Model output discussion - 21st Jan Onwards

[Mair Snaw]

12 minutes ago, fergieweather said:

I've seen no hype from UKMO over all this, however. The idea of an SSW into Feb has been consistently suggested ever since their first 3-monthly forecasts started outlining winter prospects back in the late autumn/early winter. The notion this would bring profoundly cold weather has never been touted, but instead a view of greater incidence of cold weather later in the season. Where things stand currently in the UKMO forecast thinking is that:

• There is a Sudden Stratospheric Warming beginning, but it is only a minor warming at present.
• The current SSW is not likely to meet the World Meteorological Organisation (WMO) criteria for a ‘major’ event in the near future.
• GloSea5 sees the net outcome from this event as a greater propensity for ridging in the central North Atlantic and an increased likelihood for the UK to sit under a broadly NW'ly (or at times N'ly) flow
• Consequently, the expectation is for drier conditions with temperatures somewhat below average after mid-month, as suggested for a while now in public forecast summaries
• The potential for any more pronounced colder weather always remains a possibility but is, of course, outside the scope of operational NWP timelines for now

The UKMO has updated it's info page on SSW's for those who want some baseline info on the phenomenon. See http://www.metoffice.gov.uk/learning/learn-about-the-weather/sudden-stratospheric-warming

Thank you Ian... during the SSW in Jan 2013 it caused the models some big problems with our friend Shannon Entropy getting a lot of airtime do the UKMO foresee anything as such with this warming...??

[nick sussex]

3 minutes ago, Ali1977 said:

Very informative of Ian F, maybe a chance for some chilly stuff but sounds like a "big freeze" is pretty much not happening - for this we really need an Easterly or NE flow anyway.

 If you get a mid Atlantic ridge then its not beyond the realms of possibility that you won't get a chance for this to topple towards Scandi.

The UKMO can only give a broad outline of the overall expected pattern.  I think given the winter so far even a decent spell of colder temps with some snow would be welcome by those in here who have missed out so far.

In terms of a big freeze I think to hope this late on for something Dec 2010 style is unlikely but a period of cold and snow still has a chance.

[winterof79]

9 minutes ago, nick sussex said:

 If you get a mid Atlantic ridge then its not beyond the realms of possibility that you won't get a chance for this to topple towards Scandi.

The UKMO can only give a broad outline of the overall expected pattern.  I think given the winter so far even a decent spell of colder temps with some snow would be welcome by those in here who have missed out so far.

In terms of a big freeze I think to hope this late on for something Dec 2010 style is unlikely but a period of cold and snow still has a chance.

Hi Nick,wasn't the 2010 freeze end Nov early December though?Not when you'd expect entrenched cold.

March 2013 shows that you can't discount anything during the period December to April

 

Nice ECM 120z ready to pounce

 

Edited January 28, 2016 by winterof79

[Abyss]

30 minutes ago, Ali1977 said:

Very informative of Ian F, maybe a chance for some chilly stuff but sounds like a "big freeze" is pretty much not happening - for this we really need an Easterly or NE flow anyway.

But didn't the big freeze in 2010 come from a Northerly. The second cold snap of the month

Edited January 28, 2016 by -Bomber-

[chris55]

somethings afoot i tell you...that's quite an unusual chart to be honest.

Operations have been playing with many solutions into Feb and beyond.

Ill hold fire on making any solid judgements for now. Though colder conditions before mid Feb don't look out of the question.

Edited January 28, 2016 by chris55

[nick sussex]

Not a bad ECM T144hrs output, we really need to see that big storm in the USA engage that PV lobe in ne Canada at T168hrs.

We need some good trough disruption at that timeframe to keep the UK in the cold.

[chris55]

ECM 168 not great tbh. However the longer range could show something better as the NH profile doesnt look to bad overall..

 

Edited January 28, 2016 by chris55

[Jason M]

At 168 ECM is coming into alignment with GFS. 

http://www.meteociel.fr/modeles/ecmwf.php?ech=168&mode=1&map=0&type=0&archive=0

No great shock really.

 

[booferking]

So there we have it GFS looks to be right again and the ECM was leading us up the garden path for 2 days.  GFS has been winning the cold episodes this winter so far in my eyes.  

 

This weekend looks colder than next week to be honest going by the charts

Edited January 28, 2016 by booferking

[Long haul to mild]

4 minutes ago, booferking said:

So there we have it GFS looks to be right again and the ECM was leading us up the garden path for 2 days.  GFS has been winning the cold episodes this winter so far in my eyes.  

While that may be turn out to be true this time, the GFS was appalling in the recent cold snap, continually bringing Atlantic mildness in a whole week before it actually happened.

I think it is a bit early to be calling victories for any of the models yet, even though it now looks like ECM was over amplifying with its runs yesterday.

[Daniel*]

Not going the way of GFS at 192.

[Mucka]

ECM all over the place past mid range frankly. Now stormy, hale and thunder up North?

 

JMA is a pretty good run this evening though, more so up North and interesting end.

Edited January 28, 2016 by Mucka

[Paul White.]

