Model Output Discussion - Into February

[Rob 79812010]

21 minutes ago, Nick F said:

It was extremely cold, coldest Feb since 1947 I think, was some snow in the east initially but west was mostly dry, 23 days of cold easterly winds, remember the big icicles and ponds / lakes frozen solid. 

Yes and even colder than Feb 63! Amazing! My dad remembers working outside in 47!

[feb1991blizzard]

14 minutes ago, Nick F said:

It was extremely cold, coldest Feb since 1947 I think, was some snow in the east initially but west was mostly dry, 23 days of cold easterly winds, remember the big icicles and ponds / lakes frozen solid. 

i think why i remember it fondly because it followed on from an almighty dumping of snow in late Jan (8-10 inches i think)

[MATTWOLVES 3]

I spy with my little eye something beginning with C....I think a colder set of mogreps ens from the 0z run...its clear to see any milder spell is not necessarily set to bed in!

Last night on channel 5 we had the documentary covering the 2018 BFTE..

I've a feeling there will be a sting in the tail of this Winter..we've already had 2 cold snaps,and most things come in 3s....so they tell me.

Let the hunt commence me lovelies.

Edited January 31, 2023 by MATT TATTOO

[mushymanrob]

1 hour ago, Rob 79812010 said:

I'm 58. Please let me know any snowy easterlies I've missed that came over pennines. Do remember a good one in 96 I think!

When i quoted you i said "i presume you mean locally" ..... i have no idea how West of the pennines fared, but i do remember cold snowy spells that hit the Country, being 66.

[Stravaiger]

1 hour ago, nick sussex said:

The GFS shows what happens if the PV doesn’t elongate and edge further nw.

You can’t sustain the high in a favourable position .

So whilst it’s true you can have an angry PV initially you need energy to disrupt under the block .

 

Nick - do you find energy disrupts south less readily nowadays than it used to?

Always seems torturous to get the PFJ to dive south of England, when it must have done all the time in winters past.

[Gowon]

19 minutes ago, johncam said:

Where is it very cold ?

Outside.... in the future ( supposing the GFS is correct)

[Rob 79812010]

37 minutes ago, mushymanrob said:

When i quoted you i said "i presume you mean locally" ..... i have no idea how West of the pennines fared, but i do remember cold snowy spells that hit 

 West of pennines never the best for Easterly snow but has happened from time to time. 

[warrenb]

Remember 1986 Feb very well. Freezing with temps around -2 to 0c for days and days but Gin clear blue skies.

[Cold Winter Night]

Very interesting times in model output land.
There is cross model agreement that these potential Euro-Scandinavian heights will be located at a higher latitude than foreseen just a couple of days ago.

Compare the EPS clusters from last Saturday's 0z to today's 0z for Friday, February 10 (then Day13, now Day 10):
Positive height anomalies are located further North and Northeast now, and the trough into Eastern Europe has 'curved back' much more to form Low heights in SE-Europe.

These new developments may make it difficult for coldies to contain their enthusiasm, this thread is alive again, but do keep in mind that at this moment the very cold runs and ensemble members we get to see do not represent the majority yet.

A good sign is the wind direction chart for De Bilt, where the South winds that were associated with a High at lower latitude have been replaced by NE/E/SE winds, due to the higher latitude of the High. They now build an ensemble majority around Day 10:

The deepest cold, bringing ice days to Holland does not convincingly make it this far West yet; the Op is clearly one of the coldest on the De Bilt T2m plume:

The mean around Feb 6/7 is down 5 degrees from just 3 days ago, so that's good.

We're heading in the right direction for cold, the Operationals are tasty, but I'd still like to see upgrades in the ensembles as well.

[Purga]

There are certainly some very cold 'possibles' in the ECM ens.

Ditto GEFS

Certainly the 2M temps look to be taking a dip.

[Rain All Night]

A collage of Tropical Tidbits 2m temperature mean anomaly charts for days 1-5, 6-10, 11-15 (from top to bottom) from the latest EPS, GEFS, GEPS (from left to right).

Edited January 31, 2023 by RainAllNight

[Ali1977]

Just now, RainAllNight said:

A collage of Tropical Tidbits 2m temperature mean anomaly charts for days 1-5, 5-10, 10-15 (from top to bottom) from the latest EPS, GEFS, GEPS (from left to right).

Eastern Europe into Ukraine most definitely heading into the freezer - Turkey Especially We need a move colder on the 12zs rather than any moves in the other direction.  Be nice to know what the METO are making of this, obviously things could very well end up as they’ve forecast of course. 

[nick sussex]

1 hour ago, Stravaiger said:

Nick - do you find energy disrupts south less readily nowadays than it used to?

Always seems torturous to get the PFJ to dive south of England, when it must have done all the time in winters past.

Good question . I think logic dictates that would be the case as the jet stream being powered up more because of GW .

And of course less northern blocking to add forcing on the jet .

