Model Output Discussion 01/09/17

[Man With Beard]

For those desperate for an early cold snap ... the ECM ensemble clusters have a couple of teasers today. Cluster one and five in particular - both show ridging to our north.

(But it's TOO EARLY for the real stuff guys!!!)

[knocker]

Just to note before this evening's runs the 06 GEFS anomalies continued the consolidation of the retrogression of the Atlantic trough and height building to the east. This would back the upper flow and give quite pleasant conditions with temps above average in the UK, particularly in the south with the far north still liable to systems popping around the top.

Edited October 7, 2017 by knocker

[Ice Man 85]

1 hour ago, Man With Beard said:

For those desperate for an early cold snap ... the ECM ensemble clusters have a couple of teasers today. Cluster one and five in particular - both show ridging to our north.

(But it's TOO EARLY for the real stuff guys!!!)

I'll take what I can get. Yes...I'm *that* desperate.

Also does CAA stand for Cold Air Advocation or Coldies Against Azores? I can never remember.

Edited October 7, 2017 by Ice Man 85

[Singularity]

5 hours ago, Summer Sun said:

Some very pleasant temperatures on show from the 06z for later next week

Some quite impressive warmth building across W. and C. France on this run, with support from the preceding 00z plus the 00z ECM. 

If we could just get a more direct feed from the south on the day... but that's being greedy I know! As far as I'm concerned a late reminder of summer is perfectly fine in October, before my opinion steadily inverts itself as November progresses (early cold in that month rarely cuts the mustard all the way down here). 

[damianslaw]

A fairly unsettled spell ahead, but signs the azores high is likely to ridge in to kill off the worst the atlantic can throw at us, and instead we end up with rather mild damp drizzly sort of conditions, perhaps some lengthy sunny breaks in southern parts, but mostly cloudy in the north - hardly inspiring stuff, but alas we are into the second week of October.

As we enter middle of the month, signal for higher pressure more generally, perhaps a surging of the azores high which would bring some chilly conditions at night but pleasant days.

Longer term - depends on the strength of the atlantic, if fairly weak, the azores high could build further north and east and pull in a cooler continental feed with frost defiantely on the cards - hints this could occur in the Met Officer 16-30 day forecast.

Those who bemoan the azores high, sometimes its resurgence into the UK can herald a much colder period late autumn through until Spring, blocking the atlantic and quickly trangressing heights north, doesn't often happen, but some of our best cold periods in winter have started with such synoptic - Dec 2009 was a good case in point. Summer hot periods likewise often start with a surging of the azores high north over the UK.

[feb1991blizzard]

All aboard the November Northern blocking train.

[Man With Beard]

This evening's ECM looks as perfectly aligned as can be for warmth to spread up from the south next weekend - low 20s pretty likely on that, might even touch 24/25C on the east coast if absolutely everything works out. An encouraging/discouraging trend (choose your preferred adjective!)

[summer blizzard]

2 minutes ago, Man With Beard said:

This evening's ECM looks as perfectly aligned as can be for warmth to spread up from the south next weekend - low 20s pretty likely on that, might even touch 24/25C on the east coast if absolutely everything works out. An encouraging/discouraging trend (choose your preferred adjective!)

Yikes. Daily records probable on Sunday and probably Monday from tonights Euro. 

Thankfully tonight's GFS is not so eager and has a flatter flow which would prevent anything more than a smidgin above 20C. 

In the longer term its worth saying that the coming amplification is the result of significant burst of westerlies in the eastern Pacific (the first real one since June which then led to our hot spell) however as expected models do show the pattern reverting with another burst of easterlies across the central and eastern Pacific which should into the second half of the month favour a pattern more akin to that seen in Aug-Sept. 

[blizzard81]

Yep, Ecm goes for a full blown Indian summer for mid October

[knocker]

The ecm still looking at a deep low 964mb tracking south of Iceland by 00 Weds. with associated fronts already impacting the west of Scotland. These will quickly track east bringing heavy rain and westerly gales to Scotland and windy with blustery showers further south during the rest of the day. From this point the amplification mentioned in previous posts occurs resulting in the next  deep low dominating the Atlantic further west with the associated fronts just skimming NW Scotland on Friday as the high pressure pushes north Thereafter the high pressure hangs on as the troughs to the west bang on the door resulting in a light southerly drift and temps above average in the UK.

Edited October 7, 2017 by knocker

[Ice Man 85]

20 minutes ago, blizzard81 said:

Yep, Ecm goes for a full blown Indian summer for mid October

That thing has a serious death wish.

[Man With Beard]

Worth bearing in mind for coldies that a blast of warm air is no bad thing if you want to see a cold pattern set up. One main way that northern blocking gets established is when warm air gets into northern latitudes. The result is often a high setting up in that location. If it is far enough north, lows from the Atlantic may well undercut and the UK ends up on the cold side. In fact the ECM T240 shows the first signs of this happening.

[Ice Man 85]

45 minutes ago, summer blizzard said:

Yikes. Daily records probable on Sunday and probably Monday from tonights Euro. 

Thankfully tonight's GFS is not so eager and has a flatter flow which would prevent anything more than a smidgin above 20C. 

In the longer term its worth saying that the coming amplification is the result of significant burst of westerlies in the eastern Pacific (the first real one since June which then led to our hot spell) however as expected models do show the pattern reverting with another burst of easterlies across the central and eastern Pacific which should into the second half of the month favour a pattern more akin to that seen in Aug-Sept. 

