Model output discussion - into Christmas

[Jason M]

1 hour ago, IDO said:

Hi, unfortunately shortwaves nearly always scupper cold and rarely bring us cold from changes!

Check at D8-D10 to see how the shortwaves have effected the long-wave pattern? To date various modelling of that low in question has made no difference to the bigger picture. We can only hope that something else pops up that the models have missed that changes the course. I cannot see it ATM.

The short waves are a result of the predominant pattern not the driver of it. A shortwave doesn't scupper anything it simply means that the atmosphere isn't supportive of what were hoping for. Always happy to be proved wrong but I see no evidence whatsoever that any deep cold will arrive at our shores over the next couple of weeks (I'd wager we agree on the last bit).

[IDO]

11 minutes ago, Jason M said:

The short waves are a result of the predominant pattern not the driver of it. A shortwave doesn't scupper anything it simply means that the atmosphere isn't supportive of what were hoping for. Always happy to be proved wrong but I see no evidence whatsoever that any deep cold will arrive at our shores over the next couple of weeks (I'd wager we agree on the last bit).

The trigger-low is an example of scuppering or not, semantics aside whether it is a chicken or egg, they are the perceived bad-boys that we can blame for another fail.

Yes, no sign of cold for the foreseeable.

Edited December 20, 2019 by IDO

[Methuselah]

The GEFS 06Z ensembles look interesting:

    

    

Looking at the huge discrepancy between T850 and 2m temperatures (much colder 2m on control?) suggests that wind-strength/-direction could be crucial factors...? Alternatively, all the above could be nonsense!

[Anthony Burden]

GEM very keen on bringing a wintery scenario from the 27th all due to a low pressure finding it’s way to the 

east of us pulling cold north to northeast winds down.Then the high pressure positioning to the northwest 

about as good as you can get for cold weather lovers.

[JeffC]

3 minutes ago, General Cluster said:

The GEFS 06Z ensembles look interesting:

    

    

Looking at the huge discrepancy between T850 and 2m temperatures (much colder 2m on control?) suggests that wind-strength/-direction could be crucial factors...? Alternatively, all the above could be nonsense!

Current safe bet would be your final sentence 

[Ali1977]

A tweet from a certain METO person suggests the Xmas dry period my only be temporary - if GLOSEA is seeing a change where’s that coming from I wonder!! Presumably the West as per the ECM, unlike the GFS that has HP on most of us for most the run!! More changes to come next few runs, as most people expect I guess!! 
 

I don’t really fancy this set up, especially for an early Jan skiing hol as these European HPs tend to last!! 

Edited December 20, 2019 by Ali1977

[johnholmes]

3 hours ago, mushymanrob said:

The NOAA chart i posted on December 9th, predictive for the 17th - 23rd. Compare with the current GFS, out now... id suggest the NOAA chart is pretty much bang on. im not sure why these are somewhat ignored tbh.

You are preaching to your No 1 fan of these charts, BUT they take quite a lot of experience to use and one has to try and be totally objective about them. You show a good example of them, folks they are not always so close!

So what does that from last evening show 

the 6-10 and the 8-14 suggest for the upper air pattern over the UK?

No comments from me as I've only just switched on my pc. Maybe be back later!

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[Kirkcaldy Weather]

12 hours ago, Timmytour said:

I guarantee there will be no easterly this winter. 

 If we are able to "guarantee" what the weather will / wont do why do we look at the models / teleconnections and come on this forum? - because there is no guarantee with the weather and around the world year on year we continue to see weather events that amaze us and some that people may not have thought were possible - this summers record heat in UK, hurricanes, current heat in Australia etc

3 hours ago, northwestsnow said:

There is a 1050 mb monster Siberian high on 6z, 

 

Yes I still believe this is one of the key areas and so much differences run to run continue to show that the models are struggling with that higher pressure, small shifts of that higher pressure and associated colder air can make a big difference to the overall pattern...

2 hours ago, E17boy said:

 

Anyway back to the models and the outlook. To be honest I am feeling a bit low hearted at the moment. Although the models are all over the place, there is no strong evidence that a cold pattern is on the horizon ( although temperatures may drop but not what we want). What is a real concern for me at the moment and the reason to be downbeat is what could go wrong with this high pressure if it does not go to sit where We want it after Christmas ( presuming we do get this high pressure come over). I know yesterday there was a bit of excitement that there may be an undercut and we may see an Easterly, but that seems to be a llow chance ( it could still turnaround who knows) The thing that is really bothering me and probably a lot of us deep down know that this could be reality. If this high moved in a southeast direction, then we have a problem. I touched on this yesterday the doors could open to a southwesterly pattern in the new year. If this does happen sometimes these patterns are hard to get out of and could last for a couple of weeks if not more. I don't want to put a downbeat on us coldies but this is the worse case senaroo that could come out of this and I am being really honest about this. Considering we will already be 4 weeks in winter and having a southwesterly could take out another couple or several weeks it is a scary thought. Allso look at Europe where is the cold?? What are we going to tap into if we were to get an Easterly. I am still keeping an eye on how temperatures fluctuate in the coming days.

 

A key point models are struggling as I mentioned above and small changes could have bigger overall effects for both sides of the coin (cold/less cold). That is often the thrill with chasing cold weather for the UK and yes more often than not we end up on the disappointing side of things but that wont always be the case..

As I mentioned a few day ago the easterly is the jackpot scenario and always the risk that the higher pressure wont align favourably (still has to develop of course) but given the fact that the models are still struggling to get conditions pinned down for Christmas day - 5 days away, still all options on the table.

Keep an eye on the colder air across Siberia, wouldn't take much for it to move west like last nights GFS showed.

