Model Output Discussion 17th Dec.2013-12z onwards.

[gottolovethisweather]

Anybody know what the actual overnight charts produced and what the GFS 6z was showing.   Whatever, peace to all men and women, enjoy the festivities and please also have those in our hearts whom have suffered and will continue to suffer due to the unpleasantries of recent weather events.

Edited December 24, 2013 by gottolovethisweather

[No Balls Like Snow Balls]

likewise the same can be said about those only looking at cold in FI. The country has/is being battered by storms and yet there has been precious little discussion about anything inside the reliable timeframe of late. I'm not feeling very charitable this morning after last night and discovering the water that leaked down our chimney!

 

So, in the reliable there is nothing but more wind and rain which are going to cause more problems. Fridays low looks a little less intense further south but still looking bad further north.

 

 

There are some very serious issues to still to come with flooding and damage to trees/property at what is not the ideal time of the year. Let's not overlook that. 

 

In the meantime while we wait for it to snow in FI December and one third of winter has gone. Certain posters got lambasted for suggesting a trend to zonal was likely (although not necessarily showing in the output) in early December while constant cold searching is applauded. The only difference so far is that the zonal has verified. 

 

 

Aye would like to know about the storm being predicted for Friday and the current unsettled pattern rather than the hunt for "no cold". The servere weather thread has been busier than the mod thread lately. Says it all.

 

The current unsettled weather continues on the models i have seen this morning. Perhaps not as extreme as this week though.

Edited December 24, 2013 by No Balls Like Snow Balls

[bluearmy]

likewise the same can be said about those only looking at cold in FI. The country has/is being battered by storms and yet there has been precious little discussion about anything inside the reliable timeframe of late. I'm not feeling very charitable this morning after last night and discovering the water that leaked down our chimney!

 

So, in the reliable there is nothing but more wind and rain which are going to cause more problems. Fridays low looks a little less intense further south but still looking bad further north.

 

 

There are some very serious issues to still to come with flooding and damage to trees/property at what is not the ideal time of the year. Let's not overlook that. 

 

In the meantime while we wait for it to snow in FI December and one third of winter has gone. Certain posters got lambasted for suggesting a trend to zonal was likely (although not necessarily showing in the output) in early December while constant cold searching is applauded. The only difference so far is that the zonal has verified.

Just as we preferred Cecil wotsit as happy days, you were more relaxed when pharaoh clutchstraw!

It's a fair cop - I am biased cold searching in winter, just as warm searching in summer. However, I will try and tell it how it looks and if there are no straws to clutch, then that's what I'll post. at the moment, there are plenty of straws - infact the output, though in deep fi, is explicit in ths regard. If naefs edges into agreement (currently not picking the euro low anomolys), then it will be into full ramp mode!

!

[Frosty.]

The Gfs 06z op run has some very encouraging signs for coldies as time goes on with a much better jet alignment tilting nw / se which brings cold reloads from the northwest / north during early January, so there are possible changes afoot once the current stormy spell starts to ease, the first step is to get low pressure to the east of the uk and enable cold air to sweep down from the north..I would happily take what this 6z run shows in low res.

[Catacol]

Been away for a while in stormy Cornwall. I'm not a huge fan of wind and rain - but wow! Some storm we had in the SW last night.

 

Worth pointing out to all those wringing their hands in frustration at the lack of epic cold that a fortnight or so ago forecasts were put out there by many who know their stuff stating that epic cold would not come in the medium term. It really wasnt a tough pattern to pick - very cold strat, high zonal winds, flattening of the pattern with the aleutian high taking a break, and strat warming that was moderate at best. The vortex has wobbled about a bit, but that's about all.

 

The US warming on around 12/13 Dec duly arrived and the vortex wobbled its way out of Canada to Greenland and has now camped pretty much over the UK. I must admit the run of low pressure has dropped further south than I had expected, and I had also forecast that it would make its way further east more quickly than it has done... but if forecasting was easy it wouldnt be fun!

