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Please ensure that the majority of your posts in this thread are model related - a theme of model discussion needs to run throughout.
Some off topic chat and reactions are ok, but please use other, more relevant threads for entirely off-topic chat (such as snow reports, met office forecasts and general chat/moans about the weather or this winter).

For more no banter and just model discussion please head to the new focused model thread - this is also a great place to post (or cross post) your longer model summaries or thoughts around the models.

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For those who think the SSW was a bust take a look at this at T+3   Then look at the NW/SE jet axis over us, then look at the fact that the downwelling has been delayed but is just und

Feel I have an apology to make.  If people are wondering why this thread vanished for almost an hour, basically I went ahead a locked the thread first. Then, went and hid it. Was feeling fed

Leaked express headline for tomorrow.   #sorrynotsorry

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Just now, Mapantz said:

Even before I became a mod, this North, South, East and West divide when it comes to snow really got on my goat, and it still does! I'll clamp down hard on any more posts using it as an excuse to snipe at others.
I'm not singling out anybody, this goes for everyone.

We have an exciting week coming up, and there's prospects across much of the British Isles, so why all this petiness? Let's keep it friendly and look forward to what unfolds.

Thanks.

?

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17 minutes ago, Tim Bland said:

18z JMA re Tuesdays low - Consistent with earlier run 

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Yes loving the JMA, its only the old GFS that has it so far further south, even the Arpege 12z had it further north. A very snowy run indeed.

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2 minutes ago, snowray said:

Yes loving the JMA, its only the old GFS that has it so far further south, even the Arpege 12z had it further north. A very snowy run indeed.

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JMA's modelling of the uppers certainly makes it snowy and the track of the low is perfect for much of the south. It would be good to see a JMA chart at 72h verify!

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3 minutes ago, Catacol said:

I agree. It has been a winter of scraps - and in this scenario better therefore than some... but this cyclonic NW is not the ideal flow for a proper winter spell. Much too marginal and generally very damp. We still desperately need some kind of blocking as has been signposted by signals and experts all winter long. I challenged a couple of US experts on twitter recently and got a confident response of impending -NAO. I hope so. I look at the current GWO orbit, the progress of the MJO, the progression of the SSW downwell - and if a block doesn't develop we will have been both horrendously unlucky but also guilty of not quite reading these signals correctly. For me Feb 2019 is more than just an opportunity for a good winter month - it is a pretty significant moment in the development of weather understanding because if it doesn't progress as expected everyone from the MetO to the best minds will be head scratching (no matter what reasons might follow in the post-match analysis...…) and there will be some big lessons learned.

Being optimistic it is Jan 26 and we have these signals in place. Plenty of time. I'm probably guilty of getting a bit too frustrated by the scrappy winter so far, but down here in Somerset I think we've had about 5 or 6 frosts in total all winter long and that is genuinely a surprise.

Good ol post(er) this one!

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Interestingly some of the ensemble members keep the low well to the South on Thursday or don't develop it at all, there wasn't many on the 12z ens so maybe the UKMO is ahead of the curve?

Tomorrow continues to look interesting, the GFS parallel keeps the east a slight bit colder meaning precipitation later in the day falls as snow.

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Maybe a surprise on the cards tomorrow?

Tuesday's low a bit further south on a lot of ens but that is very subject to change.

If we stay entrenched in the cold air then it may go on for a while, just look at P8 for example.

PS, why are so many people angry on here this evening? It's only weather, we can't control it.

Edited by Quicksilver1989
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A lot of posters claim the ECM to be the current top dog of the models and when checking the verification stats it does indeed mostly come out on top..... Now the BBC have switched from METO to ECM their forecast is now poor apparently!........What????

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5 hours ago, MattStoke said:

Random fact but OK ?‍♂️

No, people say Wales and the Midlands without realising that that won’t mean yhe entire country. e.g “major event for wales and the midlands” well, no actually.  Completely different between Penarth/Barry at southernmost tip amd Llandudno at northern most.  

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4 minutes ago, NoTraction said:

A lot of posters claim the ECM to be the current top dog of the models and when checking the verification stats it does indeed mostly come out on top..... Now the BBC have switched from METO to ECM their forecast is now poor apparently!........What????