[mushymanrob]

45 minutes ago, johnholmes said:

You are preaching to your No 1 fan of these charts, BUT they take quite a lot of experience to use and one has to try and be totally objective about them. You show a good example of them, folks they are not always so close!

So what does that from last evening show 

the 6-10 and the 8-14 suggest for the upper air pattern over the UK?

No comments from me as I've only just switched on my pc. Maybe be back later!

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

It was your research john... i always cite that on a site a co-run.

Ridging dominating, a mean southwesterly flow, mild and on the drier side of average, most unsettled in the northwest, driest on the southeast. Ridging backing more sw/ne in orientation axis roughly east of the Azores through to Norway, retaining mild mean southwesterlies on its northern flank. Mild and dry, rather overcast in the northwest, brighter in the southeast, which look cooler overnight under clearer skies. Possible colder pooling into central europe.
The below chart is about the closest i can find, imho, but the lower (southern) end of the ridge is a little too far east for an exact match, it should be sitting between Iberia and the Azores.
I match the nearest "op" to the Anomaly , then read it from there... We all have our preferred method, but that the one i use and am comfortable enough with to broadcast it.



 

Edited December 20, 2019 by mushymanrob

[Tim Bland]

42 minutes ago, johnholmes said:

You are preaching to your No 1 fan of these charts, BUT they take quite a lot of experience to use and one has to try and be totally objective about them. You show a good example of them, folks they are not always so close!

So what does that from last evening show 

the 6-10 and the 8-14 suggest for the upper air pattern over the UK?

No comments from me as I've only just switched on my pc. Maybe be back later!

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

As you say John - They take a lot of expertise to disseminate. I’ve been viewing models since the days of snow watch on the BBC weather site, but how can I tell by looking at this if it will snow in Carlisle  

[mushymanrob]

3 minutes ago, Tim Bland said:

As you say John - They take a lot of expertise to disseminate. I’ve been viewing models since the days of snow watch on the BBC weather site, but how can I tell by looking at this if it will snow in Carlisle  

Thats high pressure domination with a mean southwesterly... unlikely to snow off that!.
edit ... its mobile though so ridging dominating as opposed to a high pressure cell.

Edited December 20, 2019 by mushymanrob

[Duane S.]

Hmmm. Who's right, who's wrong??

A somewhat differing stance regards future Pacifc activity.

GFS goes very bold indeed, with no memebers even making a fleeting appearance back inside the COD post 5 days, whilst the EC hardly even entertains the notion.

 

[Tim Bland]

3 minutes ago, mushymanrob said:

Thats high pressure domination with a mean southwesterly... unlikely to snow off that!.
edit ... its mobile though so ridging dominating as opposed to a high pressure cell.

Thanks Mushy, how about the Alps as selfishly that’s where I’ll be

[johnholmes]

Depends where and how high, some areas have managed fairly well but a lot, including 'my' area have had high winds, at times the dreaded fohn, stripping the snow base back. I'm just about to post in the winter ski area showing how this affects some areas using the Jungfrau region as an example. Nothing and mean nothing is running today, not the first time since the area opened back end of November (at least on a limited basis), no trains, gondolas, chair lifts etc. Yet the prediction, even from the Swiss Weather service is for a good dumping of snow over the coming few days. Then sunny and shirt sleeves Xmas Day on! Crazy

 

[Johnp]

2 hours ago, Ali1977 said:

A tweet from a certain METO person suggests the Xmas dry period my only be temporary - if GLOSEA is seeing a change where’s that coming from I wonder!! Presumably the West as per the ECM, unlike the GFS that has HP on most of us for most the run!! More changes to come next few runs, as most people expect I guess!! 
 

I don’t really fancy this set up, especially for an early Jan skiing hol as these European HPs tend to last!! 

Well Boxing day looks very unsettled according to Icon!

 

[Timmytour]

32 minutes ago, Kirkcaldy Weather said:

 If we are able to "guarantee" what the weather will / wont do why do we look at the models / teleconnections and come on this forum? - because there is no guarantee with the weather and around the world year on year we continue to see weather events that amaze us and some that people may not have thought were possible - this summers record heat in UK, hurricanes, current heat in Australia etc

Never underestimate the power of reverse psychology 

[swfc]

Tbh so far today there's very little to stir the wintry cockles of my heart.the big hope was dry weather"can the bar get any lower"so hopefully that happens over xmas.im sure there will be the odd winter 87 Armageddon chart but in real terms any "Siberian"heighths for me are not on the table atm.see what ukmo brings?

Edited December 20, 2019 by swfc

[Ali1977]

UKMO at 120 looks better 

 

And at 144, where’s that WAA going

Edited December 20, 2019 by Ali1977

[carinthian]

Evening, think there is some uncertainty at UK Met Office going forward from Christmas Day. Tonights runs will be very interesting. Wonder if UKMO will be going alone !

 C

[SLEETY]

UK met better at 120 big 144 chart coming up..

.

[Ali1977]

1 minute ago, carinthian said:

Evening, think there is some uncertainty at UK Met Office going forward from Christmas Day. Tonights runs will be very interesting. Wonder if UKMO will be going alone !

 C

That UKMO looks great at 144, great start!! And GFS looking like following 

Edited December 20, 2019 by Ali1977

[SLEETY]

2 minutes ago, SLEETY said:

UK met better at 120 big 144 chart coming up..

.

UK meto could go either way at t 144 good luck predicting after that timescale.Can see why the ensembles are all over the place now.

[swfc]

2 minutes ago, Ali1977 said:

That UKMO looks great at 144, great start!!

It looks dry with a ridge so guess that's a plus

[Ali1977]

At 132 the Little cut off low stays in the Atlantic, much better GFS coming up and great that the UKMO was v good. 

[feb1991blizzard]

More fantastic shortwave pattern modelling by the GFS................