecting many areas from Monday.

The air somewhat warmer though as winds swing in off the Atlantic with values closer to normal especially further south.

No sign from the GFS ens mean and the NOAA 6-10 day Anomaly forecasts of any change out to day 10 so it looks like Summer ends with something of a whimper

 

 

just brief drier intervals from transient ridging seems to be all we can expect currently as the westerly Atlantic setup is modeled until the last day of August.

 

[summer blizzard]

Euro is shocking for heat fans.

 

[Frosty.]

Tonight's Ecm 12z op run looks generally unsettled with spells of wet and windy weather alternating with slack trough conditions with sunshine and showers, we will shortly lose the cool polar air with temperatures recovering closer to average. The run ends on a very unsettled note but there are times during the run where it should feel pleasantly warm with sunny spells, at least across the south of the uk, 

[Summer Sun]

Euro is shocking for heat fans.

 

 

GEM for the same time brings in some warm air with high pressure close by

 

[ANYWEATHER]

Seems a long time since High Summer ,and the absence of any kind of summer like weather now, Im glad I enjoyed the first two thirds of Summer! And back to the models and ecm brings the rain earlier into bank holiday Monday rather than gfs. Overall, ecm is more unsettled than gfs, but really slim pickings from both models as regards late summer weather. Im sure some places will see some fair weather, but that Big high has gone for now!!! Even in FI[ Fantasy island]  land theres no trend to settled weather...      

[Captain Shortwave]

At this present time I don't feel confident in calling next week weather wise, even Monday. The models do show heights building to the north of the Uk (between Norway and Iceland), but at the same time the jet doesn't move much further south than the English channel. This really puts the squeeze on any low pressure approaching the UK from the west. With this narrow gap, we could easily see the two areas of higher heights close together and stall the Atlantic train, position and length of time are up for debate and the corresponding weather for the UK. For now I think that all options are open as there are a range of solutions on the table from very warm/sunny conditions to a set up similar to what we have now, or even having low pressure parked over the UK.

The fact that some models are calling Monday dry and some are calling a complete washout is enough to put me in doubt for even the semi-reliable timeframe, let alone after that.

Edited August 21, 2014 by Captain shortwave

[Frosty.]

There is no way i'm chucking the towel in with regard to summery weather, not as long as there are 564 dam thicknesses flirting with the south, september and even early october can produce low 80's F..it's not over yet, the fat lady can stay in the wings for a while longer.

[phil nw.]

On the 6z GEFS I spotted a possibility of the jet tracking north Phil with the winds changing to a southerly type. They reckoned on the NOAA prognostic discussion that the 6z ensemble mean of GFS would be the most likely outcome.

No sign of that on the 12z means pji.ECM mean now out day10

 

looking similar to GFS with energy still running well south.

No indication of any buckling of the upstream jet to create an opportunity for the jet to swing north as yet.

 

it looks pretty flat and zonal across NA.

Quote from those discussionsOVERALL THE 500-HPA PATTERN FORECAST OVER NORTH AMERICA  HAS BEEN TRENDING TOWARD A MORE ZONAL PATTERN.

Link.

http://www.cpc.ncep.noaa.gov/products/predictions/610day/fxus06.html

 

There does appear to be less certainty further on into week 2 though with the possibility of some tropical storm development that may shake up the wavelengths across the Atlantic but we are probably looking into September for any effects on us..

[knocker]

Regarding the end of next week the upper air charts are in remarkable agreement  with the trough lying to the NW of the UK and a zonal flow established,

 

The jet running across the south of the UK low pressure is the order of the day in the eastern Atlantic with little sign of warmer weather and the temps about average.

Edited August 22, 2014 by knocker

[mushymanrob]

Euro is shocking for heat fans.

 

 

no it isnt. i think heat fans have long since accepted summers likely to be over and arent expecting anything hot.

[knocker]

At this stage GFS is fizzling the tropical storm out in the Atlantic

 

 

[Frosty.]

