Model output discussion - late November

[Cheshire Freeze]

3 minutes ago, Mike Poole said:

But for an objective view of your performance over the last 5 years (I know you rate objectivity) you would also have to include predictions made about summer too - and they are also a matter of forum record...2018 the first that springs to mind. 

Yes, summer a lot trickier to pin down. What I do remember of that summer though is forecasting the breakdown

I'm not writing off winter this year- it would be stupid to do so at this point and I do believe we'll have chances as the winter goes on. It's just disappointing that it doesn't look to be shaping up as a classic- more galling after the fail of last year.

[SMU]

10 minutes ago, CreweCold said:

Completely agree Nick. 

People rightly slate the seasonals but when it comes to zonal, they are excellent at forecasting it as a zonal forecast requires less model skill (as zonal is pretty much climatological default

You keep going on about zonal > its such a sweeping statement because it infers that its all mild.

Within the ECM today there are 8 days out of 10 blocked & 2 days mobility east of the meridian > Therefor the weather isnt on the whole zonal.

[Cheshire Freeze]

7 minutes ago, Steve Murr said:

You keep going on about zonal > its such a sweeping statement because it infers that its all mild.

Within the ECM today there are 8 days out of 10 blocked & 2 days mobility east of the meridian > Therefor the weather isnt on the whole zonal.

Well you're being slightly pedantic as zonal refers to a general W-E movement. We're drier at the moment due to HP dominance BUT the jet is riding around the top of the HP which is gradually sinking. 

So, even though we might not be mild, the jet is moving W-E over the top of the HP going forward in time. 

If it suits you more, I can refer to the +NAO instead, which might be a better measure...the upshot is the same.

Whichever way you slice it, this is zonal/ +NAO -

Edited December 1, 2019 by CreweCold

[feb1991blizzard]

31 minutes ago, Steve Murr said:

You keep going on about zonal > its such a sweeping statement because it infers that its all mild.

Within the ECM today there are 8 days out of 10 blocked & 2 days mobility east of the meridian > Therefor the weather isnt on the whole zonal.

Steve i have to agree with Aaron over this, it is zonal but zonal with some potential, i see diving troughs into Europe further into Dec occurring rather than a pure Westerly month,, cool or possibly cold zonal but probably not any proper blocking, i always look even when there is buckling in the flow at the actual pace that low and high pressures are travelling W to East, it isn't a stationary wavelength pattern even if it has potential to deliver transient Northerlies, i actually think the general prognosis is decent for the rest of winter as the usual 'type' of zonality at this time of year isn't forthwith, in other words it does look promising but if this was Dec 2011, this wouldn't get one salivating at the mouth (yet).

[MATTWOLVES 3]

2 hours ago, Don said:

I see the upbeat mood of yesterday has been brought back down today!

I can't understand people's emotions Don, I mean, the models flip more than dolphin in shallow water. I think Damianslaw made a good point with how fickle the models seem on a sunday. There are some decent 6z ens to! And quite a few showing some deep cold to the NE. P5 Was a stunner, bringing a - 12c South. I'm not going to cherry pick one ensemble member, but I feel the general trend is for a warm up, followed by a cool down. Temps never really much above average. Oh, and still some positive signs from exeter for the months end!! I think it's perhaps best we view this winter with a very open mind. Xmas is stressful enough, without getting hung up over every single operational run. Onwards and upwards good man. 

Edited December 1, 2019 by Mattwolves

[johnholmes]

Re is the flow zonal, here is the Wilkipedia definition, you may agree or disagree, I think it is about right, but we probably are best to agree to disagree perhaps rather than risk getting into discussions/arguments

Zonal and meridional - Wikipedia

EN.WIKIPEDIA.ORG

 

[SMU]

6 minutes ago, feb1991blizzard said:

Steve i have to agree with Aaron over this, it is zonal but zonal with some potential, i see diving troughs into Europe further into Dec occurring rather than a pure Westerly month,, cool or possibly cold zonal but probably not any proper blocking, i always look even when there is buckling in the flow at the actual pace that low and high pressures are travelling W to East, it isn't a stationary wavelength pattern even if it has potential to deliver transient Northerlies, i actually think the general prognosis is decent for the rest of winter as the usual 'type' of zonality at this time of year isn't forthwith, in other words it does look promising but if this was Dec 2011, this wouldn't get one salivating at the mouth (yet).

We need to probably define form zonal as its to broad here when the main definition is strong west to east flow

Anyway the emphasis here relating to the word zonal was that its not going to be cold where as I would disagree.

ICON continues its move to the ECM with a small wedge ahead of the low now around 156 ( these features will aways get smoothed out on the seasonals )

12z first

Edited December 1, 2019 by Steve Murr

[Mike Poole]

Well the ICON finishes it's 12z run, and this doesn't look a bit zonal, for those who are pushing that agenda, T180:

[feb1991blizzard]

10 minutes ago, johnholmes said:

Re is the flow zonal, here is the Wilkipedia definition, you may agree or disagree, I think it is about right, but we probably are best to agree to disagree perhaps rather than risk getting into discussions/arguments

Zonal and meridional - Wikipedia

EN.WIKIPEDIA.ORG

 

I stand corrected then John, does that mean that PM North Westerlies don't count as it has to be west to East?

