Model Output Discussion - 16th Jan 12z onwards - Smile While You Post!

[Ali1977]

Tue-Thurs still looks interesting, maybe some early warnings will come out via the METO for some areas.

[Duane S.]

Why do iPads do that?? Type a lengthy post, pop over to another tab, come back to this one to finish typing the post, it refreshes and post gone!

Anyway the gist was things looking a little rosier on the 00z suite or at least the 'downgrades' of yesterday have been halted. A much more pleasant environment on here this morning than yesterday. Yes I would say a more mobile weather is currently the favourite for this time next week but before we get there, we have plenty of fun and games. And who's to say a more continental influence isn't just around the corner thereafter?

Forecasters nightmare though when these 'sliders' come into play. Ppn types, location, intensity, duration as energy passes down. Small mesoscale systems can often develop, hardly noticeable but as they meander down in the unstable flow they can be responsible for some big surprise falls in the lucky areas in these sort of setups. So the key word is potential for all. The great thing about living where I do is that expectations are always low, so anything that occurs of the fluffy white variety is always going to be a bonus!

Also just because our hp cell currently over Northern Scandi isn't the most robust looking, it isn't necessarily a bad thing. I like them. Seen it many times before that they tend to linger longer (and often 'nose' westwards towards Iceland in time allowing continued undercutting) whilst those big strong blocks to the NE might look great, the reality is that almost always is their westerly influence stops well east of the UK and whilst it may hinder full on Atlantic mobility, what we often get is the dreaded 'no mans land scenario'. Especially around this time of year.

[Ice Day]

The improvements on the 0z continue on the 6z.  Out to 108, slight shift west, better alignment to the west and maybe the easterly isn't totally dead yet?

 

[SteveB]

Well a nice surprise this morning with snow falling & also started to settle.

 

Some charts for the coming days

 

 

 

I'm not going any further as there's plenty there already to keep most happy.

[mushymanrob]

You've all just read from a professional meteorologist that the meto,with all their amazing technology,are really struggling beyond 2-3 days and yet people are STILL posting charts 7,8,9 days away saying "return to westerlies now set in stone"

 

has anyone actually said its 'set in stone'?...

no of course it isnt, but its looking pretty likely as all models are suggesting that this cold spell will relinquish its grip sometime next weekend.  thats what the models are suggesting so its as relevant to this thread as people posting cold charts in that timeframe (recently).

[IDO]

Why do iPads do that?? Type a lengthy post, pop over to another tab, come back to this one to finish typing the post, it refreshes and post gone!

 

 

Hi. Use a note app like "Drafts" and then copy and paste. Been burnt too many times with my ipad to ever post directly to the browser.

 

At T114 will we get the second slider, chances look better: 

 

Nice run up till then with snow for many.

Edited January 17, 2015 by i'm dreaming of...

[Eugene]

Why do iPads do that?? Type a lengthy post, pop over to another tab, come back to this one to finish typing the post, it refreshes and post gone!

Anyway the gist was things looking a little rosier on the 00z suite or at least the 'downgrades' of yesterday have been halted. A much more pleasant environment on here this morning than yesterday. Yes I would say a more mobile weather is currently the favourite for this time next week but before we get there, we have plenty of fun and games. And who's to say a more continental influence isn't just around the corner thereafter?

Forecasters nightmare though when these 'sliders' come into play. Ppn types, location, intensity, duration as energy passes down. Small mesoscale systems can often develop, hardly noticeable but as they meander down in the unstable flow they can be responsible for some big surprise falls in the lucky areas in these sort of setups. So the key word is potential for all. The great thing about living where I do is that expectations are always low, so anything that occurs of the fluffy white variety is always going to be a bonus!

Also just because our hp cell currently over Northern Scandi isn't the most robust looking, it isn't necessarily a bad thing. I like them. Seen it many times before that they tend to linger longer (and often 'nose' westwards towards Iceland in time allowing continued undercutting) whilst those big strong blocks to the NE might look great, the reality is that almost always is their westerly influence stops well east of the UK and whilst it may hinder full on Atlantic mobility, what we often get is the dreaded 'no mans land scenario'. Especially around this time of year.