The Gfs 00z op run shows much warmer conditions developing during the second half of next week as high pressure builds north and by friday it's dry, very warm or hot with a good deal of sunshine across much of the uk, the fine and very warm weather lasts into the following weekend across the eastern side of the uk. Another burst of summery weather with the 564 dam line making significant inroads into the southern half of the uk, yes it's just one op run but it shows the potential..I hope lucy get's her perfect wedding weather on the 30th, got my fingers crossed for you

[Polar Maritime]

Yes Frosty, The GFS has been hinting at this transient affair for a good few days now, Which could bring some warmer more settled weather for the South, Before the next Low spills in from the West again bringing cool/wet conditions for the start of Autumn. 

 

[phil nw.]

A slightly different overview of the ever changing Northern Hemisphere upper air pattern.

 

2 images showing the jet stream and upper level flow-the left one is now and the right one for T72hrs.

 

We can see the current chilly northerly coming down across the UK from the Scandinavian trough gradually being replaced by slightly warmer Atlantic air after the weekend as the approaching little ridge moves across us through Sunday..

The ridge backs the winds towards the south west by Monday as the next low comes in with it's attendant rain.

 

With this wave train we are set to remain more on the colder side of the general pattern next week so no great warm up yet but temperatures should get closer to normal with the loss of this week's Arctic feed.

 

A glance at T144hrs.

 

shows the next ridge after Mondays low moving across round mid-week.

 

I think these give a good idea of the Atlantic mobile pattern modeled for the next 5-6 days with that southerly tracking jet and the changeable weather expected from day to day.

 

 

[Polar Maritime]

I have just had to delete a post, Can we please only discuss Model Output in here, And respect others personal take on the Models, With-out the constant 1 liners about personal thoughts.

 

Please continue.

 

Many Thanks, PM 

Edited August 22, 2014 by Polar Maritime

[Frosty.]

The Gfs 06z op run delays the high from the south by 24 hours at the end of next week compared to the 00z and also restricts it's influence to the south eastern quarter of england but the run is full of potential for very warm weather at times with a humid, thundery outbreak into early september and even the last chart to me looks full of potential for continental heat to drift our way. As it is, the 564 dam line, which I regard as the holy grail in summer, has been shunted as far south as spain, is on it's way back to the south of england during the course of next week, it won't take much of a change synoptically to bring a nationwide summery spell at the end of august as the 00z op run showed..i'm encouraged by the latest output..summery weather ain't over yet.

Edited August 22, 2014 by Frosty.

[TonyH]

Not sure why people persist in describing future outcome hypothesised from the latest GFS?

However there are those that do detail rounded objective cross model interpretation which makes this thread worthwhile. 

Not sure newcomers and people new to weather models could differentiate though.

Edited August 22, 2014 by TonyH

[Polar Maritime]

Not sure why people persist in describing future outcome hypothesised from the latest GFS?

However there are those that do detail rounded objective cross model interpretation which makes this thread worthwhile. 

Not sure newcomers and people new to weather models could differentiate though.

 

Because it's the Model Output Discussion, There is nothing wrong with describing what the latest GFS run is showing as per Frosty's post above describing the latest Gfs 06z op run. Which helps new-comers abbreviate what each run is showing, Those who make cross model interpretations would display numerous charts from across the Model suit, And would describe there reasoning's just like I'm Dreaming of.. for example. 

Edited August 22, 2014 by Polar Maritime

[Methuselah]

Because it's the Model Output Discussion, There is nothing wrong with describing what the latest GFS run is showing as per Frosty's post above describing the Gfs 06z op run, Which helps new-comers abbreviate what each run is showing, Those who make cross model interpretations would display numerous charts from across the Model suit, And would describe there reasoning's just like I'm Dreaming of.. for example. 

Right answer!  

[Frosty.]

Because it's the Model Output Discussion, There is nothing wrong with describing what the latest GFS run is showing as per Frosty's post above describing the Gfs 06z op run, Which helps new-comers abbreviate what each run is showing, Those who make cross model interpretations would display numerous charts from across the Model suit, And would describe there reasoning's just like I'm Dreaming of.. for example. 