[geordiekev]

3 hours ago, heath said:

Looking back the GFS 12z of 25 January was the first to show this amplification, but for 5th February, not the 6th. Just one day different. No one thought it credible, and it still may not be.

but the odds have changed substantially.

Yip, on the sherry, off on one, never gonna happen, 0% probability... were some of my favourite lines. Yet again a reminder of the cried wolf fable. Would be interesting and a learning exercise if at least 1 poster gave a reason why impossible, too much energy in Northern Arm, jet stream, etc perhaps someone brave can identify where the other models failed on this occassion.

The buckling of the jet stream tomorrow in the Atlantic seemed to be the point at which the models varied. Not knocking but always good to learn from these situations as to which model bias to put credence in.

The Arctic High, which has mostly been unfavourable for us as no HLP has been able to link up to it in the Atlantic sector, appears to have found a way further East, so defo interest ahead

[MATTWOLVES 3]

Wow...look at the 6z ens..looks like the graph of a lie detector test I took recently.. 

A colder cluster and a few hints of something much colder.

I don't care what you lot or me mother says..if we count down to another cold spell,I'm going bare back down our country lane.. you know what I mean  

Hey folks just had a thought..imagine if some of us cold lovers had to do a monthly update for the public everyday! We would be advising that we need to evacuate the Northern Hemisphere...and probably draw a line from the M4 corridor South as being in the safe zone..

Edited January 31, 2023 by MATT TATTOO

[nick sussex]

Very bizarre . There’s no support for the GFS op early stage between day 4 and 5 in the ECM ensembles. 

This is when the GFS takes the low ne and starts to eject shortwave energy se.

We’re due the ECM 06 hrs control run soon so that will be interesting to see .

[TSNWK]

14 minutes ago, nick sussex said:

Very bizarre . There’s no support for the GFS op early stage between day 4 and 5 in the ECM ensembles. 

This is when the GFS takes the low ne and starts to eject shortwave energy se.

We’re due the ECM 06 hrs control run soon so that will be interesting to see .

Forgive me for asking as im plsying catchup after getting my towel ready for lobbing We want 06z GFS op to be supported or not

[nick sussex]

Just now, TSNWK said:

Forgive me for asking as im plsying catchup after getting my towel ready for lobbing We want 06z GFS op to be supported or not

We want a clear win for either side and not a middle ground solution .

Both solutions though still need a lot to go right to deliver as we’re dealing with a Scandi high which is always traumatic !

Essentially with the GFS it drops shortwave energy se which eventually ends up over Southern Europe helping to support the high .

The Euros take a low east then more se but struggle to get enough jet cutback sw .

We’re still at the early stage here of seeing whether we at least are in the game .

[TSNWK]

1 minute ago, nick sussex said:

We want a clear win for either side and not a middle ground solution .

Both solutions though still need a lot to go right to deliver as we’re dealing with a Scandi high which is always traumatic !

Essentially with the GFS it drops shortwave energy se which eventually ends up over Southern Europe helping to support the high .

The Euros take a low east then more se but struggle to get enough jet cutback sw .

We’re still at the early stage here of seeing whether we at least are in the game .

Many thanks for such a comprehensive reply. Worthy of written response

[nick sussex]

The ECM 06 hrs control run highlights why you don’t want a solution that tries to combine the Euros and the GFS.

You either want the low southern Greenland to become quickly absorbed as it heads ne and ejecting shortwave energy cleanly se or you want that low to run east se and a decent gap to the upstream troughing .

[goosey007]

1 minute ago, nick sussex said:

The ECM 06 hrs control run highlights why you don’t want a solution that tries to combine the Euros and the GFS.

You either want the low southern Greenland to become quickly absorbed as it heads ne and ejecting shortwave energy cleanly se or you want that low to run east se and a decent gap to the upstream troughing .

wheres your money Nick ?

[nick sussex]

Just now, goosey007 said:

wheres your money Nick ?

I really wouldn’t like to say ! It’s very unusual for this type of divergence which starts at day 4 . As long as it’s one or the other we would have something to build on , a hybrid solution would make things more complicated .

[MATTWOLVES 3]

11 minutes ago, goosey007 said:

wheres your money Nick ?

I would say its firmly in his pocket being as he resides at multiple locations

[Northern Sky]

35 minutes ago, nick sussex said:

We want a clear win for either side and not a middle ground solution .

Both solutions though still need a lot to go right to deliver as we’re dealing with a Scandi high which is always traumatic !

Essentially with the GFS it drops shortwave energy se which eventually ends up over Southern Europe helping to support the high .

The Euros take a low east then more se but struggle to get enough jet cutback sw .

We’re still at the early stage here of seeing whether we at least are in the game .

Isn't it nearly always the case that when we have a model stand off with two clear options that the end result is a hybrid? 

 

[nick sussex]

3 minutes ago, MATT TATTOO said:

I would say its firmly in his pocket being as he resides at multiple locations

Very funny ! You should all be happy as since I got back from Cyprus it’s hardly rained in the UK ! 

I’m here to suffer with my fellow coldies !