 

You must have an older iPad which only has 1GB of system memory, they are notorious for running out of memory when having many tabs open hence they refresh, iPad Air 2 fixes this issue with 2 GB of memory.

 

Yes i agree these strong russian highs are usually too far east,  i prefer highs just to our north.

[Ice Day]

At T114 will we get the second slider, chances look better: gfs-0-114 (2).png

 

Nice run up till then with snow for many.

 

Yes, up to 144 it is a good run, not a belter but another small improvement vs 0z. This thread is in a happier mood today, so perhaps a day of upgrades is ahead of us?

Edited January 17, 2015 by Ice Day

[Captain Shortwave]

Might as well throw in the latest NAVGEM output

Looks okay to me.

The general trend this morning seems to be for low pressure to slide south east through the UK with potentially a brief easterly setting up before the Azores high cuts this off. Still great uncertainty about this though.

Edited January 17, 2015 by Captain shortwave

[The Weather Dragon]

The return of a SW/W airmass by the end of the week is a high probability now - with the current consistent output

Edited January 17, 2015 by Jonathan Evans

[TEITS]

If you compare the 0Z NAVGEM to the 06Z this speaks volumes with regards to the current situation.

 

0Z has the UK in a W/NW,ly flow.

 

http://modeles.meteociel.fr/modeles/navgem/runs/2015011700/navgem-0-150.png?17-05

 

06Z E,ly!

 

http://modeles.meteociel.fr/modeles/navgem/runs/2015011706/navgem-0-144.png?17-11

[Djdazzle]

The return of a SW/W airmass by the end of the week is a high probability now - with the current consistent output

Disagree. It's a possibility for sure, but with the current synoptics, the end of next week is pure fantasy land.

[stewfox]

The return of a SW/W airmass by the end of the week is a high probability now - with the current consistent output

 

Have you advised the met office re high probability. ? Please post the supporting charts where there is consistent model output, an hour ago I thought there wasn't.

Edited January 17, 2015 by Paul
Dropped the un-needed comments

[Team Jo]

Based on the last week of charts I don't think any of the outputs have been especially consistent, on the whole. and that's why we're in a bit of a pickle over the will it/won't it.

That aside, if this is what you're seeing, please post or at least reference the charts that illustrate. - one liners are best placed in the banter thread.....

Thanks!

[Timmytour]

Here's how certain things are.......taking thursday coming up....

The 18z had it...

It's now on the 6z

I don't see how with such a difference in under a week, anything in the longer term can have a "high probability"?

Edited January 17, 2015 by phil nw.
Removed unfriendly comment.

[blizzard81]

If you compare the 0Z NAVGEM to the 06Z this speaks volumes with regards to the current situation.

 

0Z has the UK in a W/NW,ly flow.

 

http://modeles.meteociel.fr/modeles/navgem/runs/2015011700/navgem-0-150.png?17-05

 

06Z E,ly!

 

http://modeles.meteociel.fr/modeles/navgem/runs/2015011706/navgem-0-144.png?17-11

Very good trends this morning and a big improvement on last night's 12z runs. May this new improved trend continue with vigour.

[fergieweather]

Have you advised the met office re high probability. ? Please post the supporting charts where there is consistent model output, an hour ago I thought there wasn't.

The signal is clearly there but how we get from A to B remains uncertain (especially as 'A' has yet to manifest itself!). Quoting UKMO Dep Chief in assessment issued in last hour: "This is going to be a difficult period in which to get forecast details correct. Confidence in a cold start is high, but how mobility returns thereafter is very uncertain. A gradual transition to a more mobile pattern across the Atlantic is likely to gradually take place, through may take until later next weekend to become fully established."

