Model Output Discussion - Mid Summer Onwards

[Mark wheeler]

18z vs 12z just for fun

Edited September 21, 2023 by Mark wheeler

[Cheshire Freeze]

There's a few 100mph wind storm perts in the GEFS around D6

Very low risk I'd say, but probably worth keeping a passing eye on over the next day or so

Edited September 22, 2023 by Cheshire Freeze

[Frigid]

22 minutes ago, Cheshire Freeze said:

There's a few 100mph wind storm perts in the GEFS around D6

Very low risk I'd say, but probably worth keeping a passing eye on over the next day or so

The GFS really went from warm anticyclone to cyclogenesis. Complete flip on what was showing a few days prior. 

[RJBingham]

10 hours ago, LRD said:

Don't worry - spring starts very soon after on the 14th Dec... according to the CFS 6z! 

BANK 

[I remember Atlantic 252]

3 hours ago, RJBingham said:

BANK 

EH? that will be dark and cloudy, probably drizzle too, now you wouldn't like that in summer would you? so what's the difference

[ANYWEATHER]

5 hours ago, Frigid said:

The GFS really went from warm anticyclone to cyclogenesis. Complete flip on what was showing a few days prior. 

That's what happens when you follow the daily dose of model watching! I dare say the scaremongering storms that the gfs and indeed any other computer model FI output will be watered down nearer the time.....

[mb018538]

About as typical as you can get for the UK in an Atlantic driven pattern. 4-8 inches of rain over the hills and mountains of the NW and a flooding risk....gradually getting drier as you head further SE. Wonder when the 'We're still in drought' messages start appearing again?

Edited September 22, 2023 by mb018538

[johnholmes]

Friday 22 September with NOAA and ECMWF

Not too different in UK area to Tuesday although trough less sharp and smaller –ve height values but some variations in far west, +ve heights Hudson Bay area still about the same but trough down west coast less marked. Flow into UK from s of west with border area contour around 558 DM (564 Tuesday), negative heights within trough about the same.

ECMWF 28-2Oct shows fairly cold air in deepish nw’ly 500 MB trough slowly warming out and becoming a more westerly flow. The surface flow also weakening  and changing the flow from n of west to more westerly as a ridge develops and moves in off the Atlantic. At the same time the 850 MB temperatures slowly cool down as the +5 C moves from an alignment Borders west Wales to a more west-east central Wales to the Wash.

Both models seem fairly similar during a similar time frame, 6-10 days from now. The 8-14 NOAA is not majorly different with main troughs west coast N America and east Atlantic with a broad westerly between.

Overall it would suggest showery with a spell of more unsettled and rather windy weather  slowly easing down to a nw-se split with the se being drier and less unsettled, temperatures around what we would expect at this time in autumn.

Climate Prediction Center - 8-14 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

[minus10]

Gfs0z wanting to settle things down for the beginning of October with the help of another tropical system..

..while of course its FI and at the top of the pressure ens..

...its not a complete outlier and is plausible given current weather pattern...

...eventual uptick on 850s..

...even the mean showing higher pressure for beginning of October ..particularly for the south..

...so although this is just one option i think after the unsettled period prior most people would welcome an autumnal spell of mists and mellow fruitfulness...

 

[northwestsnow]

Strong signal for temps to be above average across Europe from now to week 6 which will be the first week of November.

 

 

[alexisj9]

10 hours ago, Cheshire Freeze said:

There's a few 100mph wind storm perts in the GEFS around D6

Very low risk I'd say, but probably worth keeping a passing eye on over the next day or so

As it's the GFS I'm not worried yet, hopefully they tone down as usual. There will be a bigger temp gradient from cold air to warm air than usual though, with how warm the sea temps are. So I do expect a stormy autumn

[Harveyslugger]

21 minutes ago, alexisj9 said:

As it's the GFS I'm not worried yet, hopefully they tone down as usual. There will be a bigger temp gradient from cold air to warm air than usual though, with how warm the sea temps are. So I do expect a stormy autumn

Ukv now showing it aswell 108+ gust(mph) for Ireland

[Harveyslugger]

Latest ukv going for a severe storm Wednesday 108+mph gusts

[Penguin16]

47 minutes ago, northwestsnow said:

Strong signal for temps to be above average across Europe from now to week 6 which will be the first week of November.

