Jump to content
Snow?
Local
Radar
Cold?
IGNORED

Model output discussion - into the last third of January


Paul

Recommended Posts

Posted
  • Location: 50/50 Greece/Germany
  • Weather Preferences: Cold winters, hot summers
  • Location: 50/50 Greece/Germany

 

EC Scenarios 12z

ps2png-worker-commands-7745797d4-xcz62-6ps2png-worker-commands-7745797d4-8x87q-6  ps2png-worker-commands-7745797d4-74bpj-6

Each scenario, defined at 500 hPa, is associated to one of 4 pre-defined large scale climatological regimes. The frame colour of each plot represents the association to the climatological regimes. Scenario with a red frame indicates that its large scale features resembles the ones represented by the blocking, blue indicates association with Positive NAO pattern, green indicates association with negative NAO and violet with the Atlantic ridge pattern.

  • Like 2
  • Thanks 2
Link to comment
Share on other sites

Posted
  • Location: Scouthead Oldham 295mASL
  • Location: Scouthead Oldham 295mASL
8 minutes ago, feb1991blizzard said:

eps extended any good?

Mean looks a bit rubbish at day 10...

Perhaps hope of a trough dropping through scandy but downstream looks poor.

Need to rid ourselves of the Iberian heights...

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Rotherhithe, 5.8M ASL
  • Location: Rotherhithe, 5.8M ASL
37 minutes ago, Tim Bland said:

Wasn’t the MJO on our side yesterday...and it was ‘day 10’ potential then...shouldn’t it be day 9 now

It’s not yet moved into favourable phases could do so later this week, and factor in a day 10 lag it’s only GFS model really which can capture it into early February not that it’s a model to depend on. The GFSp quite frequently has been looking interesting into Feb which might be explained by this forcing.

6F20FB6E-36F3-4D75-BCE9-20E8D1D4D353.thumb.png.35733437885072c0a97ae368e552efc2.png

 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: North Newbald , 139 feet asl
  • Location: North Newbald , 139 feet asl

spacer.pngECM 12 z ensemble mean

Some opportunities for snow arising from 21st ( mainly North ) until 26th ( further South perhaps ) in this Colder 5 day period coming up after the ' storm '.

Then probably an inevitable milder blip before the fun and games of early Feb.

GEFS 12z ensembles from earlier suggest that the milder blip doesn't actually last very long ( especially in the North ) 

gfs-newcastle-upon-tyne.thumb.png.957744bb513a20befb887e0a51c86954.png

  • Like 3
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.
13 minutes ago, northwestsnow said:

Mean looks a bit rubbish at day 10...

Perhaps hope of a trough dropping through scandy but downstream looks poor.

Need to rid ourselves of the Iberian heights...

Not liking this at all now, some clusters showing Euro heights as well, even some of the ens that fall off a cliff on the temperature graphs of both suites, they look transitory, no real signs of any proper Scandinavian highs, wondering now if it will be one of those flattenings but with faux cold, 30 dayer hinting of that by mid feb and GFS 12z strat charts in FI hint at it as well.

I think this period of model watching becoming boring now tbh.

Edited by feb1991blizzard
  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

That arctic high I was tracking had made it to 85N 90E by 12z today. The 60 to 84h prog positions for it are indeed near Franz Josef Land (roughly 80N and 60E). But unforunately the models generally seem to think it will then get sucked back into the Mongolian high via west Siberia, except that a small bubble high remains near the White Sea and eventually pushes into Finland and Sweden. So it may be doing something positive for cold and snow seekers anyway. And the models could be wrong, it could decide to split in a different ratio with more of it (a stronger high in other words) heading for Scandinavia. I would expect that, if it does happen at all, to come in the first week of February and the most likely time for it to impact Britain might be the second or even third weeks of February. 

At some point there was a continuous chain of high pressure from China through Mongolia, the polar regions, western Canada all the way to Utah. It would be nice to see that joined by another chain that extends your way before all is said and done. 

