Model Output Discussion - 31/8/14 Onwards.

[ANYWEATHER]

Little change from the output tonight ,with ecm and gfs still showing a pivitol change by Tuesday for the south and then extending North. Detail is impossible to forecast, but the Rollercoaster is now heading downhill...    

[Polar Maritime]

Little change from the output tonight ,with ecm and gfs still showing a pivitol change by Tuesday for the south and then extending North. Detail is impossible to forecast, but the Rollercoaster is now heading downhill...    

 

It is AW, But going by the Models it's going to be a slow process.

[phil nw.]

It is AW, But going by the Models it's going to be a slow process.

Yes very much so I think PM.

A look at the NH pattern shows the main troughing upstream over Canada setting up shop now and remaining into next week.

A very quiet Atlantic still modeled with just that Iberian cut off low the only sign of anything unsettled, possibly bringing showers into the sw later.

The blocking Scandinavian high the main feature for some days ahead yet.

The latest ECM mean at day 10

http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=1&map=1&type=1&archive=0

Shows little change to the overall pattern with that ridge to our east still showing.

[knocker]

The anomalies tonight are more or less as mentioned above. Blocking HP lying, with slight variations east to west with the resident low pressure to the south west. No great movement in the Atlantic with the jet running around the Canadian low and south of the low off of Spain.

 

The key vis a vis the surface analysis is the exact position of the surface HP and LP.  Notice the HP, particularly on the GFS, is orientated more NW/SE. This tends to push the surface circulation more southerly with the resultant increase in surface temps. They could in fact get quite high although of course at this range this is pure speculation. Interesting tho.

 

 

[gottolovethisweather]

As I've not been browsing the model outputs myself, I had a quick scan through the latest thoughts and aside from one or two comments on here seemingly to the contrary, it looks set fair and dry for nearly all of us for another good six to seven days at least.

This then takes us past mid-September and who knows, the current generally calm and dry interlude might yet extend into the final third of September. This leads me to a comment I made on the Hurricane Cristobel thread on the 27th August and I quote.................................

 

"A threesome of fun and games right there. The odds are surely in our favour at least, for the chance of there being another Ex-hurricane come towards us before Autumn's out. A long way away yet and just when will the Hurricane season end this year? Would't surprise me if it didn't continue into January this time around. I'm favouring a prolonged drier spell at some point, whether in Autumn or Winter but of course these ex-Hurricanes would soon put an end to that prediction, lol."

 

 

Elsewhere on the forums I might add, I did make a prediction that Temperatures would reach 30c in some favoured spots come early September but, yeah well, nobody's perfect   and to my credit, some forecasts at that time suggested it was feasible. 

 

Anyway regarding my quoted comment, the Hurricane season is not yet showing its' true colours with all the associated inaction in the Atlantic, however, I feel this is precisely where our observations need to be focussed over the coming days and weeks if things are to change any time soon.   All eyes on any intense lows consistently popping up in the short to mid-range.

Edited September 10, 2014 by gottolovethisweather

[knocker]

Well the latest tropical storm shouldn't bother us the 12Z GFS has it nipping towards Greenland and the 18z run has it here and the rest hasn't loaded yet. Of course the track isn't written in stone.

 

 

[gottolovethisweather]

Well the latest tropical storm shouldn't bother us the 12Z GFS has it nipping towards Greenland and the 18z run has it here and the rest hasn't loaded yet. Of course the track isn't written in stone.

 

De ja vu.   To my eyes, the mid-Atlantic high seems to be halting any progress of the Atlantic fronts, according to those charts too. Could well be 20th September onwards before a broader change to the general pattern occurs, aside from the showery bits due SW of us nudging into southern parts of England. Not all bad news if you ask me. 

Edited September 10, 2014 by gottolovethisweather

[Polar Maritime]

The GFS this Morning once again shows the Atlantic being held at bay out in the run. With settled conditions persisting for a good time yet with only week fronts pushing up from the S/W, Bringing showers towards the end of the run. As i and others said last night, It looks like a very slow breakdown with no immediate effect for now. 