 

So going into the post Xmas period where next?

 

For sure we are heading for a change in pattern.

 

Over Tibet we have low pressure forecast to hit once again, here the UKMO at 48 hours:

 

 

The growing effect of Asian warming is clear from the charts now - here up at 10hPa for 2nd Jan

 

 

 

but also lower down at 50hPa for the same date:

 

 

Zonal wind speeds on the decline now - the horrible 100 m/s from the upper strat present on this chart at T+96

 

dropping down quite quickly a few days later to a (still pretty powerful) 80 m/s but note also  declining zonal wind speeds right through the strat at 60-70N:

 

 

 

GFS sees the warming the same way, with a strong increase also forecast set to peak according to the most recent run, on 6th Jan here:

 

 

 

What does this mean tropospherically? Pressure from the warming over Asia will continue to force the main thrust of the vortex into the Greenland/Iceland sector but I believe that the elongation of the vortex caused by this pressure is likely to encourage energy to split. Blocking is still a little way off... but a splitting of energy should help introduce more polar maritime air into the mix and colder temperatures as a result. This is already noticeable in long range GFS charts this morning where at 192 the 06z has a reforming of the Canadian segment with another shard back over Siberian

 

 

 

 

The residual trough over the uk should see us under a colder flow as we approach the New Year but I also see it as a turning point towards a pattern where heights will rise over the arctic as a result of Asian warming and a gradual winding down of the vortex as we approach mid January. Medium to long range modelling is picking up increased arctic heights now on a run to run basis.

 

I am gradually joining Chio's camp on this: the warming assault over the New Year looks likely to slow things down but without causing a proper split in the vortex - but a resurgence of warming activity in mid Jan may well lead to a proper split anytime from around 3 weeks from now. An interesting GFS 00 chart this morning for 6th Jan had another low pressure system hitting Tibet and potentially throwing more warmth up into the strat. Typically it has disappeared on the 06z... but long term modelling is showing some consistency in promoting asian warming.

 

So I remain optimistic for a cold second half to winter. Chances of a cold end to January moving into a cold February increasing. Note I say "chances." :-)

Edited December 24, 2013 by Catacol_Highlander

[Froze were the Days]

Following the ECM is like pulling teeth over the last few weeks or so - painful! never seen the models of recent times so reluctant  to bring in anything resembling cold. One after the other after the other of depressions moving eastwards, got a bad feeling about this winter (although only 3 weeks or so old). Very little to cheer about on the other models.

Edited December 24, 2013 by Froze were the Days

[Jason M]

06z ensembles are rolling out and I must admit to being surprised that the muted signal for blocking to our NE has strengthened somewhat. This is around the day 9 and 10 range. There seems to be a trend for low pressure to fill out over or near to the UK rather than slowly transfer to the NE.

Getting the heights is just one challenge though as we now face the additional problem of 850s. Some of the pretty Synoptics in FI will deliver nothing but cold rain. One thing in our favour for once is the fact that were looking into early / mid January so cold pools can form very quickly and sometimes in situ.

Jason

[bluearmy]

06z ensembles are rolling out and I must admit to being surprised that the muted signal for blocking to our NE has strengthened somewhat. This is around the day 9 and 10 range. There seems to be a trend for low pressure to fill out over or near to the UK rather than slowly transfer to the NE. Getting the heights is just one challenge though as we now face the additional problem of 850s. Some of the pretty Synoptics in FI will deliver nothing but cold rain. One thing in our favour for once is the fact that were looking into early / mid January so cold pools can form very quickly and sometimes in situ.Jason

blocking to our east and northeast - definite jason but likely too far away to influence directly. More interested in the 06z ens trending lower heights into Europe over time compared to the 00z suite.

[nick sussex]

Afternoon all

 

What wretched weather for the UK especially with so many people travelling, who needs this drama on Xmas Eve!

