Model output discussion - 21st Jan Onwards

[northwestsnow]

2 minutes ago, Mucka said:

 

Yes only slight amd needs to keep going that way to make any real  difference.

 

UKMO also a minor improvement in that direction.

Two words spring to mind, euro high. One could see a decent northerly setting up but for that horrid block across mainland europe.

[Mucka]

Just now, northwestsnow said:

Two words spring to mind, euro high. One could see a decent northerly setting up but for that horrid block across mainland europe.

 

Yeah we have struggled all winter to displace the Azores high and lower pressure across NW Europe.

[Bristawl Si]

45 minutes ago, northwestsnow said:

Well maybe your right paul, i was under the impression GP was going for the change around the 26th of jan?

He was.

The torpedo went on 4th Jan i think. 3 weeks to impact, from that date in early Jan.

[snowray]

Cant even get a half decent Northerly toppled out of this now, just look at them uppers, joke or what?

[Ali1977]

Day 9 is full of potential on GFS

[Geordiesnow]

9 minutes ago, Mucka said:

 

Yes only slight amd needs to keep going that way to make any real  difference.

 

UKMO also a minor improvement in that direction.

 

MetO now calling Atlantic ridge end of Feb instead of just after mid month, oh well.

Then it will be beginning of March, mid March end of March and so on and so forth and to be honest, it can get quite a bit farcical when long term predictions are constantly being bought back because you are bound to be right in the end. 

That said, the fact is nobody knows and at the end of the day, its what the models show in the reliable is what REALLY counts in the end, far too often people get sucked into long range forecasts and because its something they read that they want to read and it all sounds plausible then expectations rise and more often than not ends up in dissapointment. 

Been a lot of hype about February and the impacts of SSW but again, unless you see the charts in the reliable to medium frames showing the potential rewards of SSW then there is not much to hope for really. At the moment, the charts have shown some hints of something more interesting(Especially the ECM) but we could end up something like the UKMO/GFS set up where all we really get is a quick Northerly via a half hearted(if you can even call it that!) ridge of high pressure in the mid Atlantic. 

At the moment, the REAL interesting aspects of the outputs is the the brief storm force winds tomorrow morning, the fairly potant cold shot on Saturday into Sunday which could lead to some lowland areas in the North in particular receiving falling/lying snow even and the potential for another deep low for Monday.

[snowray]

As I was saying earlier in the moan thread, you would think that some kind of Northerly was odds on but the Euro slug just barges in yet again and holds everything up so milder air gets mixed into the flow.

 

This weekend though is in fact a small upgrade, could get a few Wintry showers almost anywhere in the UK on Saturday. Some heavy snow in parts of the North I would think.

Edited January 28, 2016 by snowray

[karlos1983]

The GFS is just taking the Biscuit out of us now!! "You want cold do you UK.... have cold rain and that's your lot.."

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=222&code=0&mode=0&carte=1

Edited January 28, 2016 by karlos1983

[BarnetBlizzard]

Just now, karlos1983 said:

The GFS is just taking the Biscuit out of us now!! You want cold do you UK.... have cold rain and that's your lot..

http://www.meteociel.fr/modeles/gfse_cartes.php?ech=222&code=0&mode=0&carte=1

 

For me, that chart shows a lot of potential... 

[Geordiesnow]

1 minute ago, snowray said:

As I was saying earlier in the moan thread, you would think that some kind of Northerly was odds on but the Euro slug just barges in yet again and holds everything up so milder air gets mixed into the flow.

 

This weekend though is in fact a small upgrade, could get a few Wintry showers almost anywhere in the UK on Saturday.

Think its more down to the fact of the Iceland shortwave and the positioning of the trigger low which means the uppers ended up more diluted on the GFS 12Z run than anything to do with high pressure over Europe. As usual the GFS gets messy and the UKMO is cleaner therefore probably a bit colder but we all know the UKMO is pretty poor at picking up shortwaves so I would not bank any NW'ly next week will be a nice clean flow at this stage. 

The ironic thing is, initially the 12Z GFS was better upstream to my eyes but its kinda like, you get one thing go in your favour but another goes against you so its hard to win in the end, pretty much sums up the winter regarding cold weather unfortunately. 

[nick sussex]

I think its looking likely that the initial PV split will not deliver an extended period of cold. So we're now back to hoping that the Arctic high will build later and we don't see any PV lobes thrown westwards.

The GFS has some potential later on but we've been here before!

[karlos1983]

Just now, BarnetBlizzard said:

 

For me, that chart shows a lot of potential... 