All things considered, you would have to bet on that little b-word the ECM being right though. 15c 850s!. Doesn't bear thinking about.

[Ice Man 85]

7 minutes ago, Man With Beard said:

Worth bearing in mind for coldies that a blast of warm air is no bad thing if you want to see a cold pattern set up. One main way that northern blocking gets established is when warm air gets into northern latitudes. The result is often a high setting up in that location. If it is far enough north, lows from the Atlantic may well undercut and the UK ends up on the cold side. In fact the ECM T240 shows the first signs of this happening.

Would never work out that way though. its either above average muck from the azores, or having to endure rain from the atlantic to keep the temps around where they should be. Personally, I'd rather we get dry weather with temps where they should be. Sadly once again, the models prove my point that settled weather cannot come without temps rising above where they should be. Not this yea anyway.

[ANYWEATHER]

31 minutes ago, blizzard81 said:

Yep, Ecm goes for a full blown Indian summer for mid October

Yep only to be washed away in future model runs.....

[Ice Man 85]

5 minutes ago, ANYWEATHER said:

Yep only to be washed away in future model runs.....

One can only hope.

[Man With Beard]

15 minutes ago, Ice Man 85 said:

Would never work out that way though. its either above average muck from the azores, or having to endure rain from the atlantic to keep the temps around where they should be. Personally, I'd rather we get dry weather with temps where they should be. Sadly once again, the models prove my point that settled weather cannot come without temps rising above where they should be. Not this yea anyway.

I dunno Ice Man, in recent years your theory has been correct but someone higher up the page mentioned how December 2009 turned cold through a surge from the south, so never say never, I personally think there's a fair chance of it happening on this occasion.

[Newberryone]

I'm not sure, but I think judging by tonight's Ecm that nothing beyond Wed next is very certain, for this run would seem to be slightly less amplified than the previous run with the Atlantic knocking more aggressively on the door.

[Man With Beard]

6 minutes ago, Newberryone said:

I'm not sure, but I think judging by tonight's Ecm that nothing beyond Wed next is very certain, for this run would seem to be slightly less amplified than the previous run with the Atlantic knocking more aggressively on the door.

If there is a model that will over amplify, it will be the ECM, so yes I agree no way of being certain we'll get quite the mild surge it suggests. But it will take quite a bit shift for it but to be above average next weekend

[Daniel*]

Wow 17C 850mb temps to the South West point taken its 8 days away and a small blob - but that’s remarkable and possibly unprecedented ‘heat’ for the middle of October. Mid 20s I would think unsettling warm for some, it also appears the yet not remnants of Hurricane Nate will track clear NW of the U.K. into the Arctic Circle. Accompanied with 'goodies’ that are not good for our friend or foe PV the latter! This does seem to have been quite common place in recent years, vigorous depressions in the high latitudes last Winter stands out the poor ice. All makes for an interesting build to the silly season, very early days but there does look to be more room for optimism this upcoming Winter.  

 

Edited October 7, 2017 by Daniel*

[knocker]

But that 850mb temp 0nly translates to a surface temp of 19C.which of course is pretty good for this neck of the woods in October (22C in the east Midlands). The EPS means tonight are indicating the abdication of the surface high SE and veering the SW south westerly so still quite pleasant, particularly in the south.

Best remind myself that talking about specific temps 8-10 days down the road is a definite no no.

Edited October 7, 2017 by knocker

[Ice Man 85]

13 minutes ago, knocker said:

But that 850mb temp 0nly translates to a surface temp of 19C.which of course is pretty good for this neck of the woods in October (22C in the east Midlands). The EPS means tonight are indicating the abdication of the surface high SE and veering the SW south westerly so still quite pleasant, particularly in the south.

Best remind myself that talking about specific temps 8-10 days down the road is a definite no no.

Far from it, Knocker. I appreciate specifics rather than ambiguous terms like "warm" etc. Warm/cold are very subjective.

[Gael_Force]

28 minutes ago, knocker said:

But that 850mb temp 0nly translates to a surface temp of 19C.which of course is pretty good for this neck of the woods in October (22C in the east Midlands). The EPS means tonight are indicating the abdication of the surface high SE and veering the SW south westerly so still quite pleasant, particularly in the south.

Best remind myself that talking about specific temps 8-10 days down the road is a definite no no.

The US weather site that has been used on the hurricane threads has all the ECM data (free for now). 

https://weather.us/model-charts/euro/cornwall/surface-temperature-f/20171015-1800z.html

 

 

 

[knocker]

3 minutes ago, Gael_Force said:

The US weather site that has been used on the hurricane threads has all the ECM data (free for now). 

https://weather.us/model-charts/euro/cornwall/surface-temperature-f/20171015-1800z.html

 

 

 

Yes i realized that a few days ago as Ryan Maue has been plugging it a fair bit on twitter.

Edited October 7, 2017 by knocker

[Gael_Force]

2 minutes ago, knocker said:

Yes i realized that a few days ago as Ryan Maue has been plugging it a fair bit on twitter.

I saw he parted company with WB; is he involved with this site? There's a huge amount of free data including every one of the 50 ensemble runs.

 

Edited October 7, 2017 by Gael_Force