 

In terms of the model outputs its getting a little confusing especially with the ECM, its operationals say one thing its mean and spreads another. Whats really causing problems is exactly what happens to this Arctic high and also how long do low heights cling on over Greenland , even though the Arctic high is solidly agreed on its become like pulling teeth to remove a swathe of low heights running east across Svalbard.

 

Sometimes timing is everything, even if you put aside some differences across the NWP the general trend is for the PV to edge nw and then release another attack around day 8 to 10.

 

So what happens with that next wave of incoming missiles?

 

 

Looking at that GFS for 192hrs the circled black features are very likely to verify PV over Canada beginning to edge east, low pressure near the UK, the uncertainty in the middle is really the crux of the matter.

 

The strength of any ridging especially to the n/nw will determine whether theres enough forcing placed on the next missile to disrupt some energy se'wards.

 

if the low just runs across and phases with that over the UK then essentially you lose that opportunity for more energy to head into mainland Europe and force the Azores high further west.

 

 

 

 

 

 

[Richie V]

A quick one liner from me...

Merry xmas all

ps. I'm STILL waiting for my severe gale fix here in yorkshire It's like waiting for snow.

[bluearmy]

 

So what happens with that next wave of incoming missiles?

 

gfsnh-0-192.png

 

Looking at that GFS for 192hrs the circled black features are very likely to verify PV over Canada beginning to edge east, low pressure near the UK, the uncertainty in the middle is really the crux of the matter.

 

The strength of any ridging especially to the n/nw will determine whether theres enough forcing placed on the next missile to disrupt some energy se'wards.

 

if the low just runs across and phases with that over the UK then essentially you lose that opportunity for more energy to head into mainland Europe and force the Azores high further west.

 

i get the feeling that the current plan is for the high coming east following that renewed burst of low heights to draw the azores northwest towards newfoundland, allowing the trough to drop further into europe. of course that can change.

[Stuie]

According to the GFS, NW England and Scotland are on the brink of a record low for the UK. Without doubt it will be a candle affair for many going into Christmas day.

Where can you find out (i.e tomorrow) how low the actual pressure was recorded?  

[Cecil Hogmanay Melchett]

Stop bickering people, it's frustrating enough at other times of year, but to bicker and point score about weather charts on xmas eve is even more ridiculous!

I dont think anyone is bickering Paul

At least im certainly not!

ECM ensembles for DeBilt don't make pretty viewing.Possibly a reflection of a flow off the North sea pointing to trough(s)in our locale.

Acc to Retron on TWO the EC15 dayer is a conveyor belt of lows across the pond,with little or no blocking structures present across Greenland or Scandanvia its very difficult to make a case for anything other than wet and windy with the odd day or two of a lull until the next low hurtles towards the UK.

Anyway,time for some christmas dinner,i can smell the sprouts from the living room!

Merry christmas to all on NW,lets hope for a change of fortunes sometime soon.

[shedhead]

Merry Xmas all - hope Santa delivers what you want, but if imminent northern blocking is top of your wish list there could be some disappointment ahead.  Gotta say nothing in the current output leads me to believe a significant pattern change is likely any time soon. Looks as though the first half of Jan at least will see more of the same in general, though hopefully with time the weather will become less volatile and progressively colder, ahead of what I still think will be a wintry 2nd half of the season. 

 

Enjoy!

[bluearmy]

I dont think anyone is bickering Paul

At least im certainly not!

ECM ensembles for DeBilt don't make pretty viewing.Possibly a reflection of a flow off the North sea pointing to trough(s)in our locale.

Acc to Retron on TWO the EC15 dayer is a conveyor belt of lows across the pond,with little or no blocking structures present across Greenland or Scandanvia its very difficult to make a case for anything other than wet and windy with the odd day or two of a lull until the next low hurtles towards the UK.

Anyway,time for some christmas dinner,i can smell the sprouts from the living room!