Winter 2015/2016 summary for you in one word....

But yes, Portugal could get cold  

[Daniel*]

It feels like something has got to give eventually! 

[nick sussex]

3 minutes ago, Earnest Easterly* said:

It feels like something has got to give eventually!

That's a very unusual set up, to see a shortwave running south/se and developing in that way. The issue is the timeframe, if we were guaranteed that the PV would remain split and the Arctic high would build then I'd be a bit more optimistic but we seem to be in this pot of gold at the end of the rainbow set up! Will any of these better synoptics actually turn up and verify.

[Daniel*]

This is what is scuppering any sort of block to the west from getting a foothold. Rapid cyclogenesis.

[bobbydog]

27 minutes ago, BarnetBlizzard said:

 

For me, that chart shows a lot of potential... 

well its been a great winter here, we've had over three feet of potential. i took the kids out to build a potential-man, then we had a potential-ball fight. brilliant!

[BarnetBlizzard]

1 minute ago, bobbydog said:

well its been a great winter here, we've had over three feet of potential. i took the kids out to build a potential-man, then we had a potential-ball fight. brilliant!

Isn't that what model watching is though- looking for potential that could produce weather scenarios which appeal to you. 

[nick sussex]

There are quite a few things going on that will effect how much cold gets into the UK and also the prospects for another opportunity towards day ten.

Initially there is the question of any phasing with shortwave energy of the upstream troughing between T120 and T144hrs.

Then we have to cast our eyes to a storm that's expected to develop over the Rockies and run ene. This is now looking like another crucial development because its this storm which engages the PV lobe in ne Canada and helps to pull this further west. As this happens this helps to displace the Azores high and open a window for a shortwave low to drop se from near Greenland.

 

[winterof79]

37 minutes ago, snowray said:

As I was saying earlier in the moan thread, you would think that some kind of Northerly was odds on but the Euro slug just barges in yet again and holds everything up so milder air gets mixed into the flow.

 

This weekend though is in fact a small upgrade, could get a few Wintry showers almost anywhere in the UK on Saturday. Some heavy snow in parts of the North I would think.

So if this weekend is upgrading 2 days before I wouldn't get hung up about a northerly next Thursday 7 days away.

[bobbydog]

Just now, BarnetBlizzard said:

Isn't that what model watching is though- looking for potential that could produce weather scenarios which appeal to you. 

yes it is but the weather tends to ruin the best intentions of the models!

[Snipper]

7 minutes ago, bobbydog said:

yes it is but the weather tends to ruin the best intentions of the models!

Is that the models are suppose to do?  Pander to some people's wishes. 

[Singularity]

Better alignment of the Arctic High with a better extension through Greenland on the GFS 12z compared to previous efforts.

Unfortunately, it appears that our first attempt to get a NW-SE jet trajectory with the jet heading down into Europe will be interrupted by the fairly active Atlantic trough leaving the U.S. Even if we see enough trough disruption to halt the progress of the main trough and allow a secondary low to break away to the SE or at least extend the trough in that direction, as per the 00z ECM, it seems that we'd need some seriously strong height rises through Greenland for that to happen to the extent needed for much of the UK to benefit. I did say I had a feeling the first week of the month would cause some irritation! 

When it comes down to it though, the potential for such situations to go the right way is expected to be increasing as the month progresses, and I believe what GFS almost pulls off just beyond +240 is a good reflection of that. The key thing is getting the shift of the subtropical high westward in the 7-10 day range with the jet firing back down into Europe. Then we can worry about how strong the jet across the U.S. is... hopefully weaker than GFS keeps suggesting at the moment.

 

Yes, I'm a bit disappointed about the way it looks to pan out here next week - but this is countered by my relief to see the tropical forcing having significant impacts on the troposphere within the 5 day range, as I have been suspecting would be the case. This part was always about getting the ball rolling, but with the chance of getting a snow event out of it just to keep us on our toes. It may also be the development that GP was alluding to with his 'torpedo' analogy (the big poleward ridge via Alaska... woosh) - it's just that it's turning up 5 days beyond the limits of the range of dates he provided. Given the range of his forecast, that's not half bad! Assuming I'm correct about the torpedo, that is!

[fergieweather]

1 hour ago, Geordiesnow said:

Been a lot of hype about February and the impacts of SSW but again, unless you see the charts in the reliable to medium frames showing the potential rewards of SSW then there is not much to hope for really. 

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

[Ali1977]

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.

[weirpig]

2 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.

Yes But below average conditions  from a northerly flow  would still bring snow .  However  for me its a little to late in the season anyway.