Edited September 11, 2014 by Polar Maritime

[IDO]

The GEFS show good agreement on the next 6 days with a couple more days of higher pressure then a steady fall in pressure: 

 

Some members still suggesting HP may recover but the mean keeps it between 1010-1015mb till D16. So it looks all change in synoptics.

 

Again it looks more showery than washout and of course the placement of the low towards Iberia/Biscay Bay will promote a warmer flow and the 2m London temps confirm this:

 

 

As well as inter model agreement, x-model there is strong similarities even at D7.

 

GEM:   GFS:   ECM: 

 

By D10 the trough is over the UK with the associated LP system. It is a slow slack affair which is mostly cut off from lower heights to the NW,  but plenty of potential for heavy downpours from convection, though too early for specifics.

 

D10 GEM:   GFS: 

 

After D12 on the GEFS lots of variety due to where the ex Tropical Storm tracks. No clear signals at the moment for that time scale. Again ECM all over the place after D7 flipping between an active trough to a cut off upper low. Today by D10 they are now back to a more active trough:

 

 

So a slow change from the weekend as pressure slips & by D6 more unsettled, though warmer days and nights, with the likelihood rainfall will be more south centric. Lots of uncertainty after D10 with the West Atlantic showing signs of a more active storm season so models may struggle:

 

 

Not bad in the short term with another 7-10 days of pleasant weather.

[Polar Maritime]

Yes the ECMWF is now showing the Atlantic making inroads during it's last few frames.. The last quarter of the Month does look like being less settled/warm. To what extent the Atlantic makes in-roads remains to be seen.

 

Edited September 11, 2014 by Polar Maritime

[knocker]

These two charts are just an adjunct to my post of last night regarding a possibility of some high temps. Stressing possibility.

 

[knocker]

Latest on TS and then it fizzles out. Don't believe a word of of.

 

[mushymanrob]

oh my...

 

 

 

building agreement that something pretty warm could engulf the uk after midweek next. the anomaly charts too support or allow for these charts to manifest.

 

one of the best ever thunderstorms (15/9/1973) came off similar charts.

prepare to sweat though, IF these charts become reality not only will it be warm/hot, but very humid too. i recall 1973's event as being like a pressure cooker!

[TonyH]

Bring it on it would be fantastic for this lovely warm Autumn spell to go out with heat and potential thunderstorms!

[Frosty.]

As Delia Smith famously said at a norwich match some years ago..where are you..let's be having you..where are you? no comments since 2.46 pm..where are you  

 

As for the latest models, the fine and pleasantly warm spell is set to carry on but there is an increasing risk of an odd shower, especially in the east this weekend and into next week but high pressure stays in control for the reliable timeframe but with a lot of cloud at times, however, FI shows a gradual change to unsettled weather from the southwest with low pressure spreading northeastwards into at least the south and west of the uk, the northeast may stay dry next week.

Edited September 11, 2014 by Frosty.

[mushymanrob]

Not much to discuss frosty... Its very settled and theres nothing much happening, best just enjoy the warmth.

[Frosty.]

Not much to discuss frosty... Its very settled and theres nothing much happening, best just enjoy the warmth.

It's interesting you mentioning the warmth because the latest met office update isn't hinting any unusual warmth next week, indeed, they say the settled spell will fade out later next week with unsettled weather spreading from the southwest by 2nd half of next week, it's another case of some modelling showing potential hot and humid weather and then the met office saying temperatures just above average..there is a big low down to the southwest and it appears to be heading our way and impacting on the uk by midweek onwards.

[IDO]

Not much change from this morning.

 

A slack trough moving slowly to the SW with its associated low now staying in situ near the Bay of Biscay, and it is not till about D5-6 that showers hits the UK, the SW first, from the far edge of the low. This continues for around 4 days; as the Biscay low fills and erodes. The unsettled (hit and miss) weather coincides with warmer weather for the south (22-24c) and it promises the north may stay drier.