[Mike Poole]

4 minutes ago, feb1991blizzard said:

I stand corrected then John, does that mean that PM North Westerlies don't count as it has to be west to East?

Or east to west, I know it doesn't happen often!

Seriously, though, the weather, steered by the jet stream has a zonal and meridional component, almost always.  Personally I think on here some people misuse the word zonal and the non-word zonality, as a surrogate for Atlantic dominated weather.  

Anyway, at the moment, and for some long time now, there is a considerable meridional component to the jet in the NH.

Edited December 1, 2019 by Mike Poole

[That ECM]

5 minutes ago, Mike Poole said:

Or east to west, I know it doesn't happen often!

I want zonal all of a sudden

[knocker]

Meridional becoming zonal

[Methuselah]

31 minutes ago, feb1991blizzard said:

I stand corrected then John, does that mean that PM North Westerlies don't count as it has to be west to East?

I think you've highlighted a problem with idealised situations, in general, feb: there's a lot of wiggle-room between classic 'zonality' and perfect 'meridionality'...? How's about 'technically (should they ever cross the nth parallel?) meridional' east-north-easterlies? And, so much for 'zonal south-westerlies'!

I think I prefer the colloquial usage!

Edited December 1, 2019 by Ed Stone

[SMU]

Very good set of 12z runs UKMO / ICON phasing up nicely with the ECM & GFS limping along but slowly coming closer as well

 

[Mike Poole]

4 minutes ago, Steve Murr said:

Very good set of 12z runs UKMO / ICON phasing up nicely with the ECM & GFS limping along but slowly coming closer as well

 

Are you seeing the future, Steve, ECM isn't out until 6!! But GFS looking quite meridional (to coin a phrase) at T186:

Edited December 1, 2019 by Mike Poole

[SMU]

2 minutes ago, Mike Poole said:

Are you seeing the future, Steve, ECM isn't out until 6!! But GFS looking quite meridional (to coin a phrase) at T186:

I wish >> ECM 00z

[knocker]

Keeping a wary eye on next weekend with some rapid cyclogenisis going on out west

[booferking]

More blocky less zonally the 12z so far all in the right spots keep the trends going please.

Edited December 1, 2019 by booferking

[markw2680]

8 minutes ago, Mike Poole said:

Are you seeing the future, Steve, ECM isn't out until 6!! But GFS looking quite meridional (to coin a phrase) at T186:

Wouldn’t take a lot for the Azores high to be slightly over egged and drop sw a little more which could bring that nice deeper blue west and a pretty decent northerly imo. I’d be very surprised if there wasn’t changes to come in the next few days hopefully for the better for cold

[johnholmes]

49 minutes ago, feb1991blizzard said:

I stand corrected then John, does that mean that PM North Westerlies don't count as it has to be west to East?

I honestly don't know f. I reckon provided none of us get up tight about anyone elses' use then we should be fine. Maybe say something like

'general w'ly Atlantic flow but mainly Pm air or if it is predicted milder than average mention Tm air from time to time'?

[BLAST FROM THE PAST]

53 minutes ago, FiftyShadesofSnow said:

Getting boring now...I want cold, snow, till end of June same as next person...However Dec is looking +Nao whatever synoptic you throw up...the Tpv is going to generate a strong jet, and fall where we don't want it...Looking forward to Xmas onwards, the first two thirds of Dec are pretty simple normal for this time of year in Uk...This is def a Winter of backloaded optimism...Ps the Icon is a follower not a leader...

So 21 days ahead are nailed on? What model goes that far?

RE Zonal, pM air with wedges chucked in bring some nice surprises.  The word zonal ‘normally’ makes many think of Bartlett and continued long fetch SW’lies.....we aren’t stuck with them.

 

BFTP

[Mike Poole]

9 minutes ago, markw2680 said:

Wouldn’t take a lot for the Azores high to be slightly over egged and drop sw a little more which could bring that nice deeper blue west and a pretty decent northerly imo. I’d be very surprised if there wasn’t changes to come in the next few days hopefully for the better for cold

Yes, I agree.  It's a long way out so subject to change, will be interested in ECM take at same time.  It is my view that, since summer, all models have had a bias against actual amplification, which becomes important beyond the reliable day 5, due to failing to capture the solar minimum effects adequately.   

Edited December 1, 2019 by Mike Poole

[blizzard81]

Ha ha ha. Anybody else think the gfs is struggling? 

[blizzard81]

3 hours ago, feb1991blizzard said:

Yes - remember the Norwegian shortwave last year, GFS - 138 hours screaming Easterly bust.

I remember countless shortwaves over the years unfortunately

 

[BLAST FROM THE PAST]

8 minutes ago, blizzard81 said:

Ha ha ha. Anybody else think the gfs is struggling? 

Nope, displaced PV and timing of peak energy bringing disruptive storm (gales and rain or gales and snow) on target.....

 BFTP