model discussion Model output discussion 11th July onwards

[Mike Poole]

4 minutes ago, Don said:

That’s the issue with the lack of cold air to tap into.  A front loaded winter with cold rain in the south?!  No thanks, what a waste!

It is a risk, @Don, and worth highlighting now.  We’ve had the odd winter that has shown early promise (2019 springs to mind) but the polar vortex has taken control before wintry synoptics have delivered anything at all due to lack of cold air.  I know there is a regional aspect to this, early cold is more difficult to achieve in the south than the north, I totally get that.  

[damianslaw]

1 hour ago, Mike Poole said:

I know some posters on here have said normal Autumn fayre to come…but really, ECM T240 shows anything but I think:

A - you have this massive ridge from UK to beyond Siberia, @carinthian alluded to this earlier.

B - there’s no driver of unsettled weather from the US either.  

C - there’s an Arctic high.  

What little of the vortex there is still shows (probably) a broadly 5 wave pattern.  I cannot see a very unsettled autumn for the UK out of this, but it will be well into November before cold patterns emerge, and then, a front loaded winter pattern will ask the question, where is the cold air?  

Bouts of unsettled weather still possible without a zonal Atlantic flow.. right now is just about as unsettled as you can get.. and immediate horizon remains the case. A stuck pattern can see the Atlantic trough stuck over UK for long periods..  that's been the theme of 2021 switches from anticyclonic to cyclonic/trough dominated, the latter equals unsettled though perhaps not quite as much as a broad zonal flow.

[Frosty.]

There’s some very pleasant weather indicated for mid October on the Gfs 0z operational, indeed, the improvement starts during the second half of next week and this is the culmination!   ?…mid October BBQ anyone? ? …young Sidney is confused! 

 

 

[Methuselah]

Yes, Frosty, I'll take this as we go into mid-October!

    

    

    

[Frosty.]

Looking at the ECMWF 0z operational…Well, at least these charts are warm!   

Shut yo mouth frosty!  

Edited October 1, 2021 by jon snow

[carinthian]

10 hours ago, Mike Poole said:

I know some posters on here have said normal Autumn fayre to come…but really, ECM T240 shows anything but I think:

A - you have this massive ridge from UK to beyond Siberia, @carinthian alluded to this earlier.

B - there’s no driver of unsettled weather from the US either.  

C - there’s an Arctic high.  

What little of the vortex there is still shows (probably) a broadly 5 wave pattern.  I cannot see a very unsettled autumn for the UK out of this, but it will be well into November before cold patterns emerge, and then, a front loaded winter pattern will ask the question, where is the cold air?  

Yes Mike, I think mild and dry by day 10, especially for southern areas of the UK. Most models now showing a strong Euro/Asian Ridge by then.  The feeling over here is that settled conditions will be the norm for most of October, especially in Euroland. However, the Atlantic as you mention to is not in a normal behaviour mode and colder weather is anticipated as we head towards November, more than likely sourced from the NE. Lets see !

C

[mb018538]

UKMO definitely the pick of the runs this morning if you'd like something drier and warmer after a turbulent weekend and early part of next week:



 

[mb018538]

GFS ensembles also looking much drier after the next week. Pressure rising, and rainfall falling away.

[johnholmes]

Looking beyond the weekend weather with the latest 500 mb anomaly charts

Ec and a broad trough around 20-30W is the main feature with contour flow through this, quite strong over and close by the uk but almost no flow in the Iceland and Greenland areas

Noaa is not dissimilar re the trough and flow. It does show a slight +ve anomaly over nw Iberia but little ridging showing in the actual contour flow, and similar on its 8-14 chart. Perhaps features in the far west, slight ridging over the pacific and marked troughing over/just west of the Canadian/us west coast will affect our area  with time. I suspect though all that will happen is that a ‘pulse’ of troughing from this will run through the overall northern hemisphere current pattern. From th present charts I cannot see any ridging developing in the uk area/nw or ne of us within the 8-14 day period.

This implies that a disturbed spell of weather is looking the main feature, windy at times, bands of rain then showery with only fairly brief more settled spells. A probable nw-se split in the activity just mentioned.

ECMWF/GFS DAY 8-10 MEAN 500MB HEIGHT COMPARISON

WWW.METEO.PSU.EDU

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

This link to ECMWF 10+ day outlooks for 500 mb, surface and 850 mb temperatures is interesting. IF it is correct then there is no signal for any real warming showing 10-12 days ahead. In fact the 850 mb temperatures are shown to slightly decrease from the wnw?

http://www2.wetter3.de/Fax/00_ECMWF_ENS_p0_500hPa+144_240.gif

 

 

 

Edited October 1, 2021 by johnholmes

[Methuselah]

Roll on, next Friday:      

[ANYWEATHER]

The confusion from the gfs and ecm is quite apparent today in the medium term.....

