Model Output Discussion - 31/8/14 Onwards.

[knocker]

The ECM does come up with some bizarre anomaly/contour charts. For the moment I'm taking a rain check on analysis (Tescos calls) I'll just call the scenario, 'in limbo with 91L entering stage left'.

Edited September 9, 2014 by knocker

[MR EXTREMES]

its a very interesting start to autumn and nice to here the omega block being used,

last time i herd the omega block term used was 09/10 autumn into winter.

some pretty impressive warmth possible if the gem and ecm are to be correct.

 

its looking very promising so far for later autumn into early winter if this kind of pattern holds firm.

although this is a long way of in terms of weather.

[Summer Sun]

For most high pressure continues to dominate on UKMO though into next week winds begin to come in from an east to SE'ly direction so the far south west could become more prone to some rain but else where its shown to remain dry and relatively warm by day

 

[knocker]

Perhaps a boat trip to the Scillies.

 

[Man With Beard]

www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=306&y=141&ville=Londres

More warmer (+10c 850s) than cooler members for week 2 on the 06z ensembles - pretty dry throughout - and a few runs that which could push us back to the 25c mark or higher, cloud/wind permitting. Just a couple of 'cold' runs in there. So above average temps / below average rain favoured until D10, and possibly even further out.

[mushymanrob]

its a very interesting start to autumn and nice to here the omega block being used,

last time i herd the omega block term used was 09/10 autumn into winter.

some pretty impressive warmth possible if the gem and ecm are to be correct.

 

its looking very promising so far for later autumn into early winter if this kind of pattern holds firm.

although this is a long way of in terms of weather.

 

is there an omega block?... where?...

[johnholmes]

is there an omega block?... where?...

 

see post from Jo Farrow yesterday I think it was

 

the link is below

http://www.netweather.tv/index.cgi?action=news;storyid=6135;sess=

Edited September 9, 2014 by johnholmes

[mushymanrob]

see post from Jo Farrow yesterday I think it was

 

the link is below

http://www.netweather.tv/index.cgi?action=news;storyid=6135;sess=

 

ah yes... cheers john.

[johnholmes]

ah yes... cheers john.

 

I am sure Jo would agree it is not the best of examples but it is an Omega block.

[Frosty.]

I don't like posting charts so far out but I must admit, T+384 hours is looking autumnal on the Gfs 06z op run. Most of the run ( all high res and well into low res)  is anticyclonic but eventually the atlantic starts to fire up and send vigorous depressions our way although they struggle to break through the block..but in the end they win with the polar front jet getting to the south of the BI with cool, windy and unsettled weather for all.

[Frosty.]

Just to add to my earlier post regarding the 6z op run, it's fair to say that those type of charts showing proper autumn weather are very few and far between among the GEFS 06z perturbations but what the heck..the pattern has to undergo a gradual or major change at some point so maybe it will gather support.. the 6z mean isn't buying it, there are a lot of blocked anticyclonic charts even in the T+384 hours range so the current pattern may prove very reluctant to give much ground during the rest of september.

Edited September 9, 2014 by Frosty.

[Polar Maritime]

GFS again continues with cooler/unsettled weather from just around mid-month. Not to the extremes of the 00z by a long way, But the theme is still there, And that's all it is atm. 

 

Edited September 9, 2014 by Polar Maritime

[Frosty.]

I really think we could see mid 20's celsius across southern uk during next week with +10 T850 hPa from the continent making inroads, at the same time pressure falls from the south with an increasing risk of showers, some heavy and thundery, this time it's the GEFS 12z mean showing a warm up, I think it's been showing enough times now on various output to give it a good chance of verifying once the scandi high pushes away to the east and the trough arrives from the southwest / south enabling the much warmer and more humid continental air mass to drift north.

[ANYWEATHER]

The beautiful late summer, early Autumn weather is with us for about another week! But at long last and gfs and ecm agree on a change during early next week with pressure falling and unsettled conditions developing from the south next week, ......The North will see the fine weather for the longest.....

[knocker]

No major changes with the anomalies tonight.  Still maintaining the strong blocking high to the north and east, deep low Hudson Bay area, the Azores/Bermuda high poking it's head above the parapet mid Atlantic, the low pressure area adjacent to Spain and the jet cut off at the pass. It's with the Spanish low that  some changes have been postulated for the surface with cyclonic activity moving into the southerly part of Britain replacing the domination of the HP. No point going into much detail about this at this range except suffice it say it could bring some quite high temperatures into the frame and maybe, just maybe, some quite unsettled weather. The NOAA 8-14 doesn't indicate major changes, still maintaining the blocking high and the weakening low pressure to the SW. No major invigorating of the pattern is indicated.

Edited September 9, 2014 by knocker

[damianslaw]

Its a very static picture under a proper blocking high - not had one of these for a long long time, hence expect only a very slow gradual change to unsettled conditions - most likely through next week and unusually from the south. ECM and GFS latching onto the cut off low over Spain drifting north as the central core of the high elongates on a more N-S axis as opposed to w-e which we will see in the next week. All eyes will then be on developments with the Jetstream - heights could very easily collapse into central Europe or remain stubborn but be given a path towards Iceland.. mmm lots of options, but there is certainly no strong signal for an attacking jet anytime soon. September can be exceptionally benign, but this year it seems more benign than ever - could end up being a notably dry month for many (we've had barely a sprinkle so far, and the next 7 days look bone dry).

