Model Output Discussions 12z 01/09/2016

[knocker]

One doesn't want the ecm to be correct as it's showing 70-80Kt gusts for NW Scotland Tuesday evening and very similar 24 hours later.

Edited September 23, 2016 by knocker

[mulzy]

24 minutes ago, Frosty. said:

I don't necessarily agree, in my opinion the Gfs / Gefs has been better overall in recent times, the ecm and ukmo could be barking up the wrong tree..together!

Of course. Time will reveal all

Do you have any evidence to back this up? Consensus and the verification stats consistently show the ECMWF as significantly better.

Edited September 23, 2016 by mulzy

[Frosty.]

2 minutes ago, mulzy said:

Do you have any evidence to back this up? 

Nope I don't 

I just hope the Gfs is right!

[I remember Atlantic 252]

1 minute ago, Frosty. said:

Nope I don't 

I just hope the Gfs is right!

me too Frosty, but ECM just looks more realistic, although Sept 29th hoping too early for Autumn proper

[Frosty.]

Just now, I remember Atlantic 252 said:

me too Frosty, but ECM just looks more realistic, although Sept 29th hoping too early for Autumn proper

Well..I can remember countless times when the Ecm has been wrong and especially in winter when it shows dream Fi charts that never verify

Anyway, I think the Gfs has improved since its upgrade and its had its fair share of victories against the Ecmwf.

I still think next week wont be bad across southern uk.

 

[bluearmy]

The appearance of ex TS/hurricanes in the n Atlantic are always a tricky conundrum for the models to resolve. I often wonder if, perversely, the increased resolution of the ec op, makes it over react to this increase in 'energy' into the modelling. Hence, depressions become over blown. of course, the extra resolution could well be resolving the situation more accurately. Only time will tell. 

[knocker]

The 4-8 anomalies do show some differences in the upper air pattern which could account for some of the det, differences. Although the general pattern is similar the the ecm makes a more of the trough to the north and suppresses the Azores HP and weakens he trough in the western Atlantic. The result a strong westerly flow with the jet whipping around the North American ridge more or less straight across the Atlantic portending systems impacting the UK. The GEFs has the upper flow backed a tad with the azores pushing further north which could well influence any systems to track further NE.

[Frosty.]

I don't know what all the fuss is about the Ecm 12z, it's just normal early autumn weather, scotland is most affected but they are used to a bit of wind and rain!

Anyhoo, the Ecm 12z ensemble mean doesn't look bad next midweek or by day 10, just like the op..as i said earlier, the south escapes the worst of it..as far as I'm concerned winter can't come soon enough! full speed ahead to the silly season

[blizzard81]

4 minutes ago, Frosty. said:

I don't know what all the fuss is about the Ecm 12z, it's just normal early autumn weather, scotland is most affected but they are used to a bit of wind and rain!

Anyhoo, the Ecm 12z ensemble mean doesn't look bad next midweek or by day 10, just like the op..as i said earlier, the south escapes the worst of it..as far as I'm concerned winter can't come soon enough! full speed ahead to the silly season

It looks increasingly likely that the first full week of October/into second week could be very settled and pleasant. Blocky conditions (sorry for terrible terminology) in October are a very positive harbinger of a cold winter to come. History is no lie.

[Frosty.]

3 minutes ago, blizzard81 said:

It looks increasingly likely that the first full week of October/into second week could be very settled and pleasant. Blocky conditions (sorry for terrible terminology) in October are a very positive harbinger of a cold winter to come. History is no lie.

I hope you're right, especially about winter! :- )

[MP-R]

10 minutes ago, blizzard81 said:

It looks increasingly likely that the first full week of October/into second week could be very settled and pleasant. Blocky conditions (sorry for terrible terminology) in October are a very positive harbinger of a cold winter to come. History is no lie.

With the exception of last year and 2007.

[Man With Beard]

3 hours ago, Frosty. said:

I don't necessarily agree, in my opinion the Gfs / Gefs has been better overall in recent times, the ecm and ukmo could be barking up the wrong tree..together!

Of course. Time will reveal all

Don't forget the false promises of the GFS this summer, all on exaggerated Azores High pushes ...

[Cheshire Freeze]

15 minutes ago, Man With Beard said:

Don't forget the false promises of the GFS this summer, all on exaggerated Azores High pushes ...

Big departure from the 12z at days 6 and 7

More unsettled and much chillier feeling

[knocker]

Today.