Just out of interest, could somebody direct me to, or post, the ten-day GFS chart for Thursday 21st 06z (so issued on 11th Jan 06z run?) I am curious to see what the GFS thought was going to happen where Cristoph is now expected to be at its strongest. We might all find that interesting, I suppose. 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: 50/50 Greece/Germany
  • Weather Preferences: Cold winters, hot summers
  • Location: 50/50 Greece/Germany
2 minutes ago, feb1991blizzard said:

Not liking this at all now, some clusters showing Euro heights as well, even some of the ens that fall off a cliff on the temperature graphs of both suites, they look transitory, no real signs of any proper Scandinavian highs, wondering now if it will be one of those flattenings but with faux cold, 30 dayer hinting of that by mid feb and GFS 12z strat charts in FI hint at it as well.

I think this period of model watching becoming boring now tbh.

+144h is still my FI mark, deterministic models struggle to give a good mid-term outlook.

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Rossland BC Canada
  • Location: Rossland BC Canada

image.thumb.png.5f94f6afc576e3b009a86ebd6b12f842.png

 

Thanks Feb91bliz, I found this ECM chart on another thread too.

Please note that this chart (for 21 Jan 12z from 11 Jan 12z) shows the considerable limitations of taking any ten day map and discussing it as anything more than a very general suggestion. This could be described as considerably underamplified.

The GFS offering (recently posted) looks slightly closer to the mark, somewhat in error to south and with less intensity but more development than ECM managed to find. 

Neither one has as strong an arctic high near 82N 70E as will likely exist (1040 mb) either. 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
30 minutes ago, Vikos said:

 

EC Scenarios 12z

ps2png-worker-commands-7745797d4-xcz62-6ps2png-worker-commands-7745797d4-8x87q-6  ps2png-worker-commands-7745797d4-74bpj-6

Each scenario, defined at 500 hPa, is associated to one of 4 pre-defined large scale climatological regimes. The frame colour of each plot represents the association to the climatological regimes. Scenario with a red frame indicates that its large scale features resembles the ones represented by the blocking, blue indicates association with Positive NAO pattern, green indicates association with negative NAO and violet with the Atlantic ridge pattern.

The problem with most of these charts is that the blocking is too far away from the UK so that the jet can run underneath, but not so far that it undercuts sufficiently to give us proper cold conditions.  It becomes not to different in direction from normal westerlies although without the momentum behind it in a vortex driven winter.  

With the exception of last winter, in which there was never a chance not no how due to the Indian Ocean Dipole, it reflects the experience of recent winters, chances in Dec, not realised, chances in early Jan, not realised, chances in late Jan, nothing spectacular on offer, which leaves Feb, albeit with the SSW still dripping down though the layers of the atmosphere.  An all too familiar position, be nice to buck the trend even if only in the last winter month.  

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
45 minutes ago, Vikos said:

 

EC Scenarios 12z

ps2png-worker-commands-7745797d4-xcz62-6ps2png-worker-commands-7745797d4-8x87q-6  ps2png-worker-commands-7745797d4-74bpj-6

Each scenario, defined at 500 hPa, is associated to one of 4 pre-defined large scale climatological regimes. The frame colour of each plot represents the association to the climatological regimes. Scenario with a red frame indicates that its large scale features resembles the ones represented by the blocking, blue indicates association with Positive NAO pattern, green indicates association with negative NAO and violet with the Atlantic ridge pattern.

Probably a stormy and wet outlook as February begins, with the jet boxed in by heights to north and south, pushing it straight at the UK. Probably very, very snowy for high ground in the north, but I'd doubt there's enough northerly injection into any of these clusters between D10 and D15 to encourage widespread snow elsewhere. Could do with a link up between heights north and south to break up the pattern, really, but doesn't appear to be on offer.

Edited by Man Without Beard
  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Kirkburton, Huddersfield - 162.5mtrs asl.
  • Weather Preferences: Winter synoptics.Hot summers.
  • Location: Kirkburton, Huddersfield - 162.5mtrs asl.
35 minutes ago, northwestsnow said:

Mean looks a bit rubbish at day 10...

Perhaps hope of a trough dropping through scandy but downstream looks poor.

Need to rid ourselves of the Iberian heights...

