Model Output Discussion 18z 30/09/15

[Captain Shortwave]

There is a serious risk of November beginning with temperatures approaching 20C in the south given the good agreement between the GFS and UKMO.

GFS

 

Great alignment on the flow, allowing warm air to travel northwards across the UK with little mixing out of the 850s.

We will have to see how much agreement we can get on this from the ensembles and the ECM later. But certainly a trend this afternoon to bring more influence across the UK from the high to our east. 

[Summer Sun]

A very mild end to October and start of November from GFS with temperatures getting very close to 20c at times for some southern parts

 

 

Potential for 2 very mild Halloween's in a row as well

Edited October 26, 2015 by Summer Sun

[Ali1977]

GFS very different this evening from day 11 , with a big scandy ish high setting up - I'm guessing the fact it is day 11 makes it pretty unreliable and no doubt won't be there in the next run

[legritter]

GFS very different this evening from day 11 , with a big scandy ish high setting up - I'm guessing the fact it is day 11 makes it pretty unreliable and no doubt won't be there in the next run

thats whats so interesting looking at 10/11 days ahead ,Theres a reason its showing so lets keep an eye out .

bUt at that range any model i would take with a pinch of salt ,some long range chatter Met of further outlook talks of colder continental air possibly paying us a visit ,but certainly at the moment typical autumn fayre although i have not yet set eyes on tonights ECM ,cheers gang 

[knocker]

Tonight's ecm has a brief resurgence of the block mid run before moving it south and letting the Atlantic in although the south is not too bad.

http://www.tropicaltidbits.com/

 

[ANYWEATHER]

Evening all! Anyone making assumptions on tonights model output is a better man than me! The 10 day timeframe is really a laugh!  The models are toying with a Bartlett scenario at least for a while, But then again we have had all the available synoptic patterns across the Uk over recent weeks from both models ! Perhaps the reliable time frame is tomorrow!    

[knocker]

Tonight's gefs anomalies have the HP to the east realigning to a more SW/NE orientation with some ridging from the S/SW with the trough away in the western Atlantic. So nothing too odious emerging from the woodshed and it all rather depends on how the surface HP aligns. It's looking distinctly possible that the lows driving across the Atlantic will swing NE impinging on Scotland whilst the rest of the UK remain under the HP albeit with a westerly airstream. But that very much depends on the detail.

Edited October 26, 2015 by knocker

[Summer Sun]

As we move into November the ECM ens shows high pressure building across the south from mainland Europe with any rain becoming increasingly confined to the far north and west

 

Edited October 26, 2015 by Summer Sun

[knocker]

The ecm anomaly very similar to the GEFS and in the ext period looks like a swathe of HP running SW/NE taking in at least the bottom half of the UK. As always a fair bit down the road and where the surface HP ends up.

 

[Man With Beard]

There is a serious risk of November beginning with temperatures approaching 20C in the south given the good agreement between the GFS and UKMO.

GFS

 

Great alignment on the flow, allowing warm air to travel northwards across the UK with little mixing out of the 850s.

We will have to see how much agreement we can get on this from the ensembles and the ECM later. But certainly a trend this afternoon to bring more influence across the UK from the high to our east.

Good call CS, though the ECM wants to push the mildest part away from the UK by the start of October. It's interesting to see what's possible at this stage of the year (like with last year at this time), but it does require absolute perfection. Will become clearer within 48 hours.

[phil nw.]

The upcoming warmth looks to be peaking around the turn of the month as the southerly flow establishes on the western side of the Euro block.

An image showing the temperture anomalies from the ens for the 3 day period 30/10 to 1/11 from NWxtra

 

quite a wide swathe of W.Europe and Scandinavia affected during this time.

 

[bluearmy]

The upcoming warmth looks to be peaking around the turn of the month as the southerly flow establishes on the western side of the Euro block.

An image showing the temperture anomalies from the ens for the 3 day period 30/10 to 1/11 from NWxtra

viewimage.pbx.png

quite a wide swathe of W.Europe and Scandinavia affected during this time.

Coldies should be happy with an early November chart like that. All that warmth heading north!

Looking at the x model extended ens - I wouldn't be writing any obituarys for the nw European blocking just yet though a more nw/se orientation seems to be the direction of travel as has been mentioned by a few.

If it hasn't been posted earlier, the GEFSP now the GEFS

Edited October 27, 2015 by bluearmy

[knocker]

Broad overview of latest EC32

 

By the 3^rd large area of HP Eastern Europe with ridging from the south west with the trough Greenland. Temps above average.

 

By the 12^th the HP area to the east has gone but new high pressure area south of UK with a west to east orientation that brings the UK under it’s influence with a westerly flow and temps still above average.

 

A week later, the 19^th,  the  surface analysis has undertaken further adjustment with the HP to the south west  and the trough mid Atlantic playing a larger role. Still zonal but more unsettled and temps around average.

 

From then on until the 26^th, and this is very broad brush, zonality is maintained with LP to the NW and HP to the SW with a probable north/south split weather wise over the UK.

 

Summary

 

All in all not too bad with a period of temps above average but settling down to a more mundane zonal affair for the last fortnight but the weather by no means bad particularly in the south.

