Model Output Discussion - 31/8/14 Onwards.

[knocker]

I see this mornings GFS has the Greenland trough further east bringing low pressure via Atlantic into play. A bit of a knife edge but interesting to see how this pans out.

 

[mushymanrob]

not so sure about next weeks high being any more sunny then this dull affair

 

 

those fronts dont bode well for sunshine, at least early on.

 

some disagreement for late next week/mid-month , some runs suggest more high pressure, but the noaa 8 -14 day anomaly appears to be sticking to this solution

 

 

which supports this gfs chart

 

 

itll be interesting to see if this becomes reality , assuming the noaa sticks to this solution.

Edited September 5, 2014 by mushymanrob

[Summer Sun]

UKMO shows high pressure retuning next week with plenty of dry weather though cloud amounts could be high at times like this week, day time temperatures would be warm but nights could become chilly with some mist and fog patches possible

 

 

t144 850's unavailable at the time of posting

 

Edited September 5, 2014 by Summer Sun

[Frosty.]

The Ecm 00z op is a very pleasing run this am, unlike last night's 12z, the polar front jet is well out of harms way to the north, it's that azores low we need to keep an eye on. High pressure domination next week and eventually we import warmer continental air with temperatures into the mid 20's celsius across the south..BBQ weather in mid september...BBBBBBBBAAAANNNKKK

[knocker]

The ECM EPS weeklies going for an unsettled zonal flow.

 

 

[Frosty.]

312 hours away is a long way out

[Frosty.]

Looking at the more realistic timeframe..the Gfs 06z op run shows an increasingly warm anticyclonic spell next week, we tap into much warmer weather from the near continent and southern uk could be into the mid 20's celsius during the 2nd half of next week. Low res shows a gradual descent into less settled weather, especially further north west but I still think the azores high will have a significant influence as we head towards mid month...next week looks very summery on this run

[knocker]

312 hours away is a long way out

 

Good grief. I wonder whether ECM realise that when they produce these monthly forecasts.

[Summer Sun]

UKMO once again shows settled weather returning next week, warm by day and chilly at night, variable cloud amounts with some mist / fog patches overnight / early morning

 

 

only 850's available currently are t96 & t144

 

Edited September 5, 2014 by Summer Sun

[mushymanrob]

312 hours away is a long way out

make your mind up mate, you were the one championing looking into fi to spot trends, or does that only apply to favoured weather types?

the noaa 8-14 dayer supports that fi chart, is this not an emerging trend?

[Frosty.]

make your mind up mate, you were the one championing looking into fi to spot trends, or does that only apply to favoured weather types?

the noaa 8-14 dayer supports that fi chart, is this not an emerging trend?

FI is good for trend spotting but showing a chart and then not giving a proper explanation about it's chances of verifying is poor IMO. And right now i'm more interested in the realistic timeframe which is looking summery although nights will be cool for a time..

Edited September 5, 2014 by ajpoolshark

[IDO]

FI is good for trend spotting but showing a chart and then not giving a proper explanation about it's chances of verifying is poor IMO. And right now i'm more interested in the realistic timeframe which is looking summery although nights will be cool for a time..

 

 

I am grateful to see ECM D13 charts as these are not open to many of us. So thanks Knocker. 

 

These FI charts are what the NOAA 8-14 dayers are based on along with the respective means.

 

FI has been trying to bring a less  settled picture back in for a while, GFS and GEM as well as ECM. However the GEFS at T300 suggests that the Atlantic remains blocked by a dominant Azores; mean:

 

 

So at the moment the continuation of the slack mix of troughs and ridges look likely, with the finer details as to strength and positioning to be resolved. Week 3 and 4 of the latest JMA output ties in with this possibility, no strong anomaly over the UK:

 

 

In the more reliable, the next 6 days looking dry for most. After that the GEFS are still showing spread:

 

 

But even with lower heights never far away, like GEM; the troughs are mostly relatively weak affairs, so settled rather than an Atlantic washout looks the more likely outcome for most, even after D7:

 

   

Edited September 5, 2014 by i'm dreaming of...

[ANYWEATHER]

make your mind up mate, you were the one championing looking into fi to spot trends, or does that only apply to favoured weather types?

the noaa 8-14 dayer supports that fi chart, is this not an emerging trend?

Yes indeed he was making a point to me about spotting trends in FI [fantasy island]!!! I have not viewed the latest ecm, but gfs shows the slack pressure theme well into next week ,with some weak disturbances, but as you say , we could well be looking at a pattern change from mid month onwards. !

