Model output discussion - 21st Jan Onwards

[TEITS]

Certainly more interest since I lasted posted. A few points from me though.

1.  Considering its the UKMO/GEM/ECM Vs GFS then it's a no brainer to side with the Euros.

2. im rather dubious of the 0Z ECM and the difference between this and the UKMO with regards to the LP in the Atlantic. At this stage I would side with the UKMO.

3. Still uncertain how far S the cold air will dig if you compare the ECM Det with the ensemble mean.

4. How long will this colder spell last.

My answer at this stage to the above is a colder spell lasting around 4 days with more W parts prone to snowfall rather than E parts due to the N flow having a W,ly element to it. This could change and probably will in future outputs.

[offerman]

11 minutes ago, Ravelin said:

So what do we have for early hours of Monday....

ECM has a well developed low to our NW, but separation between the remnant low heights over Greenland.

UKMO also has that separation  but a less well developed low.

GFS 0Z has less well developed low and no separation

GFS 6Z just rolling out has a well developed low and no separation

The conclusion....the models don't have a clue? I know I certainly don't!

 

Best post of the Year!!!

Shows diagrams, then the last sentence is the best part, as its the truth and no one has a fathom as to what will happen. Most accurate has been I.F with his 1-2 month ahead  general weather pattern prediction (over the last few winters),(lets hope that continues with his Mid Feb Atlantic blocking prediction) but even he struggles as does everyone else with very short term Cold/snow predictions/forecasts as does everyone. In those situations now-cast seems only options.

[mb018538]

6z seems to be coming round to the ECM pattern....but quickly flattens out and goes back to a rocket powered jet, with everything flat as a pancake. Could we be seeing another split in the models? GFS v ECM/UKMO again?

[The Weather Dragon]

GFS say no - discard GFS - all eyes on ECM & in particular METO over the next few days 

[Frosty.]

Plenty of polar maritime on the Gfs 6z with the coldest shots across the north bringing snow at times and occasional frosts for all of us mixed with milder, wet and windy spells. I'm hoping the euro's are right because they show a proper cold spell next week!

[terrier]

18 minutes ago, Jonathan Evans said:

GFS say no - discard GFS - all eyes on ECM & in particular METO over the next few days 

Don't think we can discard the gfs at all in my opinion. It was a lot closer than the euros on the last cold spell a few weeks ago. The euros kept wanting to put us in the freezer yet the gfs was showing a short lived colder spell. Which the gfs came up trumps on that occasion. Not saying it will this time but think  we need to see model consistency from the big 3 first. And until that time think to discard the gfs output would be foolish. 

[BarnetBlizzard]

The GFS and its ensembles seem to be particularity aggressive with these lows attacking from the West. Is this often the case with the GFS?

If so, maybe it will backtrack a little to the UKMO and ECM, and maybe allow heights to rise to our West, rather than just our south west.  

[Singularity]

Bloomin' 'eck that was a big negative spike in the dM/dt yesterday.

So, GEFS mean goes to phase 0 in 5 days time, which means no real signal either way, and then just hangs out there for the foreseeable - so no help with amplification of the U.S. and Atlantic pattern when we could do with it.

It's a stalemate between the El Nino (Pacific) and La Nina (Indonesia) type forcing from the tropics.

I have a feeling ECM and UKMO aren't dropping the AAM as much in the next 5 days which is why we're seeing less momentum from the west days 5-6. Based on known GEFS bias I'd expect some shift of the model toward ECM/UKMO but not necessarily the whole way there.

By around 7 days from now is when we may see the MJO kick things into gear again, taking the GWO out of phase 0. That's the major difference between the longer-range signals from the Euros (and GEM, which is nice) compared to GFS, which still makes relatively little of that potential.

[karlos1983]

The GFS backtrack has already started, so if the Euro's continue to stick to the theme of the 00z output, in my opinion the GFS is only going to go one way, and it involves legs and a tail. 7 days ago the theme was clear, westerlies to dominate for a time, and interest to become very much for things to change as we move into February, which is starting to evolve now.  I'm not saying we are going to be drenched in -10 Uppers and snow up to our knees, but change is  potentially afoot.

[BLAST FROM THE PAST]

A very good ECM and looking very plausible in its theme to me.  Again thumbs up from me, and like I say I don't anticipate that we need to wait until mid or second half of Feb for winter to hit us, with northerlies the south can miss out, but certainly will be delayed in getting more wintry theme compared to NI , Scotland and NW parts. However I think like the ECM shows it holds the set up for very cold air to flood the whole UK.  Timing not too bad.  Count me in on this as game on!!, could be a decent cold episode as it will be in a disturbed set up.  

BFTP

[Frosty.]

7 minutes ago, BLAST FROM THE PAST said:

A very good ECM and looking very plausible in its theme to me.  Again thumbs up from me, and like I say I don't anticipate that we need to wait until mid or second half of Feb for winter to hit us, with northerlies the south can miss out, but certainly will be delayed in getting more wintry theme compared to NI , Scotland and NW parts. However I think like the ECM shows it holds the set up for very cold air to flood the whole UK.  Timing not too bad.  Count me in on this as game on!!, could be a decent cold episode as it will be in a disturbed set up.  

BFTP

I echo what Fred says, I feel it's game on for a wintry spell next week and I'm pleased to see the met office are continuing to mention a mid Atlantic ridge further into feb which would lead to more prolonged arctic outbreaks from the NW & N...so signs are promising for February to be easily the best month of this winter for coldies!

