Model Output Discussion - heading into April

[Don]

8 minutes ago, Allseasons-si said:

The control is a peach at day ten 

If only day 10 would become day 0.5!  Will happen one day.....

[JeffC]

3 hours ago, feb1991blizzard said:

GFS 18z is a stonker.

Looks like the grim reaper paying a visit!

[ItNeverSnowsInWindsor]

It’s good to see heights dropping in the Mediterranean on the UKMO t144 to allow a more potent Northerly developing  by next weekend. Let’s see where the overnight GFS and ECM runs take us beyond t144!

 

Edited March 26, 2020 by prolongedSnowLover

[SLEETY]

UKMO is the best of the bunch now at t144 ,the others not as good especially gfs which seems to be flaffing about all over the place as usual.

[MildCarlilse]

9 hours ago, snowspotter said:

Without posting loads of charts I have to say the eastward progression of the high pressure placement , shunting the cold air for weekend east of us is quite frankly entirely predictable. Just obvious really . After many a year watching the models they are still totally useless in these situations . You have to seriously question the credibility of the GFS however many upgrades it has had . When was the last time closer to the time the high pressure moved more favourably towards Greenland ? 

Agreed but they adjust at 24hrs out,however my concern is why long-fetch Northerlies are no more.

[mushymanrob]

32 minutes ago, MildCarlilse said:

Agreed but they adjust at 24hrs out,however my concern is why long-fetch Northerlies are no more.

Because the high pressure is holding ground instead of retrogressing. The cold plunge gets deflected into western Europe.

[Methuselah]

Hopefully, the GFS 00Z is pointing the way towards some springtime plumescence? Even more hopefully, even the actual weather might be headed in the right direction, too!

    

Edited March 26, 2020 by General Cluster

[Mark Bayley]

54 minutes ago, mushymanrob said:

Because the high pressure is holding ground instead of retrogressing. The cold plunge gets deflected into western Europe.

And good riddance! Much prefer for something a little warmer as we head into April (especially as we are stuck in our houses!), which the GFS suggests towards the end of the run. ECM looks like it would deliver something similar

Edited March 26, 2020 by Mark Bayley

[snowray]

1 hour ago, MildCarlilse said:

Agreed but they adjust at 24hrs out,however my concern is why long-fetch Northerlies are no more.

Them little shortwaves that develop in the flow seem to always deflect things east from what I can tell.

[knocker]

2 hours ago, mushymanrob said:

Because the high pressure is holding ground instead of retrogressing. The cold plunge gets deflected into western Europe.

Precisely/ And there is still a lot of energy running around the northern flank of the high cell/ridge associated with fluctuations within the tpv/ Where, and when,this ducks south east introducing colder air into Europe is pretty much on a knife edge which is why giving too much credence to anything post day six of the outputs is not advisable

Edited March 26, 2020 by knocker

[SLEETY]

Only a 12 c difference in temp from 6 hours ago on the gfs at the  same timescale.

 

I think they should cap this model at t144 as any output beyond that timeframe is utterly waste of taime

[Pennine Ten Foot Drifts]

1 hour ago, Mark Bayley said:

And good riddance! Much prefer for something a little warmer as we head into April (especially as we are stuck in our houses!), which the GFS suggests towards the end of the run. ECM looks like it would deliver something similar

Exactly Mark, models looking much more favourable for settled and warmer weather, which is great for those of us stuck at home with one eye on our gardens and the other on our deckchairs

[mushymanrob]

With the strat winds expected to strengthen again in the next 5 days, how will this impact on the trop? will it add energy into the trop? will that cause disruption to the building high/ridge to our west?..

 

[Methuselah]

Could April 3 turn out to be the critical point? 

April 3:      

April 4:      

April 5:      

And then pretty warm and benign right out to Day 16!

                 

[lassie23]

I'm having a self isolation BBQ on the 5th of April to keep my spirits up so hopefully it will be warm and sunny, although the only thing left in the shop was one corn on the cob.

Edited March 26, 2020 by lassie23

[Zak M]

@General Cluster  And look at these temps on the day before day 16!

