Winter Model Discussion Thread 12Z onwards 5/1/13

[johnholmes]

The press will ignore that plus weren't they warned not to make public announcements? I'll expect a slap on a wrist for him Monday when the bosses are back in.

highly unlikely Pit, he will have been advised what to say by the senior man so only an idiot would go against what he advised. From looking at the video he commented much as Ian F has suggested the senior man feels things are this morning.

[Methuselah]

I think it's a snow goose, not a swan

Might even be a Russian Eagle - minus one head!

[TEITS]

John, I will remind you of last month when the NWP picked up on the Atlantic return and you rather rubbished my assessment because your beloved height anomalies were showing blocking. We know what happened...

The MOGREPS did not back the failed December easterly, the OPs Centre was, I believe, uncertain but favoured the EC initially before the NWP collapsed the set-up.

So for anyone wanting to back the ECM right now I would advise the strongest of caution.

Why are you assuming that the MOGREPS is supporting the 0Z GFS. When Ian F referred to this model being more mobile than the ECM that could equally refer to what the 06Z is showing at +240. A mobile pattern does not always equal mild and as the 06Z GFS shows the lobe of PV to the W of Greenland actually backs W.

P.S Please stop saying caution. We all know what can go wrong and many of us are keeping an open mind. May I suggest you do the same instead of always favouring the mild option!

[fergieweather]

The press will ignore that plus weren't they warned not to make public announcements? I'll expect a slap on a wrist for him Monday when the bosses are back in.

There was no such 'warning' and Chris will have had a full one-to-one briefing with the Chief Forecaster before going on air. Nothing he said is at odds with UKMO forecast stance.

[The Northern Ramper]

There are plenty of posts with my views and why-maybe yesterday page 20 of that model discussion No 396 explains my stance

Re the comment from Ian about 500mb charts. They did predict it but I missed it and gave a reasonably full account of this soon after it happened. No idea where on the forum it is now though.

I have seen your views John, it's fair to say I mean't Ian B, and yes you did give an account on missing it.

[Catacol]

John, I will remind you of last month when the NWP picked up on the Atlantic return and you rather rubbished my assessment because your beloved height anomalies were showing blocking. We know what happened...

The MOGREPS did not back the failed December easterly, the OPs Centre was, I believe, uncertain but favoured the EC initially before the NWP collapsed the set-up.

So for anyone wanting to back the ECM right now I would advise the strongest of caution.

Actually both MOGREPS and EC backed a blocked solution back then, but MOGREPS was the first to pick up on the atlantic pushing further through and the block receding further to the east.

However back then Ian the Strat signals were not in favour of solid High Lat blocking, and for my part I was duped by the fact that the PV was off centre. Off centre it was, but is was still very energetic with strat temps low. Residual energy over Canada was enough to push the block back - there was no support in the strat really for that block to stick over Iceland/Greenland with the overall westerly regime still very much in control. Lesson learned there for the future about the need to be cautious when the vortex is wobbling but not split.

Being objective about it (I hope) we have a very different situation now. None of the models has a very good grip of strat factors, certainly not the strong top down warming forecast at the moment, and human interpretation would suggest that there is very much more support for sustained high lat blocking this time. The vortex is set to split, perhaps into more than 2 parts over time, and the centre of the warming is right where we want it in the medium term. Crucially mean winds are reversing today... and look set to remain either reversed or very light. This will deprive the vortex of the energy it needs to reform properly, and should allow HP to remain in control. If anything the danger of HP moving too far west is the long term worry... not so much any sign of a reforming Greenland LP signal.

So - again hoping I am being objective here - I think op runs that are not clever at incorporating strat signals are likely to be playing catch up to a situation that human interpretation is best to come to grips with. A reforming vortex with sustained energy over Greenland just doesnt look possible at the moment bearing in mind the strat forecasts. If they start to change, then we can start to worry.

Edited January 6, 2013 by Catacol_Highlander

[The Northern Ramper]

There was no such 'warning' and Chris will have had a full one-to-one briefing with the Chief Forecaster before going on air. Nothing he said is at odds with UKMO forecast stance.

How often does the mogreps run Ian?

[phil nw.]

Finish any postings folks-will be closing this one shortly.

[phil nw.]

OK closing this now-new thread here.