[knocker]

The ecm run this morning basically has the HP to the east in charge and remains so through to the end of the run. Some very pleasant temps a fair bit above average. I can just see this breaking down to zonality when we get to the nitty gritty later. Such is life

http://www.tropicaltidbits.com/

Edited October 27, 2015 by knocker

[Man With Beard]

The prospect of a warm start to November is even more evident this morning on the ECM, with an excellent gradient in the pressure lines for drawing up a southerly - 16C to 20C a possibility over this coming weekend and into next week. Longer term, on ECM it looks increasingly as if the block over Eastern Europe will win out and even reinforce. That means little trouble from Atlantic storms next week, but a tricky one to forecast temperatures, as a slight continent element will see a slow downward drift eventually (and possibly quite cold), whilst a certain positioning of the high (such as what we have this morning on ECM) would allow regular reinforcement of milder winds encroaching from the south.

[knocker]

The GEFS anomalies this morning proceed with the transition and changing orientation of the HP but keep it in close proximity to the UK which, as it happens, fits in pretty well with ops run.

 

[mb018538]

Looks like being quie warm at times! Which I don't mind at all this time of year. ECM looks especially warm and more settled than the GFS. Jet looks like staying to the north, with quite a lot of troughing over the polar regions allowing for the storm track to keep away from the UK.

It's not really deep enough into the winter season for anything properly cold anyway, but it could easily end up chilly and dank. Save the proper cold for another 6 weeks time when we have some nice cold air to tap into! For now, make the most of the mildness and chepaer heating bills!

[johnholmes]

The anomaly charts and synoptic ones mostly seem to have got the idea of an upper ridge E/SE of the UK and the main trough well out in the Atlantic. This gives overall a flow from south of west into the UK, so on the mild side most days. How unsettled is for the synoptic models to give detail.

links below

http://mp1.met.psu.edu/~fxg1/ECMWF_0z/hgtcomp.html

 

http://www.cpc.noaa.gov/products/predictions/610day/500mb.php

[Summer Sun]

UKMO this morning shows high pressure rising from the south east with rain becoming restricted to the north and northwest and mild for most areas

 

 

ECM this morning shows the high dominating from the weekend with some very mild air at first under a southerly flow

 

 

To save posting lots of charts, here's the D10 one as the high remains in charge

 

 

As the high takes over further across the UK we could see an increasing risk of frost and fog developing and maybe not quite as mild by day, but nothing extreme looks to be heading our way for quite some time

[Man With Beard]

In the absence of extreme cold prospects, we instead have extreme warmth prospects. How about this for 1st November??!

 

 

 

 

 

 

Get the BBQ back out of the shed???

 

Looks sunny for many places, light winds for England/Wales, and with the GFS maximum temperature charts in good conditions, you can sometimes add 1 or 2C to get the nationwide maximum for that day - so a shock 21C in the SE could happen.

 

The November temperature record is 21.7C - odds of this being broken??? 

[Ali1977]

The last time we had temperatures in the 20s in Nov was 1946, warm air being pumped up in a similar fashion as to what is forcast next week.  We all no what happened in the Winter following this, I know it's not linked but still an interesting thought.  Maybe this blast of warmer air will affect the NH in the next few weeks flipping the AO and NAO into a negative slide!!! (wishful thinking)

[mb018538]

I think we could squeeze a 20-point-something somewhere, but to get to nearly 22c would need something really exceptional.
Perhaps slightly less wind and 850s around 14-15c would achieve this.

Either way, it looks incredibly warm for the time of the year. The average for London for Novemeber is only 10-11c, so we're talking a good 7-9c above average here. 

Devil is in the detail, but if the high holds firm enough and the rain keeps away, it could turn into an almost summer like spell of weather for some parts. 6z GFS is pretty warm again.

[IDO]

Nice to see, after some wild runs from various models, a sort of agreement upcoming and at D10 the means for the big three are singing the same song:

 

   

 

The block remains mid-latitude to our East with the feed coming from the Azores. GEM and GFS at D16 are still showing agreement with slowly sinking heights, though in reality that may just be the effect of time and it may well be that the D10 may be closer to what we eventually see at D16; that is a continuation of Wave 4 in the NH:

 

 

 

The AO ties in with this, going positive into mid November and that would suggest a continuation of MLB rather than the HLB of the last couple of months (or so). So the Met Office early Winter forecast (Nov-Jan) of milder than average would fit in with that scenario: http://www.metoffice.gov.uk/media/pdf/c/o/A3_plots-temp-NDJ_v1.pdf

 

 

 

 

[solarcycle]

The Met Office is suggesting something cooler than average for the South East come the end of November.   I'd be interested to see what someone more knowledgeable than I thinks on how this fits into the model output.

[mountain shadow]

The Met Office is suggesting something cooler than average for the South East come the end of November.   I'd be interested to see what someone more knowledgeable than I thinks on how this fits into the model output.

Well, the end of November is outside the time range of the current day to day normal model output.

 

The GFS 18z into far FI continues to show a disrupted vortex. It is not hard to see how a colder pattern could occur if this continues.

 

http://max.nwstatic.co.uk/gfsimages/gfs.20151027/06/384/npsh500.png