Exactly PM..and I really believe there is a window of opportunity for a much warmer and more settled spell later next week, I don't really mind once we get well into september since the nights draw in faster but again there is potential for yet more summery spells during early autumn but i'm hoping we have a more active autumn this year, the problem last year was the sluggish benign pattern we had through september and october before autumn got going, and then it never stopped until march..proper autumn this time please and followed by a proper winter with lots of snow and frost.

Edited August 22, 2014 by Frosty.

[Polar Maritime]

Exactly PM..and I really believe there is a window of opportunity for a much warmer and more settled spell later next week, I don't really care once we get into september but again there is potential for yet more summery spells during early autumn but i'm hoping we have a more active autumn this year, the problem last year was the sluggish benign pattern we had through september and october before autumn got going, and then it never stopped until march..proper autumn this time please and followed by a proper winter with lots of snow and frost.

 

I agree there Karl, But let's try and keep the discussion based around what the Models are showing  

Edited August 22, 2014 by Polar Maritime

[Thermohaline Conveyor]

Here we go again, another Bank Holiday weekend has creeped up on us and many people will want to know what days they can get out and about and what days they need to assign the “Duvet Dayâ€.

 

 

Bank Holiday Saturday 23rd August

 

We start with Saturday. Generally it won’t be too bad. The West will be best, the East – well not so great. It certainly won’t be a washout with low pressure exiting out across the North Sea and allowing high pressure to temporarily build into the South West.

 

Mainly dry with variable amounts of fair-weather cloud across South West England and Wales. Elsewhere sunny spells and enough energy in the atmosphere to spark off one or two showers, these mainly isolated further South and West, but more frequent and heavier towards the North and East. The highest risk of a heavy shower will be across Yorkshire and North East England.

 

Temperatures will continue below average for the time of the year with a range of 12ºC to 15ºC in the North and 15ºC to 18ºC in the South. Cool under the cloud and pleasant enough in any sunny breaks.

 

 

Bank Holiday Sunday 24th August

 

Sunday is perhaps the best day of the lot if you wish to get out and about or do some early washing.

A mainly dry day across many parts of England, Scotland and Wales with variable amounts of fair-weather cloud and some sunny spells. The best of the brightness will be across Scotland with a little less cloud and a little more sun.

 

Despite the mainly dry and pleasant start to the day an area of low pressure will begin to bring weather fronts into South West England, Western Wales and North West England by late afternoon/evening with increasing cloud and eventually some patchy rain moving in.

The rain eventually becoming heavy and more persistent later in the evening and overnight before spreading across many parts of England and Wales during Monday. Turning breezy too.

 

Generally temperatures will not be too bad with a range of 16ºC to 20ºC in the South and a cooler 12ºC to 15ºC under a cooler aimass across Scotland.

 

 

Bank Holiday Monday 25th August

 

Lets start with the good news. Scotland will experience a mainly dry, fine and pleasant day with variable amounts of fair-weather cloud, quite breezy with some nice sunny spells. Just a slight chance of the odd isolated shower.

 

As for the rest of England and Wales bands of rain will move in from the Atlantic as an area of low pressure becomes slow moving. A mixture of patchy rain which could become persistent at times will clear through some areas to make way for heavy scattered showers which could be locally thundery in nature. Generally a very unsettled day is expected with further rain likely to spread in across Southern areas later in the day.

 

Temperatures academic in the South across much of England and Wales with a range of 15ºC to 18ºC and pleasant enough under the brighter and drier skies further North across Scotland with a range of 13ºC to 16ºC.

 

That’s all for now, have a great weekend.

[Weather-history]

 Bank Holiday Monday 25th August Lets start with the good news. Scotland will experience a mainly dry, fine and pleasant day with variable amounts of fair-weather cloud, quite breezy with some nice sunny spells. Just a slight chance of the odd isolated shower. .

Unfortunately, it's not a bank holiday in Scotland.

[Thermohaline Conveyor]

I know Weather History, but I can't leave you guys out.  That would be unfair.