Merry christmas to all on NW,lets hope for a change of fortunes sometime soon.

 

you dont have to rely on darren - i posted the 15 day ecm charts earlier.  yes its mobile but the jet aligns more nw/se so the secondary systems will run nw/se into europe.  a bit like what we see over xmas/boxing day but more sustained rather than the trough just being ejected south and cut off.

[IDO]

According to the GFS, NW England and Scotland are on the brink of a record low for the UK. Without doubt it will be a candle affair for many going into Christmas day.

Where can you find out (i.e tomorrow) how low the actual pressure was recorded?

Hi

I use the following link:

http://www.wunderground.com/history/

put in the area and then go to weekly. It will give the max and min reading for surface pressure that week, the min will obviously be today's very low output.

[shedhead]

Well ae least we're not alone for a change. Looks like being one of the mildest Xmas Days across much of central and eastern Europe for many years, even the bulk of lowland Scandi will see maxima above freezing and double digit highs are possible in parts of eastern Europe.

 

I'd imagine the organisers in Sochi will start to have a few sleepless nights if this pattern extends deep into Jan...

 

Edited December 24, 2013 by shedhead

[UV-RAY]

Well ae least we're not alone for a change. Looks like being one of the mildest Xmas Days across much of central and eastern Europe for many years, even the bulk of lowland Scandi will see maxima above freezing and double digit highs are possible in parts of eastern Europe.

 

I'd imagine the organisers in Sochi will start to have a few sleepless nights if this pattern extends deep into Jan...

 

But most here will see temps below average on the big day Shed.

[Airedalejoe]

But most here will see temps below average on the big day Shed.

Glad you said that, thought I was going mad there! It's a cold wind blowing out there and we've just had a light snow shower! Looks even colder tomorrow!

[Frosty.]

But most here will see temps below average on the big day Shed.

Exactly..I wouldn't call 4-7 celsius mild

[swfc]

Merry xmas to all on netweather.The next week to ten days look pretty much sorted and then its whether the arctic ridging makes a move in the right direction and brings a change ?looks to be a gradual trend to some cooler than average temps but as always fi can throw some major changes up sometimes for the better

[TootyFruity]

Just a quickie from me just popped in for a quick gander at the models and to wish everyone a very Merry Christmas and hopefully a Snowy New Year

Take care everyone

TF xxxxx

[Duane S.]

Not cherry picking, well, only to the extent that it follows my thinking of the past 5 days of where we are heading, an MLB. GEFS member 12...

 

A weak polward ridge makes inroads on the Pacific side of the Northern Hemisphere

 

Helping to create to a decent troposheric vortex split of sorts and a decent -AO profile

 

Watch then to our NE as the Russian (glass half empty) Scandi (glass half full) high ridges westards

 

Connection complete and energy is now drawn E / SE underneath.

 

Now look to the Atlantic...

 

WAA surge from the established Mid-Atlantic high bolsters the Mid-Lat heights and lower European heights drop just low enough to stop a sinker

 

Far reaches of FI and just one not-too-shabby outcome

 

Note that this run has no really cold uppers nor does it have what might be classed as decent HLB but it does offer us a viable way out that, to my mind, ties in with upstream signals. There is no realistic route to quick cold from where we are now but if we are heading for the above the potential is there 2nd week onwards for decent cold.

 

 

[Captain Shortwave]

But most here will see temps below average on the big day Shed.

The scariest thing is that we are one of the coldest places in Europe, but we are only just below average ourselves. Shocking for our neighbours on the continent 

Let's hope we get a pattern change soon, or they will have to invent new winter sports 

[UV-RAY]

The scariest thing is that we are one of the coldest places in Europe, but we are only just below average ourselves. Shocking for our neighbours on the continent 

Let's hope we get a pattern change soon, or they will have to invent new winter sports 

Lol, they could always take up our favourite pastime  of dodging the raindrops.