 

As others have said - if this was January we would be in the freezer. Indeed such synoptics even in 6 weeks time would be delivering preety cold conditions off an increasingly cold continent, alas we are just on the right side of the season for such synoptics to deliver warmer than average conditions as the continent has yet to cool down properly. Mind nights have been properly cold for the time of year in sheltered western parts, many a colder night than last winter in recent days, with lows in the countryside regularly between 1 and 5 degrees under clear skies, and its not a classic warm set up for the time of year neither, but very pleasant all the same.

 

For me I'm only taking occasional cursory glances at the models at the moment - there are certain times when you just know things will be slow to change and this is one of them.. we don't get them often mind.. but they do often occur at this of year it seems more than ever.

Edited September 9, 2014 by damianslaw

[Polar Maritime]

This mornings GFS run is showing some quite warm air being pumped up from the S/W over the UK out in the run, Maybe the Atlantic will be put on hold for a little longer.. The Models are certainly struggling with very mixed signals on offer lately, As expected for the time of year.

 

Edited September 10, 2014 by Polar Maritime

[Frosty.]

The Gfs 00z op run shows high pressure in love with the uk   emphatically in control of our weather until early next week, only then does the scandi high drift further away and pressure falls from the south allowing a trough weakness to extend north with a risk of showers, even a threat of thundery rain pushing north later next week, however, pressure remains high to the north / north east of the uk throughout and then the azores high ridges in and builds strongly across the uk and we are back to high pressure domination once again. Considering we are now into autumn, although some would argue that autumn doesn't start until the equinox, it doesn't feel like autumn and this run shows plenty of summery warmth as we go through the next few weeks with low 20's celsius, occasionally mid 20's c for the south of the uk and even scotland, which tragically may no longer be part of the united kingdom soon is into the low 20's c at times...so it's a summery outlook guys..august was cr*p but september is making up for it

 

Anyhoo..craig thinks this run is FAB-U-LUS

[IDO]

A change is still being indicated for many with the predicted fall in pressure now 4 days away. On the London Ensembles it will take 4 days to fall from 1025 to 1010mb so by no means a dramatic change in surface conditions:

 

 

Less settled but because of the low to the SW temps should pep up:  D9 mean: 

 

The GEFS pressure mean then settles around 1015mb for the rest of FI.  So even with a slack trough somewhere to the SW it now looks like the main thrust of energy from the Atlantic will be kept to the north, so the possibility of washouts have reduced in recent runs. Even the mean around D14 looks good for this time of year:

 

 

GEM from D8 D10 also keeping us in a slack pressure zone between HP and LP dragging in some warm uppers from the south:

 

 

 

ECM similar at D8, but subtle difference with the Atlantic ridge and positioning of the upper low to the SW: 

 

On this run the Atlantic ridge does not mate with the Scandi high on D9 where as GFS and GEM have tentative link ups: 

 

ECM GEM:   GFS: 

 

By D10 ECM has LP over the UK:  Again it should feed in warmer air.

 

Around 33% of the GEFS are in line with this morning's ECM take. This was the split yesterday and although this morning's GFS hi-res are trending towards the Scandic-Atlantic ridge link, there still remains uncertainty from mid-month.

[Summer Sun]

UKMO shows Sunday and Monday continuing mostly dry although starting warm its shown to turn fresher as winds settle in from the east cloud amounts could be high in the east which could see some isolated light showers or drizzle in the east

 

 

By Monday the south is shown to become increasingly prone to some rain / showers with the best of the driest weather for the north fresher for all

 

[knocker]

The ECM is similar to last night and if anything the northern blocking strengthened. This and the trough to the SW still being the main influence of the UK weather with above average temps.

 

[Milhouse]

GFS 12Z- Lots of continental warmth pushing northwards towards the UK throughout next week with low pressure anchored to the SW of the UK. The central slice of the UK looks best placed for fine weather persisting throughout next week. Towards the SW things will turn more unsettled, whilst towards the NE low cloud, mist and suppressed temperatures will once again be a feature.

[Captain Shortwave]

It does look like we will continue to see fair and pleasantly warm conditions for the next week, beyond it looks like high pressure will start to decline somewhat though unsettled weather will struggle to gain the upper hand. There is the potential for a plume event to occur as winds swing more to wards the south east.

We could see a new upper ridge develop to our east which could drive very warm air towards us.

GFS and GEM have the low a little closer to the UK. Worth noting that the GEM/GFS have a tropical storm in the mid-Atlantic whilst the ECM has no storm at the moment.

[Frosty.]

The GEFS 12z mean shows the atlantic knocking on the door later in FI but will it have enough huff and puff to blow the house down?

 

The reliable timeframe is anticyclonic with warm sunny spells and light winds, sunniest in the west with rather more cloud in the east, the scandi ridge holds through the weekend with similar weather to now, still chasing areas of cloud around but there will be warm sunny gaps to enjoy. Next week looks different with the scandi high drifting further away and a shallow trough extending north, this enables a draw of continental warmth to pump north westwards across the uk and southern britain could become very warm and humid with mid 20's celsius, this is not much of a stretch because up until then we will be experiencing low 20's c in favoured spots, however, the trend is for pressure to slowly fall from the south with an increasing risk of showers but v warm and humid for a time before eventually the atlantic systems edge closer as the block weakens...perhaps late september will kick start autumn proper with unsettled and cooler oceanic conditions replacing the current warm, benign pattern...will the atlantic show it's teeth..time will tell

[Polar Maritime]

Yes Frosty, The Atlantic's knocking again after completely dropping the idea this morning, And now delaying the signal.. The GFS hasn't got a bloody clue! Well less than normal..One day eh 

 

Edited September 10, 2014 by Polar Maritime