Mainly fine in England and Wales and quite warm in the east but with more cloud and wind picking up in the west/ In contrast N. Ireland and western Scotland will be very wet as the front slowly drags itself SE, a process that won't be completed until Sunday for the rest of country introducing a cooler showery regime.

The GFS

A depression tracks NE early next week to be midway between Iceland and Scotland 992mb by 12z Tuesday. With the associated f fronts lying across he UK some wet and windy conditions, particularly in the north. The low moves away east leaving a westerly, showery regime with the next depression tracking east to be be Faroes 982mb by 18z Thursday bringing more rain and strong winds, again particularly in Scotland. Only the SE being immune to this. And so on through the weekend.

[knocker]

A quick glance at the 12z and 00z GEFS anomalies illustrates the downgrading of the Azores influence.

On a more general note Sidney isn't bothering to hide his nuts so looks increasingly like a warm and wet one.

[knocker]

Dartboard

[Frosty.]

1 hour ago, knocker said:

Dartboard

I like darts..bring it on!

It looks like proper autumn weather is on the way.

[phil nw.]

Well after it's more settled and warmer outputs up to yesterday it appears GFS has now moved closer to the ECM modeling for next week with changeable weather spreading further south and the Azores high further away.

Day 5 from the 00z op runs. GFS/ECM/UKMO.

  

The 3 main models all now showing the Atlantic trough digging further south with lows swinging northeast between Iceland and Scotland so wind and rain at times over the coming period,especially for Scotland and N.Ireland but most of us seeing more unsettled weather at times.

Temperatures though on the whole not far from average in the south westerly pattern but some warmth still possible on the odd day or so in the south where we see some ridging between the frontal systems.

We do now appear to be moving into a more mobile pattern as we enter mid-Autumn with a growing influence form the nearby Atlantic jet,yet nothing out of the ordinary I would say.

 

[Frosty.]

Looking at the Gfs 12z, it really doesn't look bad across the southern half of the uk for most of next week as high pressure builds in close to the south, there is plenty of fine weather further south with most of the wind and rain brushing across northern uk at times. It then briefly becomes more unsettled generally from the NW but actually most of low res it's an improving situation as high pressure builds in across the uk and migrates to the north before centering over the uk once again with chilly nights bringing an increase in mist and fog but dry bright days..could be a lot worse!

[Frosty.]

Both the ukmo and gem 12z show the south of the uk largely escaping the unsettled weather next week, most of the wind and rain would be further n / nw whereas the s / se would have a lot of pleasant weather..although the gem then shows a brief NWly incursion into next weekend, high pressure soon builds in and T+240 shows another taste of summer further south with a continental airflow..all in all, the 12z output shows a n / s split with the north and specifically n.Ireland and scotland bearing the brunt of the unsettled weather.

[blizzard81]

All the models but especially ECM struggling to reconcile the potency of the atlantic storms with the strength of the azores high. The 12z outputs going back to the idea of a much stronger azores high. This is the correct idea imo leading to a largely settled first half of October.

[Frosty.]

The GEFS 12z mean shows a north / south split next week with the south of the uk missing most of the unsettled weather with more in the way of pleasant conditions with northern uk having most of the wind and frontal rain...and then as we head into early October, pressure rises generally across the uk with a fine spell for most if not all of the BI..so it doesn't look bad at all across the south.

[Frosty.]

As with the rest of the 12z output, the Ecm 12z shows the north / northwest of the uk catching most of the unsettled weather during the week ahead with largely pleasant conditions across the s / se but then the trend is for the more unsettled weather across the n / nw to swing in from the w / nw to affect the rest of the uk towards the end of the run but always worst further north / west... some very useable weather looks likely further south for a sizeable chunk of next week.

[blizzard81]

4 hours ago, blizzard81 said:

All the models but especially ECM struggling to reconcile the potency of the atlantic storms with the strength of the azores high. The 12z outputs going back to the idea of a much stronger azores high. This is the correct idea imo leading to a largely settled first half of October.

GFS 18z firming up on the trend. I expect to see more firming up across all the output tomorrow.

[knocker]

The GFS continues the unsettled theme for this week, including the weekend with the usual caveat that the wet and windy weather does gravitate to the northern and western part of Britain with the south and east, under some influence from the Azores HP remaining drier, albeit not completely. Thereafter ,from the beginning of next week, it does promote a temporary blocking scenario with HP initially rising from the SW then establishing to the east thus keeping the Atlantic at bay. A not unfamiliar scenario but whether any credence can be given to this remains to be seen although the GEFS anomaly does indicate some support.