ECM has the best verification stats on average for the entire globe; nobody can be sure on its verification for our part of the world. Also the ECM hasn't performed particularly great this winter either especially regarding the last fortnight or so.

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Still some very mixed outcomes and on the ensembles, and barely any runs agree with each other, so still plenty of time for big changes.

Also worth noting that both the lows are uncertain. More runs are now doing less with the 2nd low and taking it south more. I think that may end up being the trend to watch

 I think UKMO is close to where I think the 1st low will land.

However the big caveat is the fact that we still have probably 24hrs before we have the main low pressures forming. At this point there should be better agreement. So tomorrow is the day IMO

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(Over recent output from various models) Russian / Siberian High starts backing west at 120 hours, providing a proxy block through Europe on the Canadian vortex attack across the Atlantic. Low pressure "sink"; substantial but regionally marginal opportunities for the white stuff.

Link-ups to its NW (Scandi) via Arctic High Pressure gain in amplitude over repeated bursts.

I know things keep getting put back but I agree with those seeing a mid Feb finale for this season.

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35 minutes ago, Catacol said:

I agree. It has been a winter of scraps - and in this scenario better therefore than some... but this cyclonic NW is not the ideal flow for a proper winter spell. Much too marginal and generally very damp. We still desperately need some kind of blocking as has been signposted by signals and experts all winter long. I challenged a couple of US experts on twitter recently and got a confident response of impending -NAO. I hope so. I look at the current GWO orbit, the progress of the MJO, the progression of the SSW downwell - and if a block doesn't develop we will have been both horrendously unlucky but also guilty of not quite reading these signals correctly. For me Feb 2019 is more than just an opportunity for a good winter month - it is a pretty significant moment in the development of weather understanding because if it doesn't progress as expected everyone from the MetO to the best minds will be head scratching (no matter what reasons might follow in the post-match analysis...…) and there will be some big lessons learned.

Being optimistic it is Jan 26 and we have these signals in place. Plenty of time. I'm probably guilty of getting a bit too frustrated by the scrappy winter so far, but down here in Somerset I think we've had about 5 or 6 frosts in total all winter long and that is genuinely a surprise.

Do you still think we've got a good chance of a deep cold and snowy spell much earlier than last year still? I'm starting to wonder if it might be nearly or March even again. Which would still be good if it was as good as last year. Would still prefer sooner rather than later though.

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1 minute ago, Walsall Wood Snow said:

Do you still think we've got a good chance of a deep cold and snowy spell much earlier than last year still? I'm starting to wonder if it might be nearly or March even again. Which would still be good if it was as good as last year. Would still prefer sooner rather than later though.

Early March 2018 repeat looms imho. More severe 'action' primed for mid-Feb a la 1978.

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1 hour ago, Bristle boy said:

Agreed.

Tuesday is NOT a classic channel low imho. For a "classic", ideally, there needs to be entrenched cold over a few days before, a v cold continent, a v cold UK, with easterly or NE winds. And as the Low approaches it has nowhere to go but run along the Channel as the HP to its East/NE wont budge.

A number of these factors are not present today or forecast to be, over next 2 days.

To add weight to my view (by all means challenge me) forecast temps for Amsterdam, Brussels and Paris are between 4-6c. Not really cold. So any Easterly or SE from that Low wont really have a v cold source.

Nail on the head there

Its really only a circulation of the existing not that cold air

You could describe it as a recycled returning northwesterly

A channel low(or any low) is not a snowmaker unless it's hitting air that has all the parameters for snow

Not given up on February before it's started though

Lots of excitement to come I'd imagine now that strat warm has finally reached or is about to the trop 

Or at any rate we'll at least know at last

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1 minute ago, Catacol said:

Last year was a bit special - the depth of cold on a long easterly in March was something we have not seen in a long time and I doubt it will happen again without a similar late season split vortex event.

Do we have a good chance of proper cold in February - yes. Do I think it will happen? - yes. Am I little less certain about it though than I was 3 weeks ago? - yes. Will it lead to widespread snow? - as ever that is down to small scale synoptics....but once we get cold with a continental feed in place then the sorts of systems we have arriving on our doorsteps next week turn into snowmakers without the marginality....so get the background cold in first and then worry about precipitation second. 