[Frank Trough]

1 minute ago, Frosty. said:

I echo what Fred says, I feel it's game on for a wintry spell next week and I'm pleased to see the met office are continuing to mention a mid Atlantic ridge further into feb which would lead to more prolonged arctic outbreaks from the NW & N...so signs are promising for February to be easily the best month of this winter for coldies!

I don't think it's anywhere near game on. It's a watching brief. Cross model agreement of cold air flooding south at t+96 is game on. Until then sensible money is on something more amplified than the GFS but less promising than the Euros.

[Rocheydub]

1 hour ago, terrier said:

Don't think we can discard the gfs at all in my opinion. It was a lot closer than the euros on the last cold spell a few weeks ago. The euros kept wanting to put us in the freezer yet the gfs was showing a short lived colder spell. Which the gfs came up trumps on that occasion. Not saying it will this time but think  we need to see model consistency from the big 3 first. And until that time think to discard the gfs output would be foolish. 

Spot on. You cannot discard any of the big 3 or 4, just because it doesn't show what we want it to!

[Frosty.]

3 minutes ago, Certain kind of fool said:

I don't think it's anywhere near game on. It's a watching brief. Cross model agreement of cold air flooding south at t+96 is game on. Until then sensible money is on something more amplified than the GFS but less promising than the Euros.

Its game on for the north, Scotland looks quite wintry at times and if the ecm 12z sticks to the 00z theme then cold air will flood south to all areas next week...The power of positive thinking

[Abyss]

4 minutes ago, Rocheydub said:

Spot on. You cannot discard any of the big 3 or 4, just because it doesn't show what we want it to!

Agree but when it's 1vs the rest it more than likely will be wrong

[The Weather Dragon]

42 minutes ago, -Bomber- said:

Agree but when it's 1vs the rest it more than likely will be wrong

Spot on !

[Midlands Ice Age]

3 hours ago, Ravelin said:

 

 

The conclusion....the models don't have a clue? I know I certainly don't!

 

Dont post on here much, but I agree with the above comments.

I would love the ECM to be correct....

BUT ..

It is incredibly difficult in terms of timing.

1) The Arctic high holds itself and angle towards Greenland intact.

2) The separation of the lows occurs at the correct point in the cycle to allow the AH to creep up to meet its Arctic cousin.

3) This low then  moves ESE across the UK at such a speed as to allow the high to build to the west.

Love it to happen. But we need luck on our side.

MIA

 

[Rocheydub]

52 minutes ago, -Bomber- said:

Agree but when it's 1vs the rest it more than likely will be wrong

 

9 minutes ago, Jonathan Evans said:

Spot on !

Well, look at the UKMO about 3 weeks ago. That is a perfect example of one run out on it's own, and it was SPOT ON! My point is, you simply cannot discard it, just because you don't like what it shows. It's foolish in the extreme and shows a complete lack of experience viewing the models.

[coldcomfort]

58 minutes ago, Frosty. said:

Its game on for the north, Scotland looks quite wintry at times and if the ecm 12z sticks to the 00z theme then cold air will flood south to all areas next week...The power of positive thinking

How about the power of rational thinking?  Kind of makes more sense to me and lessens the likelihood of further significant disappointments, IF as is often the case at this range things don't quite go to plan.

Edited January 27, 2016 by coldcomfort

[winterof79]

So here is our worst case scenario with numerous plunges of cold bringing wintry precipitation at times out to 360z

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=66&mode=2

 

Hopefully that will have changed to colder come the 12zs

Edited January 27, 2016 by winterof79

[Abyss]

16 minutes ago, Rocheydub said:

 

Well, look at the UKMO about 3 weeks ago. That is a perfect example of one run out on it's own, and it was SPOT ON! My point is, you simply cannot discard it, just because you don't like what it shows. It's foolish in the extreme and shows a complete lack of experience viewing the models.

I said I agreed with you so don't understand your post but one model Vs the rest is more likely to be wrong and that is FACT. Would be foolish to think otherwise

[Rocheydub]

32 minutes ago, Jonathan Evans said:

Spot on !

It was more in comment to this Bomber. Yes, it's most likely, but to discard it completely is where I have the issue, as the other contributor said.

[Nouska]

2 hours ago, Certain kind of fool said:

I don't think it's anywhere near game on. It's a watching brief. Cross model agreement of cold air flooding south at t+96 is game on. Until then sensible money is on something more amplified than the GFS but less promising than the Euros.

Agreed.

It is a large outlier for Reading   .... 

If we saw that on the GFS we would be sceptical. Probably responding to its modelled MJO phasing but even at that, it is at the extreme end of the scale. It won't be the first time long range outliers have verified - caution needed for a day or two.

Edit :-   hmmm ... maybe back to the drawing board.  

Edited January 27, 2016 by Nouska

[Eskimo]

Wow, the ECM completely surprised me this morning. Massive swing for cold, possibly prolonged as well. 

[BLAST FROM THE PAST]

This isn't the first run of ECM showing this and folk need to remember sometimes it's the 'outlier' that starts the ball rolling.  It isn't showing monstrous blocking and it is plausible I think.  Also, I think the GFS 06z although a little yo yo, isn't a bad run.  A very good mix in there if you ask me.  

Also correct it isn't game on for Bournemouth, it will remain as rain and average temps at best down there.....for now. 

 

BFTP

Edited January 27, 2016 by BLAST FROM THE PAST