Model Output Discussion - cold spell to end Autumn

[nick sussex]

1 minute ago, karlos1983 said:

Karlos likes this 

I’ve found another shortwave which complicates the ECM and results in less ridging north .

Its that small kink north east Canada at T144hrs hrs, this effects the ridge near Greenland and the phasing action of both upstream lows .

So room for improvements .

[booferking]

Much improved ECM but i would take GFS run over it any day ECM only 2 dayer.

 

 

Edited November 28, 2017 by booferking

[swfc]

At 216 hrs ecm isnt has good as this morning imo

Bit odd given the better profile at the 140 mark???

[damianslaw]

Quick one from me - trend and theme continues to be a cold one, with a temporary milder blip this weekend, just like what happened on Monday, then another northerly reload - both ECM and GFS showing this.

 

[Mucka]

JMA no deep Atlantic low either so that is 4 out of 5 models that, "don't do an ECM"

And 192, not bad, could be better. Just need the blocking a little further West

Edited November 28, 2017 by Mucka

[karlos1983]

Let’s look at 144 as our marker, fl thereafter. Great afternoon viewing. 

fantastic that mutually weather minded folk get to share this passion as the wife thinks I’m a mad man and is considering sectioning me. 

Edited November 28, 2017 by karlos1983

[tight isobar]

Yep' those dramas playing out via ec-12z..

Its a bit of a car crash @eastern most canada!. 

And the ridge starts to revert into back-wards overdrive...

Devolping into a dense HP....

However as we have alluded...post 144..

Much resolve-yet.

[knocker]

The High pressure just needs to slide neatly over the UK to ward off the evils lurking in the woodshed over Canada

Oh no

 

Edited November 28, 2017 by knocker

[nick sussex]

Heres the aforementioned subject of my irritation:

This stops better ridging into Greenland, it also then puts on its shades and relaxes in its sun lounger waiting to complicate the phasing action of the upstream lows one over the ne USA and the other further upstream.

The damn thing is still sitting there at T168hrs!

 

 

Edited November 28, 2017 by nick sussex

[gottolovethisweather]

14 minutes ago, damianslaw said:

Quick one from me - trend and theme continues to be a cold one, with a temporary milder blip this weekend, just like what happened on Monday, then another northerly reload - both ECM and GFS showing this.

 

1

The theme of late Autumn for what seemed like weeks, but in reverse as we hit Meteorological Winter.  Yes, please. Instead of cold weekends and mild rainy/showery working weeks, it's mild weekends and cold working weeks with copious amounts of...... wintry stuff, snow, sleet, cold rain for some, frosts, freezing fog and whatever Mother Nature wants to throw at the UK.  Still BLOCKED for the foreseeable.

Edited November 28, 2017 by gottolovethisweather

[Had Worse]

I think we should be looking at T+96 and no more whilst keeping our feet on the ground and prozac in the cupboard.

Yes its nice to view the stonking runs but this current situation being a complex one (more so because of the unusual hemisperic pattern) is bound to have a few hairpin bends in it.

I keep reminding myself that we have 3 months of winter up coming and then the spring can throw in a few surprises... plenty to look forward to.

[Mucka]

ECM from 72h has 5 bouts of phasing troughs - it should have less than 1% chance of verifying anywhere near by day 10. 

If ECM 00z is anything like it I will never post here again.

Oiy! Stop willing it to happen.

[I remember Atlantic 252]

Worst FI that I have seen for a long time, very bad infact

[Frosty.]

I'm just happy to see another arctic plunge next week, and not forgetting this weeks colder spell!

Here's my anti-mild highlights

The Ecm 12z is a considerable improvement on the 00z and I hope it keeps getting better and better and prolonging the potential cold next week!??

[ArHu3]

1 minute ago, Mucka said:

ECM from 72h has 5 bouts of phasing troughs - it should have less than 1% chance of verifying anywhere near by day 10. 

If ECM 00z is anything like it I will never post here again.

Oiy! Stop willing it to happen.

Let' hope so but when ecm 240h ends with almost flat zonal I take it seriously ? it has such a bias to not become zonal that when it does there probably was no other way 

[feb1991blizzard]

I have to say I prefer the GFS to the ECM, higher risk but big reward, its no good having those clean Northerlies because away from the East Coast, where is your PPN coming from, frigid uppers means the GFS has a touch about 17th Dec 2010 about it, even if the ECM hadn't toppled, I doubt a dumping would have ensued by the end of the run.