Might be a few wintry showers in this chart if it verifies maybe! ECM 216 hrs could be a bit breezy 

Edited January 28, 2016 by Paul White.
Not enough info about the chart

[The Weather Dragon]

Well into the 1st week of February and still no solid signal for anything significantly colder. We seem to be clutching at straws. Time is well and truly running out for this dire winter - especially for us southern/south westerners 

[bobbydog]

if anyone needs any fence or roof repairs done- give me a shout...

[Frosty.]

The Ecm 12z looks good for colder air to sweep south once the trough over the UK pushes further to the NE so beyond day 10 would be turning more wintry...in my opinion!

[Jason M]

The ECM 240 looks a respectable chart at face value but the 850 profile over north and northwest europe highlights the problems.

 http://www.meteociel.fr/modeles/ecmwf.php?ech=240&mode=0&map=0&type=0&archive=0

Its a long way to anything notable from that chart. The ECM 240 is very much in line with many of the GEFS (as is the 850 profile). 

On the positive side the Iberian high heights don't look as strong as a few days ago, but the whole set up is far to mobile for any deep cold to establish (IMO of course!). 

[Long haul to mild]

5 minutes ago, bobbydog said:

if anyone needs any fence or roof repairs done- give me a shout...

Interesting chart! Appreciate it is FI but what would it mean for the overall outlook when a PV lobe sets up shop over Britain? Would that lead to something better for cold prospects?

Edited January 28, 2016 by Long haul to mild

[Captain Shortwave]

So we can summarise the colder spells as being three phases, phase 1

This weekend

      

A chilly weekend, 5-7C in the south, low single figures in the north. Showers could be wintry almost anywhere to be honest. There should be a widespread frost Saturday night.

 

Phase 2, the middle of next week.

ECM/GFS/UKMO day 6

            

To be honest, this is looking like a less cold version of this coming weekend with no real amplification to allow the cold air to establish itself.

 

So what about phase 3

ECM/GFS/GEM

          

This holds the most interest to me, as we see all the models agree on lowering heights through Europe, now if we can get enough amplification in the Atlantic then there is a chance to drag some potent and unstable air from the north/north east. It is also worth noting that the Arctic high is never too far away and it could still have an impact further down the line.

One thing I will say is notice how each attack slowly pushes the jet further and further south so by day 9/10 it is blowing through Iberia as opposed to the UK at the moment. We really need to see a decent Atlantic ridge form though to turn the UK cold as opposed to just wet.

 

Edited January 28, 2016 by Captain Shortwave

[Duane S.]

17 minutes ago, booferking said:

So there we have it GFS looks to be right again and the ECM was leading us up the garden path for 2 days.  GFS has been winning the cold episodes this winter so far in my eyes.  

Sorry, whilst your statement that the ECM has moved towards the GFS holds some truth, the only thing leading people up garden paths is the rest of your text. No, the GFS has been woeful at the best of times this winter, specifically during the onset of the early Jan cold spell. The ECM almost certainly will be proved to have over amplified things from its promising output of the past day or two but that should be no reason to give any sort of kudos to the GFS. 

[chris55]

I just noticed that the ECM at 144 develops that little runner, with the Azores high squashed south. Doesn't really ramp it up, and both GFS and UKMO handle things differently, However I'd keep an eye on this over the next few runs as if this beefs up a bit (like yesterdays ECM runs) then it'll be a better progression re the Atlantic slider (or not)

 

 

 

[bobbydog]

4 minutes ago, Long haul to mild said:

Interesting chart! What does it mean for the overall outlook when a PV lobe sets up shop over Britain? WIll that lead to something better for cold prospects?

captain shortwave's post explains it very well ^^

[Long haul to mild]

1 minute ago, bobbydog said:

captain shortwave's post explains it very well ^^

Indeed it does ; a very timely post!

Phase 3 would seem to hold far more interest, with the Azores High firmly pushed away to the south west.

[phil nw.]

Rain and gales with some snowfall over mainly n.elevations continue to be the main theme through the model runs again this evening.

The Greenland vortex continues to run the show with it's partner in crime the Azores high to our south.

We do see attempts from time to time of cold trying to come south at the rear of the passing Atlantic lows but this is restricted by the mainly flat Atlantic jet with the next push north of milder air from the south west always seemingly waiting in the wings.

A glance at the latest fax's show the general idea of this setup

cold air coming south on Saturday 

being pushed back north Sunday

and this seems the general theme ongoing.

Parts of the north,particularly  Scotland with any height could do quite well for lying snow over the next week or so but away from those sort of locations the wait for a more widespread snowy spell goes on.

 

[booferking]

12 minutes ago, s4lancia said:

Sorry, whilst your statement that the ECM has moved towards the GFS holds some truth, the only thing leading people up garden paths is the rest of your text. No, the GFS has been woeful at the best of times this winter, specifically during the onset of the early Jan cold spell. The ECM almost certainly will be proved to have over amplified things from its promising output of the past day or two but that should be no reason to give any sort of kudos to the GFS. 

Yea but we are getting the bigger picture here ECM was going for a 5 day cold spell out to 240hr just last night and GFS 1 day maybe 2 at the most who is right in your eyes if the charts verify as they are.