Don't think Iberian heights will stop any cold and haven't in the past 

image.thumb.png.a39e5fdbd593c61e066f9f9d11b0bcd2.png

image.thumb.png.b0bcb425b29f7f86c480c68471080969.png

If its going to happen it will 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: sunny sunny Bournemouth
  • Weather Preferences: Winter: Bartlett style mild and benign
  • Location: sunny sunny Bournemouth

Indeed... unless the heights around Iberia shift, it's very difficult indeed to get cold air over the southern part of the UK at the very least.

Not seen a flake of snow yet this winter in these parts.., not expecting that to change any time soon.

  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
40 minutes ago, Daniel* said:

It’s not yet moved into favourable phases could do so later this week, and factor in a day 10 lag it’s only GFS model really which can capture it into early February not that it’s a model to depend on. The GFSp quite frequently has been looking interesting into Feb which might be explained by this forcing.

6F20FB6E-36F3-4D75-BCE9-20E8D1D4D353.thumb.png.35733437885072c0a97ae368e552efc2.png

 

Must add that this Scandi High keeps popping up from time to time. Would require a sizeable turnaround from overall ensemble guidance though. Always possible beyond D10!

Link to comment
Share on other sites

Posted
  • Location: Wantage, Oxon
  • Weather Preferences: Hot, cold!
  • Location: Wantage, Oxon
2 minutes ago, winterof79 said:

Don't think Iberian heights will stop any cold and haven't in the past 

image.thumb.png.a39e5fdbd593c61e066f9f9d11b0bcd2.png

image.thumb.png.b0bcb425b29f7f86c480c68471080969.png

If its going to happen it will 

Agree, Iberian heights are an indicator that we are not getting cold now, not an indicator for the future, if a cold evolution is to happen, they will move.  They are not a driver.  

  • Like 3
Link to comment
Share on other sites

Posted
  • Location: Drayton, Portsmouth
  • Location: Drayton, Portsmouth
2 hours ago, Tim Bland said:

Next weeks front making slower process with more leading edge snow on this run. Perhaps there’s scope for it to slow even further and dare I use the word slide?

00z Vs 12z below for 00z Weds 

DB2DF1B6-6E87-4BB0-BEC7-DC6AA9F50274.jpeg

A512F640-8E62-4F37-9E3C-B145E3E2323B.jpeg

This is the tease - we're kind of expecting it, once fronts start to disrupt on the models, they often go on to disrupt more around T120/T144 - but models still keen to push it through for now. 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: Kendray,Barnsley,God's county.
  • Weather Preferences: Snow freezing fog heatwave thunderstorm
  • Location: Kendray,Barnsley,God's county.

Hi evening all. Not great for coldies like me yet i see. Wasn't the SSW predicted to cause issues at the end of month anyway has I'm sure something was mentioned a week or so ago about N. W Europe getting alot colder then. I thinking this is what could happen now to be fair. I don't trust the gfs past say maybe 90hrs now as I'm sure this deep low is causing problems going forward also the mild in my thoughts will most likely disappear in a few more runs etc. Last night's gfs18z was the first to show something colder later on in the month. So my forecast is for an easterly/North easterly to show up in the next 3/4 days. With such a strange deep low/ssw/mjo etc the models are now hitting default Atlantic pattern as a safe bet. The colder weather is coming and I'm pretty confident. Stay safe night all. 

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: Kendray,Barnsley,God's county.
  • Weather Preferences: Snow freezing fog heatwave thunderstorm
  • Location: Kendray,Barnsley,God's county.
3 minutes ago, Man Without Beard said:

This is the tease - we're kind of expecting it, once fronts start to disrupt on the models, they often go on to disrupt more around T120/T144 - but models still keen to push it through for now. 

Getting confused so go default Atlantic driven. The mild is not certain for me at all

Link to comment
Share on other sites

Posted
  • Location: STEVENAGE, HERTS (100M ASL)
  • Location: STEVENAGE, HERTS (100M ASL)
10 minutes ago, Uncle_Barty said:

Indeed... unless the heights around Iberia shift, it's very difficult indeed to get cold air over the southern part of the UK at the very least.

Not seen a flake of snow yet this winter in these parts.., not expecting that to change any time soon.