 

 

Revolting.

[MattStoke]

10 minutes ago, Penguin16 said:

Revolting.

Given the warming global climate, and particularly in Europe, temperatures averaging out above the historical average isn't really surprising.

[legion_quest]

Not to mention the warm seas. There is a post in the Winter thread showing just how warm, and in some places 'hot' the seas are in comparison to what they should be, along with the stark statement "The oceans presently have, and are expected to retain, a configuration without modern analogue." So what that does to the weather will be anyone's guess with no truly comparable data for the models to compare and model against. 

[Cambrian]

Any ambiguity about the extent to which the models have shifted this week is neatly removed by looking at the ECM weekly mean pressure anomalies for 25 September to 2 October.

Charts for that week from Saturday 16th (at day 9-16) and from yesterday (at day 4-11). 

 

That’s a very different week on offer now compared to the outlook last weekend.

Similar trend emerging for the following week. 

 

There are hints of the trough easing somewhat as we get into October in the 0z ECM and 6z GFS means for day 10, at the end of the week featured above, with pressure being bumped up a bit from the south, 

 

though to varying degrees, the corresponding ops aren’t on board yet!

 

Hopefully not seeming too negative for those seeking some reliably fine weather, but my feeling for the models we’ll be looking at over the next few days is that the ops past day 5 will do what ops past day 5 do and throw up occasional high pressure for us to enjoy looking at, gone on the next run, and the trough will look to ease somewhat with time through the medium range, as it gets averaged out in the means, but then be firmed up as the time draws nearer. 

We’ll likely get the odd, transient ridge in the gaps between frontal systems drawing up some heights from where they are plentiful, and yes, the NW-SE lower to higher gradients that we often see will be a factor during the coming period, but the fundamental underlying pattern for the UK and Ireland through next week at least is to be primarily influenced by sustained Atlantic troughing, and that in the event, this pattern may well continue to be reinforced into October. 

Have a great weekend. 

PS - very early days I know, but on all these NH charts, look where the fledgling PV is looking to set up…..interesting!

Edited September 22, 2023 by Cambrian

[TSNWK]

1 hour ago, northwestsnow said:

Strong signal for temps to be above average across Europe from now to week 6 which will be the first week of November.

 

 

Nice...  no point it being below average  in late October/ early November keep it mild as possible then to save on the bills...

[damianslaw]

An unsettled pattern for the foreseeable. The atlantic trough the dominant feature sending in pulses of heavy rain and not really moving from its position just to our west. A flow predominantly from between west and south, once tomorrow's ridge clears through - good timing falling on a Saturday. Make the most of it especially in the west, the rest of the month set very disturbed, with bouts of wind and rain. A very wet September now in the offing, what a contrast to those first 10 days.

Staying fairly mild, but under the wind, rain and cloud away from the SE, won't feel pleasant. Autumn has set in fully. The seasonal switch has set in bang in time for the equinox. 

Edited September 22, 2023 by damianslaw

[Porto]

The 06z GFS throwing a quite intense area of winds at Ireland/UK spawned from the remnants of.... Ophelia. I don't think this storm would be called such nor as intense, but clearly Ophelia has an issue with Ireland/UK 

[Josh Rubio]

2 hours ago, northwestsnow said:

Strong signal for temps to be above average across Europe from now to week 6 which will be the first week of November.

 

 

Yuck. Wet, unsettled and potentially stormy with SWly’s by any chance? Knowing our luck I wouldn’t be surprised…

[Rain All Night]

Ouchie...

[Mcconnor8]

30 minutes ago, RainAllNight said:

Ouchie...

GFS also says Ouchie

[Norrance]

Guys too many iff topic posts being made and  removed. Please remember that this is the model thread.

[Porto]

12z GFS still holding onto this storm heading in next Wednesday, definitely something to keep an eye on as soon-to-be Ophelia generates just off the US east coast which this storm spawns from