Model Output Discussion - Colder but how cold and for how long?

[Rocheydub]

I for one, am encouraged going forward. I noticed it yesterday and again today and it also ties in (somewhat) with what @Tamara has been saying

If you look at the 2 below T240 charts from ECM and GFS, you will notice the draining away of low heights from Svalbard area with hints of height rises nudging in.

I will enjoy the bitter cold as it arrives tomorrow night and maybe I will see a few flakes. It's only 3 degrees today feeling a lot colder and I love that! (To each their own) but as the week draws to a close, I will be watching for hints of HP cells creeping into Scandy. I realise model fatigue is strong, but I have been fascinated watching how all this has begun to unfurl. I'm keeping the faith.

[JimBob]

2 hours ago, Froze were the Days said:

Not when it comes to an active Atlantic they're not...different otherwise!

Yes good point! 

[Rain All Night]

An overview of this morning's runs.

Deterministic runs (to day 7, Sat 20th)

I think I'll take the GEM...

T850s for Dorset (to day 8, Sun 21st)

UKMO, GFS, ECMWF - GFS is making the most of the milder interlude on Wednesday

 

Ensemble means (at day 10, Tue 23rd)

Looking windy...

[Vikos]

Seems the zonal spell will short-lived and options for ScandiHi are rising start of February…

 

[AWD]

7 minutes ago, Vikos said:

Seems the zonal spell will short-lived and options for ScandiHi are rising start of February…

 

Is that the elusive Dan Hutchings?

[Rain All Night]

8 minutes ago, Vikos said:

Seems the zonal spell will short-lived and options for ScandiHi are rising start of February…

 

How come Zonalisierung gets its own German word but Blocking doesn't?!

[Penguin16]

1 hour ago, nick sussex said:

Strat warming’s can effect where the PV goes . So yes it’s a fact . We have had instances before where a warming has shuffled up the NH pattern to the detriment of coldies .

Understood but we can’t categorically say that’s what caused it this time? 

[nick sussex]

Just now, Penguin16 said:

Understood but we can’t categorically say that’s what caused it this time? 

No but it’s the main suspect at the moment .

[Penguin16]

28 minutes ago, Vikos said:

Seems the zonal spell will short-lived and options for ScandiHi are rising start of February…

 

Must be cold there when he’s wearing a hat inside ha

[Daniel*]

It’s not a new revelation I posted EPS a week ago and I did not like the direction it was going, backing away from an extended period of cold weather, a few didn’t like it, weakening the Greenland blocking relatively quickly with strong signal for return of +NAO after 18th, ultimately it is turning out like this. This is not I told you so, just that it is really quite unusual to have EPS make a big flip even in longer range. I do not see it often.

12z EPS NAO on 6th Jan 

 

And now.. the +NAO signal has only strengthened so clearly some more mobile weather is unfortunately coming, it still could be quite cool for northern areas with hill snow. Some suggestion though of late January for NAO returning to neutral with perhaps next opportunity surfacing into early February. 

 

We also see the AO doing a similar thing…

 

In conclusion the less cold/milder weather should be temporary as we see according to Tamara’s musings and reinforced by GLOSEA, likely the best is yet to come, and that could well be in month of February (again!). Seasonal models always painted the late winter period as having the greatest shot of deep cold, and extensive high lat blocking. 

[blizzard81]

Much better on the latest ecm 06z control run. The monster lobe that comes off Canada looks more curtailed and there is decent amplification in our vicinity. Compare the new chart to the 00z one. I think this is what Tamara is telling us to look out for. 

[Battleground Snow]

4 minutes ago, blizzard81 said:

Much better on the latest ecm 06z control run. The monster lobe that comes off Canada looks more curtailed and there is decent amplification in our vicinity. Compare the new chart to the 00z one. I think this is what Tamara is telling us to look out for. 

Had a quick browse of the ensembles, and a few are hinting at height rises into scandi,

Probably will get bulldozed away by the energy to the northwest later on, but maybe something to lookout for in future runs 

[blizzard81]

Just now, Battleground Snow said:

Had a quick browse of the ensembles, and a few are hinting at height rises into scandi,

Probably will get bulldozed away by the energy to the northwest later on, but maybe something to lookout for in future runs 

I feel the next chase brewing already lol

[tight isobar]

Ec 6z- and a want of uk channel/ land mark structure!!.. again this has legs.. !! Nudge north ya @@******

Edited January 13 by tight isobar

[blizzard81]

If (it's a big if) we could get enough amplification/ridging next weekend before the PV bomb traverses the atlantic, it would be natural to assume that this lobe would start to track on a more southerly trajectory and also weaken. Hope springs eternal. Because this is still 6 days away, there is certainly time for favourable upgrades over the next couple of days. 

[SilverWolf]

18 minutes ago, tight isobar said:

Ec 6z- and a want of uk channel/ land mark structure!!.. again this has legs.. !! Nudge north ya @@******

IF this makes land and is further north, could it stall and pivot, or is big enough to just barrel through regardless? 

[Kirkcaldy Weather]

There has been good consistency from the majority of modelling with my thoughts from 8 days ago January 5th remaining steadfast, this IS a significant- Severe winter weather event 

• 850 hpa temperatures briefly 15-20 degrees below average across nearly all of the UK
• SIGNIFICANT- SEVERE ice days x multiple in succession 
• Surface temperatures also 15-20 Degrees below avg again covering large quantities of the UK and Ireland

 

"At the moment we're looking at the latter stage of Jan week 2 MIDMONTH through about 5>6 days for the coldest surface and 850hpa temps"

  

This was always probable from January 15th to around the 21st 

[bradymk]

Quite a large shift north of the precip on Wednesday on the 12z icon

Edited January 13 by bradymk

[Harveyslugger]

3 minutes ago, bradymk said:

Quite a large shift north of the precip on Wednesday on the 12z icon

How large we talking

[Kasim Awan]

ICON brings in 2-5cm along the South Coast. Those south of the M4 need to watch with interest. Could be a rogue run but this potentially isn't a done deal yet. 

Edited January 13 by Kasim Awan

[Gowon]

The far south is in with a chance again.

[Johnp]

Icon 12z is massively different on this run over the Arctic.  Interesting. 

9 minutes ago, Harveyslugger said:

How large we talking

Not Pembrokeshire

[kumquat]

10 minutes ago, Harveyslugger said:

How large we talking

About 150 miles north I'd say. Paris to Brussels kind of distance which brings it back to the far south coast.

Edited January 13 by kumquat

[blizzard81]

On the back of that much improved ecm 06z control, this is a massive improvement on the latest run at day 5. Look at that difference compared to the 00z run. 

[Johnp]

Just now, blizzard81 said:

On the back of that much improved ecm 06z control, this is a massive improvement on the latest run at day 5. Look at that difference compared to the 00z run. 

Yes, the PV looks in disarray in comparison to the 00z run