Because it's before day 16, it has a 100% chance of verifying... right? 

Edited March 26, 2020 by Zak M

[SLEETY]

Gfs was a mild run from the pack and the mildest of all the runs at certain times,and at least  a 15 c diferrence in temperature from the  all ensembles run ,so it’s obviously got this Northerly sorted then.

 

What a fantastic computer weather model

Edited March 26, 2020 by SLEETY

[winterof79]

8 minutes ago, SLEETY said:

Gfs was a mild run from the pack and the mildest of all the runs at certain times,and at least  a 15 c diferrence in temperature from the  all ensembles run ,so it’s obviously got this Northerly sorted then.

 

What a fantastic computer weather model

Exactly Sleety

At 192 it runs totally against the Ensemble set developing yet another imaginary feature in the Atlantic

[knocker]

35 minutes ago, winterof79 said:

Exactly Sleety

At 192 it runs totally against the Ensemble set developing yet another imaginary feature in the Atlantic

 

But it  is not an imaginary feature. It is an upper trough that has broken away from the main lobe of the tpv which curtails westward movement of the high and initiates amplification further east. It will almost certainly not repeat this but emphasizes once again the danger of looking too far ahead at the moment

[knocker]

2 hours ago, knocker said:

But it  is not an imaginary feature. It is an upper trough that has broken away from the main lobe of the tpv which curtails westward movement of the high and initiates amplification further east. It will almost certainly not repeat this but emphasizes once again the danger of looking too far ahead at the moment

Same time this evening. The evolution starts differing from around t132

 

Edited March 26, 2020 by knocker

[Zak M]

The latest GFS run shows a high dominating the UK from day 10 onwards. 

Obviously it is far away so it's not to be taken literally, but hopefully @lassie23 is able to enjoy his barbecue without any disruption!

Also liking the looks of these temperatures:

[Methuselah]

And the GFS 12Z still shows a noticeable, if delayed, warm-up...But not before an official Net-Weather Snow-Grain Warning needs urgently-issued, for Sunday!!!

                 

After that, things will hopefully improve?

April 4:      

April 6:      

April 8:      

April 11:    

Keep on the sunny side, always on the sunny side; always on the sunny side of life...?

 

[SLEETY]

ECM looked like a big Northerly was going to develop at 168 hours onwards instead  2 days later  we get a Southerly developing.Comical modelling again.

Edited March 26, 2020 by SLEETY

[MildCarlilse]

10 hours ago, mushymanrob said:

Because the high pressure is holding ground instead of retrogressing. The cold plunge gets deflected into western Europe.

Yes Mushy,we know what is happening but as I asked,why? 

[stodge]

8 hours ago, mushymanrob said:

With the strat winds expected to strengthen again in the next 5 days, how will this impact on the trop? will it add energy into the trop? will that cause disruption to the building high/ridge to our west?..

 

I think this tells us all we need to know about the evolution going forward.

The current strong warming has only taken the zonal winds back to where they should be from the record-breaking levels we saw earlier this month.

I thought (or hoped) the warming might have been enough to initiate the final breakdown of the PV but that was unrealistic given how strong the PV has been all season and as we know most warmings, after the initial dislocation, are followed by a re-strengthening of the vortex and this is going to happen this time so from zonal wins speeds of about average we'll see a new strengthening to the mid 30s by the end of the month. This will scupper both an E'ly after this weekend and a N'ly and allow the Atlantic to fire up for early April.

The re-strengthening of the vortex at this time of year is in the nature of a dead cat bounce and it begins another sharp fall away in April but remains still well above average with reversal unlikely before mid month and more likely in the last week of the month (though some members keep positive wind speeds into May). It's a sharper decline than usual which may have some impacts - we often see northern blocking in early May along with the famous Buchan cold spell.  

I'm also noting the reversal may be stronger than average which may or may not be significant - I don't know. 

I suspect those hoping for a N'ly or E'ly in April are going to be disappointed with a more Atlantic profile than seemed likely a few days ago but early May may yet produce a late chill, we'll see.