[bluearmy]

Need to be careful re seeing a sou'wester when it could easily be a transient ridge ahead of the next trough dropping se. Check the uppers and thicknesses to see if it's a proper sou'wester.

going back to the modelling and i recall posting that we had a decent chance of running a shortwave into the broad trough around the 21/23 rd as the ah pulled back. Clearly, the reality has been to accelerate the entry to cold and NWP to show the exit by time the best chance of southern snowfall appeared to be a week or so ago.

[egret]

You've all just read from a professional meteorologist that the meto,with all their amazing technology,are really struggling beyond 2-3 days and yet people are STILL posting charts 7,8,9 days away saying "return to westerlies now set in stone"

Yes, and lets remind ourselves what was being shown / said a week or two back when there seemed little hope of cold before the month's end. 

With sunspot activity at (then) current levels the outlook back in early autumn was not one favouing prolonged and severe cold, but did suggest a more 'normal' winter with cold spells and possibly snow.

The current models and associated charts continue to suggest this to me, and yes we can all continue to hope that one throw of the dice throws up a full house that we can all remember fondly.

 

The shift of PV towards Siberia looks far more familiar to me, what we now need is a stronger low down over the Med and better heights in Greenland or Skandi. This set up is not there just now but I would still not bet against it within the next four weeks. As others far more knowledgeable have said in the past - get the bits in the right place and watch the picture develop. And that is the process I love to watch

 

post-7292-0-45015100-1421484484.jpg (drawn from Strat Thread)

Edited January 17, 2015 by egret

[John Badrick]

The return of a SW/W airmass by the end of the week is a high probability now - with the current consistent output

The high Shannon entropy means nothing has a high probability at the moment, nothing is certain, so what's showing in 5/6 days time will chop and change

[weather eater]

Looks to me that part of the problem is the modelling of the lobe of the PV over Greenland, this morning's runs have it further north, only as we get into lower res does this start to drop down. I would not view any return to SWlys as set in stone, likely maybe but not a certainty at the stage.

[phil nw.]

Well after yesterdays model runs, which caused much emotion in the thread, the overnight's and indeed the 06z GFS runs seemed to have trended back west with the trough disruption.

The path seems to be now across the UK and south with eventually a cut off continental low and an easterly by day 5.

 

All the time through the coming days we are in a cold pool of between -6 and -3c with low surface temperatures as the frontal systems come in from the west.

Tues to Thurs look still very interesting for snow chances for many places as we see little wave features develop along the frontal boundary but of course it's too early to put detail on where and how much etc.

The fax at T84hrs-Tuesday

 

forr example shows the first attack with a buckling occlusion over the country.

 

I think the main thing today with the surface features modelled further west again there is little sign of any mild uppers getting into the mix so a greater chance of more people seeing some snow next week.

As for the longevity of the cold spell well the way i look at it we were talking about a 7-8 day period when this pattern became agreed a few days ago.This is what we appear to be getting so anything more will be a bonus imo so nothing has changed in that respect.  

The 00z 2m Warks temp graph

 

a cold week to come.

 

As for week 2 well the naefs and ecm ht anomls. for day10 show little change to the upper pattern

 

 

with continued attacks from the north west into Europe so it's very unlikely we will get a mild flow from that setup.

Indeed it may be worth keeping an eye on the +ve heights to our north east later on- a little more weakening of the vortex and these could very much come into play later.

 

 

[The Weather Dragon]

I just wanted to bring a balanced view

I desperately want the cold and snowy weather to prevail

My take on this after analyzing the various outputs is that the westerly airmass as shown on this mornings GFS will establish itself

[kev238]

It is interesting that fergieweather notes there is a clear signal for a return to a westerly regime- I hope this is noted.

I am always told get the cold in and the snow opportunities will arrive- surely this coming week it a case in point. Embedded cold with a sliding system will produce snow for some though I can't really see snowmageddon occurring. However, a couple of cms caused problems so could be fun and games.

It

[Gowon]

The best chart this morning in terms of prolonging the cold is from the CMA which manages to squeeze some WAA to the NE