Did you move to Bournemouth for the Snow? .  Jokes aside there is a chance of some for you this weekend whichever model you look at 

  • Like 1
Link to comment
Share on other sites

Posted
  • Location: South Essex
  • Location: South Essex
4 minutes ago, winterof79 said:

Don't think Iberian heights will stop any cold and haven't in the past 

image.thumb.png.a39e5fdbd593c61e066f9f9d11b0bcd2.png

image.thumb.png.b0bcb425b29f7f86c480c68471080969.png

If its going to happen it will 

Whilst high pressure sits over Spain its almost impossible to get genuine cold weather into the southern half of the UK. A short-lived sideswipe of PM air in the lee of a low that is rapidly swept away to our east is about the best you will ever see from that set up. The heights over Iberia are an absolute winter killer. That's not to say they might not get shifted in time but until that happens its game over.  

Usual progression from here is that they ridge north into a UK high over time or a bowling ball high in the Mid Atlantic. If I were in the Greek forum I'd be thinking Feb prospects look decent, but for us much less so.

To be clear, things may well change for the better, but there is little or no convincing evidence for that at present IMHO.     

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Posted
  • Location: Napton on the Hill Warwickshire 500ft
  • Weather Preferences: Snow and heatwave
  • Location: Napton on the Hill Warwickshire 500ft

Lets see how the GFS 12z has performed last week. Not too bad

12  Jan showing 19 Jan GFS 12 Jan showing 19 Jan.png

13 Jan showing 19 JanGFS 13 Jan showing 19 Jan.png

14 Jan showing 19 JanGFS 14 Jan showing 19 Jan.png

15 Jan showing 19 JanGFS 15 Jan showing 19 Jan.png

17 Jan showing 19 JanGFS 17 Jan showing 19 Jan.png

18 Jan showing 19 Jan GFS 18 Jan showing 19 Jan.png

19 Jan showing 19 Jan GFS 19 show 19 Jan.png

Edited by stewfox
  • Like 2
Link to comment
Share on other sites

Posted
  • Location: sunny sunny Bournemouth
  • Weather Preferences: Winter: Bartlett style mild and benign
  • Location: sunny sunny Bournemouth
11 minutes ago, Tim Bland said:

Did you move to Bournemouth for the Snow? .  Jokes aside there is a chance of some for you this weekend whichever model you look at 

I don't actually enjoy cold weather at all. Give me a nice fat Bartlett and a blowtorch SW'ly all winter long so far as I'm concerned. A big freeze always interesting from a weather POV of course.

As for snow this weekend... looks very likely to be the wrong side of marginal down here, except well inland.

  • Like 2
Link to comment
Share on other sites

Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

image.thumb.png.69cc04c17a301d98a31bb4d945363c9d.pngimage.thumb.png.ab71584185ba59cca8125f63f69d6bf9.pngimage.thumb.png.701a1fee5f16f3b726e3546186f3bd33.png  

I think it's no coincidence that where ECM keeps nosing ridges of high pressure down from near Greenland in between the two main troughs is right beneath where it has the peak residual warm anomalies in the lower stratosphere following the recent split.

What has to be resolved is how much the Atlantic trough is able to push past that line of resistance.

Physically, it makes sense that the trough struggles to retain a continuous circulation, with secondary circulations developing on its eastern flank and breaking away to 'feed' the trough over Europe. Something GFS has historically had a harder time with than ECM & UKMO.

Just how much struggle there is has a big impact on the balance of power between the two troughs.

This stratospheric influence has already played its hand for Monday in most modelling, slowing the trough arrival. Will this trend continue? I wish I could say a resounding yes but the uncertainty surrounding the La Nina standing wave and to what extent the MJO starts to oppose that are preventing any confident conclusions.

Which way it goes will also be important for how we begin February. If the Euro trough is strengthened as per the ECM 12z on day 10, westward cold air transport on its northern flank will raise the probability of the Atlantic trough being further disrupted with lows sliding toward central Europe. We've seen GFS(P) explore that outcome a fair bit - if we do go down that route, I'll be impressed at its improved coffee-smelling capability.

Conversely, the Atlantic trough powering right on in would pump a lot of warmth across western Europe, promoting an exceptionally strong (by geopotential height) Iberian-focused high that we'd then need to see shifted west in order to regain snowy weather chances any time soon. GFS demonstrated that scenario in explicit detail this afternoon.

  • Like 7
Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...