Sounds a pretty good call to me @Catacol

been extremely frustrating this year

its as  if you’ve got all the ingredients for the most amazing cake sitting ready and mixed but the oven just won’t work

for what it’s worth I believe feb is going to be the time we are all rewarded for our frustration 

 

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16 minutes ago, Catacol said:

Last year was a bit special - the depth of cold on a long easterly in March was something we have not seen in a long time and I doubt it will happen again without a similar late season split vortex event.

Do we have a good chance of proper cold in February - yes. Do I think it will happen? - yes. Am I little less certain about it though than I was 3 weeks ago? - yes. Will it lead to widespread snow? - as ever that is down to small scale synoptics....but once we get cold with a continental feed in place then the sorts of systems we have arriving on our doorsteps next week turn into snowmakers without the marginality....so get the background cold in first and then worry about precipitation second. 

I'm still very confident of northern blocking developing between the 5-10th of Feb, that's been my idea now for several weeks. However I am far less confident with regards as to whether the Atlantic sector is going to co-operate. Its hardly been that helpful thus far this winter afterall.

As you say I wouldn't be looking at last Feb/March as the model, that was a pretty exceptional pattern. However given the right set-up Feb can easily match anything Dec/Jan can throw, regardless of the advancing daylight hours, especially towards the back half of the month. It is called a winter month for a reason!

Also whilst I understand why you say its marginal ,this type of set-up looks to me the type that could go all the way up to -1/2C at 850hpa, although the boundary layer isn't that cold, as long as we are on the north side of any low we will be drawing air from the current cold pool already in situ at the surface. So it should be enough. The wildcard is IF the low gets further north. There maybe quite a sharp boundary between supportive temps, and wrong side of marginal!

Quicksilver1989 - I noticed that the ensembles are less confident on Thursday than they have been, and there is still plenty of time for changes. I don't think the GFS suite are handling Tuesday at all right now simply because there is good model agreement from the others for at least some LP feature in N.France/Channel, none of them are anywhere near as far south as the GFs. I wonder whether because the GFS msybe overdoing the extent of cold air further south (a common GFS flaw) that is having an impact of the location of the LP?

Of course, it may well be right, all options are very much open still.

Edited by kold weather
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12 minutes ago, kold weather said:

I'm still very confident of northern blocking developing between the 5-10th of Feb, that's been my idea now for several weeks. However I am far less confident with regards as to whether the Atlantic sector is going to co-operate. Its hardly been that helpful thus far this winter afterall.

Is that due to the reluctance of the NAO going negative?

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3 minutes ago, Richard Fisher said:

You gotta laugh!  to add to the confusion this the latest from the met office (Bristol and surrounding area)

Outlook for Tuesday to Thursday:

Becoming wet during Tuesday, with the potential for disruptive snow overnight into Wednesday. Further rain, perhaps preceded by snow, on Thursday. Overnight frost and ice is likely.

Updated: 00:35 on Sun 27 Jan 2019 GMT

Seems a fair forecast looking at latest model output. Sorry, but cant see the point you are trying to make.

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3 minutes ago, Richard Fisher said:

You gotta laugh!  to add to the confusion this the latest from the met office (Bristol and surrounding area)

Outlook for Tuesday to Thursday:

Becoming wet during Tuesday, with the potential for disruptive snow overnight into Wednesday. Further rain, perhaps preceded by snow, on Thursday. Overnight frost and ice is likely. 

Updated: 00:35 on Sun 27 Jan 2019 GMT

I think based on everything the models have come out with today, that sounds a reasonable estimate as what will happen later this week.

I think 12z suite tomorrow maybe the big one where everything falls into place. My best guess:

1: LP in channel roughly around UKMO/GFSP, maybe a little deeper though.

2: 2nd LP rough location looks ok, but weaker and the fronts not getting as far north, maybe a good event for S.Midlands, but with some front edge snow for pretty much all bar the SW.

However, I could be utterly wrong with that, and that's the joys of this set-up for sure!

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