Edited September 5, 2014 by ANYWEATHER

[ANYWEATHER]

The slack pressure pattern continues for the next week, then a pivitol time for the models at T+168, with the jet stream gathering momentum! Ecm agrees , gfs does not and out to T+240 both models resemble something from the Atlantic... The Proverbial " Chocolate Teapot" comes to mind     

Edited September 5, 2014 by ANYWEATHER

[Frosty.]

Following the coolest August for 20 years, thanks mainly to Bertha which really threw summer out of sync and making for a very disappointing month compared to june and especially july which was superb. September has finally shaken off the hangover from august and brought a return to more summer like conditions and tonight's Ecm 12z op run carries on the summery theme throughout next week with high pressure in control, nights on the chilly side for a time to remind us it's early autumn but pleasantly warm days with good sunny spells and scattered fair weather clouds, as the high gradually drifts further east, we pick up a warmer flow off the near continent which brings increased daytime warmth, perhaps mid 20's celsius for the south and generally milder nights. Towards the end of the run there is an unsettled blip, perhaps with thundery showers but the azores high is ready to build in soon after..another summery reboot as we head to mid month and beyond?..I hope so

Edited September 5, 2014 by Frosty.

[knocker]

There is reasonable agreement between the anomalies in the 6-10 period.

 

Essentially Trough Greenland with a weak low of NW of Spain. High pressure to the NE stretching towards another HP west to central Atlantic.A split jet stream aiding and abetting slow pattern changes. NOAA 8-14 tending towards a more zonal flow. No point in surface detail at this range but generally HP mid Atlantic and to NE with a slack pressure area over the UK.

 

EDIT that should have read 'west to central Atlantic' of course.

Edited September 6, 2014 by knocker

[Polar Maritime]

A cool Northerly showing on the 15th on tonight's GFS.. 

 

Edited September 5, 2014 by Polar Maritime

[harryc]

A cool Northerly showing on the 15th on tonight's GFS.. 

 

No doubt it will be gone by the morning.

[Polar Maritime]

No doubt it will be gone by the morning.

 

Yes, Models showing some flamboyant output as of late further in the run's. They do tend to lean to more unsettled weather by mid-month, But we shall see.

Edited September 5, 2014 by Polar Maritime

[knocker]

Purely as a matter of interest the GFS anomaly for Friday is much the same the as previous but just taking it further west it shows the trough of the US. A slight difference between our 850mb temp anomaly and the US.

 

[Captain Shortwave]

The models this morning are suggesting that the Atlantic may struggle to break the current settled pattern down.

Pretty representative of the day 6 charts from the GFS/GEM as well with low pressure deepening to our south west as cold air digs south into the Atlantic, the high stays put near or over the UK.

There is little for me to suggest that the high will shift significantly any time soon, or even if it does then we may see a new Azores ridge build in as the GFS ens show.

Higher than normal pressure showing in FI for the UK. So the potential is there for the benign conditions to continue well into the middle and latter part of September.

[knocker]

Looking at the ECM ops for next shows HP domination but nor that warm with about average temps.

 

Edited September 6, 2014 by knocker

[Frosty.]

The GFS 00z op run shows anticyclonic conditions really digging in next week thanks to a large blocking scandi high with variable cloud, sunny spells and light winds. Temperatures dependent on sunshine amounts with low 20's c for the sunniest areas, but high teens c where it stays cloudier, chilly overnight under clear skies with a risk of fog patches. Into the following week, pressure leaks away slowly with an increasing risk of showers, heavy and thundery and starting to feel warmer & more humid and then a thundery trough moves in from the southwest and hangs around for a while before gradually filling in situ.. the run ends warm and settled in the south but notice how the polar front jet is swinging down from the north west..maybe a sign that genuinely autumnal weather could make an impact during the 2nd half of september.

[phil nw.]

It's looking pretty settled for next week with high pressure rebuilding across the UK after the current low towards ne Scotland fills.

Midweek picture from all 3 operationals

 

 

so after the weekend a largely dry and pleasantly warm outlook with some sun but inevitably at this time of year patchy overnight low cloud  or mist may take some time to clear from some spots.

Some suggestion that low pressure over the Azores will approach the south west towards the end of next week with some rain.This could just be a temporary break though as later GEFs favour a rebuild of pressure from the Azores by the end of week 2.

No immediate sign of a general change to more unsettled Autumnal weather yet then with a relatively quiet Atlantic outlook continuing.

[Summer Sun]

UKMO continues to show high pressure dominating next week warm by day with variable cloud, chilly by night, some mist / fog patches overnight and early morning but these would soon burn away

 

Edited September 6, 2014 by Summer Sun