Model Output Discussion - Spring Has Sprung

[Eagle Eye]

As the AAM rises, the motion derived from it also rises so I've used the forward motion rebound deviation to show the AAM rebound, this won't show distribution but it's important for showing the AAM contributions and is much more real time than the CFS updates which seem to occur randomly and the GFS updates are only daily. However, we can't really derive a forecast from this but it shows how sharp the rising AAM has been over the last few days as the tendency is such a steep gradient. Will be important for built-up momentum if we do get that mid-Feb phase 7 response (lag probably mid-Feb).

[Battleground Snow]

  @feb1991blizzard

Yep we'll take that after the 00z output 

[AO-]

2 hours ago, northwestsnow said:

What happened to a  Nino / eQbo back loaded  winter?  this one is getting worse the closer we get to Feb

The question rises for me: what about the favourable phase 6 and El Nino and the subsequent lag time? How is this picked up by the models or is it even picked up at all? I'm wondering, since we have entered phase six, so it should be visible, given the lag time of about 10 days-two weeks. 

[Dennis]

  @bluearmy hi you can ask simonlee to this

Edited January 26 by Dennis

[Met4Cast]

HUGE momentum surge coming out of the tropics at the moment with a large +EAMT event leading to a rather intense Pacific jet extension, the result of this is a very above average USA. In terms of the UK - Atlantic ridging seems favoured week 2 of Feb. High latitude blocking remains elusive however, still not convinced we're going to see prolonged deep cold on the back of this.

[bluearmy]

Nice to see gfs pull one from the top shelf 

no doubt we’ll wait another few days to see something similar 

have to say that I’m a bit surprised not to see a few more eps members end week 2 showing wintry charts 

also end week 2 beginning to see the upper spv tilting towards the pole (as an Asian warming begins to show and out some pressure on it ). This could play out like the last cycle where it rotates on this side of the pole, stretches and then potentially splits if we see a trop Atlantic  ridge punch upwards 

[bluearmy]

  @Dennis

I don’t think it’s worth it dennis 

we can see the gefs members so able to make our own analysis - and able to see that there is no Greenland ridging thus far apart from a possible transient mid Atlantic ridge headed east   

 

[bluearmy]

Uodated MJO from yesterdays runs is a little more promising 

either getting a bit stuck in the area where 6 meets 7 or going into 7 at reasonable amplitude 

of course this becomes complex where the phases meet and also the month rolls over. You’d need to be looking at quite a few phase/month composites to make an approx judgement of any kind. 

[sebastiaan1973]

The control joins the party and moves the trop. polar vortex to the east. 

[Dennis]

lets see the MJO event to what outcomes on charts will be 

part2

 

Edited January 26 by Dennis

[February1978]

  @sebastiaan1973  Party? More like a wake for winters past at the moment...! 

At least we get to dry out for a bit

[BarnetBlizzard]

  @bluearmy  Where can you see the latest MJO forecast early? I keep waiting for this page to update: 

CPC - Climate Weather Linkage: Madden - Julian Oscillation

WWW.CPC.NCEP.NOAA.GOV

 But doesn't normally update till around 2pm

[Rain All Night]

15 hours ago, RainAllNight said:

12z deterministic runs, Fri 26th to Thu 1st

The GEM again takes a different path, but still ends up at the same destination for the UK: high pressure tucking us in from the south.

12z ensemble means, Fri 26th to Thu 8th

We could see some brief interest from the northwest around 3rd/4th Feb, by the looks of it. Right at the end there, it looks like the Atlantic trough might begin to flatten up, making our winds more westerly than southwesterly, and the ECM might even be said to be looking rather stormy again by day 14.

0z deterministic runs, Fri 26th to Fri 2nd

GEM continues its streak of maverick runs, this time sending some of the high pressure west into the Atlantic. On all the other models it's looking mostly settled down south, apart from possibly Monday/Tuesday. Would be interested to hear comments from anyone more knowledgeable about sunshine prospects?

0z ensemble means, Fri 26th to Fri 9th

GEM wants to offer us some interest from the northwest around 3rd/4th Feb, but its two bigger brothers are not keen.

Edited January 26 by RainAllNight

[Anthony Burden]

Morning all,GFS at last brings in the Greenland block which we have all been waiting for still in fantasy island but a start let’s hope the theme continues,will need to study the ensembles to see if the operational has not gone on walk about.

[Tamara]

Grateful to be immune to mood swings over the (emotionless) depictions of computer models. Enjoyment and great interest is derived from seeing how the diagnostic processes related to the atmospheric circulation play out in real time. Admittedly lucky for sure, related to where I live, to be fully indulged by a remarkable (record breaking) spell of weather down here in Portugal, but that doesn't detract from being immersed in February outcomes, whatever they may be, and are two quite separate and different things.

What is unfolding at the moment is a huge drive of planetary rossby waves. Amplitude intra-seasonal tropical convection (propagating across the tropics and to head right through the Pacific), which the velocity potential anomalies identify much better than the RMM plots.....

 

.....which has already triggered precursor gravity waves (explained the other day) and primed a very substantial +ve EAMT event to in turn imply a reconfiguring of the zonal wind anomalies within the stratosphere heading through February.

That much can be said with reasonable confidence. And to be blunt, it is all that should matter at the moment based on the timescales involved. My guess is that these tropospheric drivers are vigorous enough to overcome the strength of the SPV and, as a minimum, result in a de-coupling, if not major SSW (quite conceivable). But again, that is subject to watching the evolution over the timescales involved

A whole process measured over a few weeks at a time. Staring at a computer screen every 3 to 6 hours 24/7 is not going to provide the instant gratification that this thread persistently seeks.  It is a pity b/c there is so much going on right now both in respect of current weather patterns and, looking ahead, what is being programmed within the atmospheric circulation itself.

 

[bluearmy]

  @BarnetBlizzard that’s the one 

most charts on there now from 25th 

[LRD]

4 minutes ago, Tamara said:

It is a pity b/c there is so much going on right now both in respect of current weather patterns and, looking ahead, what is being programmed within the atmospheric circulation itself.

Indeed - I'm fascinated by how warm it could get next week. I don't want to see it but it's interesting nonetheless

[feb1991blizzard]

  @Tamara

Was that a thinly veiled 'we could be in business final third of Feb'?

[Paul]

4 minutes ago, feb1991blizzard said:

Was that a thinly veiled 'we could be in business final third of Feb'?

I think it was more a 'there's plenty to keep an eye on', but if you want answers now, or in 6 hours, or 6 hours after that (and so on), then you're going to be disappointed! 

My read of what's going on right now is that it's a slow burn, the pieces are in the air, but we'll have to wait to see where exactly they land. 

And meantime, there are indeed lots of other points of interest to keep us entertained.

 

[Dennis]

Good weekend to everyone

ill not post here for a few days 

 

[Mcconnor8]

  @Dennis

Yes the Control has a blizzard in the South East lol, at least we are starting to see promising charts in FI so there is some hope now.

[Lukesluckybunch]

Control looking epic..late on in the run!

[IDO]

The op --v-- the mean in FI:

That is one BIG outlier!

Looking at the ensemble members, zero support outside the control:

I wonder what made the op go on a wild journey...?

[Battleground Snow]

  @BarnetBlizzard generally they update the plots around 12:45.

A big difference between the ec BC and non BC today.

Gfs converging somewhat.

 

[feb1991blizzard]

  @Battleground Snow

looks to me like getting a shift on into phase 8 would do the trick, huge blocking potential there.