[Methuselah]

Even better!      

[mb018538]

A very anticyclonic 6z run from Thursday next week....almost certainly an outlier. 

[Frosty.]

For sure there’s better news from the GEFS 6z mean from later next week onwards with more of a north-south / northwest-southeast split!… for the south / southeast  it’s a more settled extended outlook according to this but probably continuing more changeable / unsettled further north by northwest ? !  

Edited October 1, 2021 by jon snow

[Zenarcher]

A bit of a shorter update today, so here's the latest from the average weather model charts,

Saturday will start decent with some sunshine, but will quickly become wet and windy as the day progresses. Sunday will be wet and windy throughout Scotland, but drier further south with showers and a bit windy across England and Wales. Monday will be a breezy day with some sunny spells and showers as the low pressure moves away, before more rain moves in over night into Tuesday as another low pressure is on its way over the South of England and Wales, which could bring some strong winds. There's still uncertainty over it at the moment for example the ECM is predicting gusts across the South of England between 40 and 50 mph but the GFS has 20 to 30mph gusts.

   

From Wednesday to Friday next week, we'll see ex-hurricane Sam make its way up to or near Iceland and Greenland in the Atlantic, similar to what most models predicted yesterday. However, across the UK, most models agree that high pressure will build across the south, resulting in a drier and less windy spell later next week, but the north will remain unsettled.

  

Most models continue to show the South as more settled and the North as more unsettled next weekend and into the start of the following week.

  

Latest amination, 2nd Oct to the 11th (Average model outlook, click to view larger, clearer image.) 

[Frosty.]

Being a coldie, doh, yes I was frosty and now I’m Jon snow..major clue there!  cold charts are great to look at, but they don’t produce anything at this time of year away from the Scottish mountains…but, warm / settled charts do!..and for anyone hoping for a return to fine and warmer than average weather in the run up to and including around mid October and even into the second half?, these charts from the GEFS 6z should be right up your alley!  

 

Edited October 1, 2021 by jon snow

[Frosty.]

To be sure, the ICON 12z looks much better in a weeks time, to be sure!    

[Frosty.]

The Ukmo 12h morphs into something much more settled too, especially by day 6!  

 

[mb018538]

A notable shift to high pressure again this evening! This has see sawed an awful lot the last few days. Middle of next week onwards could see a change from this stormy weather. 

[Frosty.]

The Gfs 12z operational looks much more settled & pleasantly warm later next week too, for the majority!
 

 

Edited October 1, 2021 by jon snow

[LetItSnow!]

22 minutes ago, jon snow said:

The Gfs 12z operational looks much more settled & pleasantly warm later next week too, for the majority!
 

 

Pleasant days but I imagine those charts for the 8th/9th would bring mist & fog and more notably, chilly nighttime temperatures! Perfect weather for a strong display of colour on the leaves, mild days and chilly nights.

[Methuselah]

Mein Gott in Himmel, not retrogression (the dreaded R-word) at T+240!?

    

It must be the new Little Ice-Age! Better late than never?

[carinthian]

9 hours ago, carinthian said:

Yes Mike, I think mild and dry by day 10, especially for southern areas of the UK. Most models now showing a strong Euro/Asian Ridge by then.  The feeling over here is that settled conditions will be the norm for most of October, especially in Euroland. However, the Atlantic as you mention to is not in a normal behaviour mode and colder weather is anticipated as we head towards November, more than likely sourced from the NE. Lets see !

C

Evening, signs of a shift of ridging to the NW by day 10 on the latest GFS op. This is needed if we are to get any anticipated colder weather from the NE .  One run so far . Lets see how the means and European Model shape up. This is an encouraging development for coldies, I especially like how the 300mb flow chart is taking shape.

 C

[Methuselah]

Spot the difference:    

[Weather Enthusiast91]

1 hour ago, jon snow said:

The Gfs 12z operational looks much more settled & pleasantly warm later next week too, for the majority!
 

 

As long as it doesn't bring 20+ Celsius temps, and we have some cold foggy nights then I am all for it!  

I love the chilly crisp autumnal mornings/nights. 

Edited October 1, 2021 by Weather Enthusiast91