[ICE COLD]

ECM day 9 has -8 850 uppers for where I live and then on day 10 it has +5 850 uppers . So a rise of + 13 . Hopefully day 10 is well off because that chart is dirt . 

[nick sussex]

Okay I promise this is the last crayon job this evening.

Mucka just mentioned phasing and heres where this on the face of it tiny feature plays a part.

The two lows circled will phase, the shortwave develops into a low as its fed low heights this then also phases and drags the phased systems further east and tilted more unfavourably.

The shortwave also stops a bit more WAA feeding nw and also effects the tilt of the low se of Newfoundland.

So the ECM basically delivers a chain of events timed to perfection for maximum irritation and downstream effects, at this point we should ask it the Euromillions winning numbers!

The odds of this chain of events occurring on its 00hrs are minimal.

Because of this tonights ECM from T144hrs is given the first SSO (Suspicious Synoptic Outcome) award of the season.

[blizzard81]

Just now, feb1991blizzard said:

I have to say I prefer the GFS to the ECM, higher risk but big reward, its no good having those clean Northerlies because away from the East Coast, where is your PPN coming from, frigid uppers means the GFS has a touch about 17th Dec 2010 about it, even if the ECM hadn't toppled, I doubt a dumping would have ensued by the end of the run.

Very true. I agree. However, the way the ops have been behaving over the last 24 hours, we could have a completely different solution on the 00z runs. 

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

There is absolutely no certainty with weather modeling, apart from massive investment in super-theres computers simply there are no current means to accurately predict long-term. I think that last winter went strangely smoothly in terms of the longest signal range was winter 2009/2010. I think it is clear that our current core signals are not strong. With this in mind theres more liquid for what we will get and just as we have stronger rules at the time suspected 46 other names to remove some bricks. From a half-glass perspective full if the long-term models prove to be wrong then let's remember that when the weather shows so mild! In a way no idea what might happen in 10 days time is a good thing, then at least you can always hope for something good to turn up. I think it's well documented that background signals are more appropriate than last year. So with this in mind let's see what winter brings.

[The PIT]

GFS yummy ECM yucky. Luckily it's all out in la la land so anything could happen yet. Next few days will be interesting model watching.

[chris55]

12 minutes ago, nick sussex said:

Heres the aforementioned subject of my irritation:

This stops better ridging into Greenland, it also then puts on its shades and relaxes in its sun lounger waiting to complicate the phasing action of the upstream lows one over the ne USA and the other further upstream.

The damn thing is still sitting there at T168hrs!

 

 

  Is it cause or effect?

Can a shortwave 3000 miles away really have that much influence alone on the downstream pattern?? Or does the longwave synoptic forcing allow such features to grow and develop?

 

[Met4Cast]

GFS > Very good, about the best we could get synoptic wise

UKMO > Good, probably very good if it were to go out further

ECM > Good start, yucky ending. The important thing is that it's an improvement in the short term and then it does something weird upstream so post 144hrs in the bin, I think. 

Much better position than we were last night going forward. I suspect we'll see more ups and downs in the coming days but things are looking good, for now.

[JBMWeatherForever]

With all that Very Cold air only just to our north by next week, our next northerly which still looks odds on to me, is going to be a potent one and infact not unlike mid December 2010 !  The ECM should hopefully get back to a good northerly overnight. Maybe just having a moment like the GFS did earlier.   

[LRD]

12 minutes ago, chris55 said:

  Is it cause or effect?

Can a shortwave 3000 miles away really have that much influence alone on the downstream pattern?? Or does the longwave synoptic forcing allow such features to grow and develop?

 

Exactly what I was thinking Chris. It's not really a case of the shortwaves destroying anything. It would be the general long wave pattern that allows those 'little' lows to break through or over ride northern blocking. In cold winters those areas of low pressure still exist but the overall pattern is more conducive to cold so they don't mess anything up. So, if things aren't properly set up then the shortwave pattern will be allowed to develop in a way that kicks northern blocking into touch. However, to be fair, we will only know if the pattern was ever conducive by observing the behaviour of the shortwave synoptics and seeing the reality unravel! Sort of chicken and egg but it's the long wave atmopsheric pattern that's the true driver

Edited November 28, 2017 by LRD