 

The models this evening around D9 then hint at a return to higher pressure:

 

GEM  ECM  GFS: 

 

The control from the GEFS also goes this way and the hi-res are leading the way for a recovery in pressure. London ens:

 

 

Not complete agreement but a good signal, though it is only a recent development so a few more runs to clarify. Looking at the T300 GEFS there is very little sign of a resurgent Atlantic so September looks like it will be continuing fair. ECM has flipped back again tonight away from the more active trough to the NW at D10 of this morning's run.

 

JMA update yesterday for the 20-27th September also has a positive anomaly to the north and lower heights to the SW of the UK: 

 

So again no sign of a return of the Atlantic. Week 3-4 from JMA also may suggest the end of the month will remain relatively quiet:

 

 

 

 

 

[Frosty.]

Not much change for now but there will be a big change to unsettled next week..something is happening..changes are afoot next week, at last, something different to talk about instead of benign pleasant warmth and rather cloudy weather..hooray

Edited September 11, 2014 by Frosty.

[Scorcher]

It's interesting you mentioning the warmth because the latest met office update isn't hinting any unusual warmth next week, indeed, they say the settled spell will fade out later next week with unsettled weather spreading from the southwest by 2nd half of next week, it's another case of some modelling showing potential hot and humid weather and then the met office saying temperatures just above average..there is a big low down to the southwest and it appears to be heading our way and impacting on the uk by midweek onwards.

 

The thing is with that setup it's difficult to see how it can't be warm to very warm, those lows over the Bay of Biscay always bring warm air over us so it certainly won't be cool. And progress seems to be slow with the low stalling somewhat in the Bay of Biscay rather than moving towards us, so it could remain warm for some time.

[knocker]

The anomalies still pretty much in agreement  The main players the HP lying a shade N of an east/west orientation Greenland to eastern Europe and the resident low just off of Spain. The GFS makes a bit more of this low than the others. The other low still Hudson Bay area and the jet still running around south of the Spanish low.

 

The surface analysis of this has the surface high slightly more east of late allowing, or because of, more encroachment of the low to the south west into the UK. Consequently the surface flow veers more to the south west introducing moister air which combined with the above average temps introduces the possibility of convective outbreaks. But at this stage that's merely conjecture.

Edited September 11, 2014 by knocker

[Frosty.]

The thing is with that setup it's difficult to see how it can't be warm to very warm, those lows over the Bay of Biscay always bring warm air over us so it certainly won't be cool. And progress seems to be slow with the low stalling somewhat in the Bay of Biscay rather than moving towards us, so it could remain warm for some time.

I'm only quoting what the met office are saying, pretty underwhelming from them really but they do have the extra data we don't see in the public domain such as mogreps. I also think the cloud amounts could scupper the type of heat which some output has shown today, by mid september we rely more heavily on the sun being out combined with warm uppers, so if it's rather cloudy, temperatures on the warm side but only a little above average is what we would get. The MO are sounding rather confident of a transition taking place next week from settled to unsettled which would also put a cap on any possible heat..IMO there are signs of the settled spell crumbling from midweek onwards for at least the south and west.

[joggs]

Make most of these good looking synoptical charts.Fast forward 3 months and swap the highs with the lows lol.

[legritter]

I'm only quoting what the met office are saying, pretty underwhelming from them really but they do have the extra data we don't see in the public domain such as mogreps. I also think the cloud amounts could scupper the type of heat which some output has shown today, by mid september we rely more heavily on the sun being out combined with warm uppers, so if it's rather cloudy, temperatures on the warm side but only a little above average is what we would get. The MO are sounding rather confident of a transition taking place next week from settled to unsettled which would also put a cap on any possible heat..IMO there are signs of the settled spell crumbling from midweek onwards for at least the south and west.

Just popped in for a look at todays charts and Data and it certainly could be our last shot at a bbq weekend before autumn proper sets in during next week ,a very unusual synoptic set up as of late what comes next ,Mother nature is amazing ,but lets enjoy this period of calm while we can 

[knocker]

Just out of interest a quick look at the ECM weeklies. I comment not

 

 

Edited September 12, 2014 by knocker