Model output discussion - 1st December onwards

[knocker]

More of the same from the gfs this morning. Periods of rain during the week but the main interest will be whether we break any temp records towards the middle of the week. I suspect it will be close. Purely of academic interest at this stage it has Xmas day in benign SW flow with a low to the west that moves east through Xday and Bday instigating a brief cold plunge.

Chart weatherbell

 

[johnholmes]

Yes much of the same from the last set of anomaly charts last evening and this morning; strong just about westerly 500mb flow into the UK and Europe from trough out west. No sign of any marked let alone major wavelength change yet.

[NO LONGER POSTING]

9 hours ago, knocker said:

Frankly I would think this the worst of both world's. if of course it came to fruition, with severe gales and not a little rain.

 

My word, We were speaking about this over the weekend about the jet firing up, but not to this extent 

[IDO]

With the very high verifications at the moment there will be little changes run to run up to D10, just variations on the theme, and that is true this morning. We have a very mild, possibly record breaking week ahead and into D9:

There will be bouts of rain this week but those high uppers are mostly combined with drier interludes. At D10 all similar with surface conditions and long wave pattern:

Christmas Day similar to the 12z, a N/S split with mild in the south and average to below the further north you move, though the front is further south this morning and a washout for the south:

From then to D16 the GEFS try to build up the heights over the UK with the possibility of another mild plume as we enter the end of December: 

D16>>>

The CFS w3-4 remains steadfast for the early-mid  January pattern with the potential for another mild start to 2016:  

I was looking to hopefully see a pattern change in mid-Jan but that is looking unlikely at the moment and any strat to trop developments look like Feb onwards it is hard to see how we can dislodge this pattern. The heights in the strat showing a stretched PV, but this looks like it needs to be sustained:

The UKMO update their week 3-4 this morning and they are going with the mild and wet scenario with no mention of even cold bursts, and that is what the CFS shows, the jet moving north enough to divert any cold north of most of the UK. CET is +4.7c above average after 12 days!!

[gottolovethisweather]

Hello all.

 

Just thought I'd ask whether we are soon to enter the Summer Solstice period rather than the Winter Solstice, lovely Summer-like conditions forecast for Europe later this week, so clearly its not just US!

 

 

Its also a extended dry scene across vast parts of Europe as well, so not many violent Thunderstorms, no wait I got my seasons wrong again. 

 

 

Soon be Christmas, things will change but if its prolonged cold you're after I'd wait until well after the special day. Certainly, a rampaging Jet bringing along with, its associated storms is looking a high probability in the run up to the 25th, with brief periods where the Jet might dive SE'wards too. Basically, brief shots of NW'rly influenced air bringing brief wintriness mainly up North is the best hope for coldies judging by current signals.I still say something's got to give, christ I heard a Blackbird in full song this morning and believe me, when it does, things will get very very interesting.

I know I'm a bit premature with twelve days of Christmas business but the pipers might be piping before we know it, things can switch around very quickly indeed when it comes to our changing climate.

 

Edited December 14, 2015 by gottolovethisweather

[Frosty.]

The Gfs 00z shows exceptionally mild air set to bathe the uk at times this week, especially the midweek period and then again into next weekend with temperatures into the mid to high 50's F /  nudging 60F in the south, truly amazing and no wonder a lot of spring flowers are already out in force...especially the daffs,  and knocker's AC will be on full blast in the woodshed this week. Christmas week looks more normal for the time of year and the run ends colder!

Edited December 14, 2015 by Frosty.

[Gavin Hannah]

Ok... FI But....

Can we please get this, but only a triffle sooner lol.....

 

Edited December 14, 2015 by Gavin Hannah

[MP-R]

32 minutes ago, Gavin Hannah said:

Ok... FI But....

Can we please get this, but only a triffle sooner lol.....

 

I'm off to Poland from the 26th to the 30th so that would bring some wonderful cold crisp conditions there, and even here for that matter. Alas, these charts have stayed in FI for a while. Having said that, given the setup we are in, it may just be more likely that our first cold spell of the winter might come from that direction rather than the north given the PV's ongoing friendship with Greenland. Other than that, there really isn't anything of interest in the models save for the possibility of some record mild temperatures if the sun is out on Thursday. My December record currently stands at 15C on Christmas Day 2002.

[IDO]

JMA have just updated the JFM and no surprises for January. Clear signal for the Azores/Euro High combo keeping the UK under higher than average pressure: 

That is a very pronounced and strong anomaly. As Fergie isn't posting much this year here are a couple of his recent tweets and these tie in with the LR forecasts:

fergieweather W COUNTRY OUTLOOK V mild conditions develop later this week. Returning closer to avg leading to Xmas (w windy spells); no sign cold weather 14/12/2015, 09:38

fergieweather W COUNTRY OUTLOOK CONT'D Strong signal for generally above avg temps continues into early Jan, w higher pressure into S UK poss to mid-month 14/12/2015, 09:42

The Feb and March anomalies suggest this pattern is going to last throughout the Winter with strong anomalies for the Nov/Dec pattern to be maintained:

I suspect they relate to the El Nino driver and we know once that takes charge then we have a rigid pattern. If there has ever been a Winter where we need a SSW event this is one. Fingers crossed.

 

 

[Nick F]

58 minutes ago, MP-R said:

 Other than that, there really isn't anything of interest in the models save for the possibility of some record mild temperatures if the sun is out on Thursday. My December record currently stands at 15C on Christmas Day 2002.

Looking at the charts, it looks like sunshine may be in short supply on Thursday 17th away from NE Scotland, thanks to the humid southwesterly flow. But despite lack of sun the foehn effect could still bring temperatures higher than those projected by GFS to the lee of high ground such as north Wales, Pennines and Highlands. The date record for max temp for 17th is 17.8C in 1972 at Aber, Gwynedd in north Wales. Be a big ask to beat that, but not out the question.

[MP-R]

8 minutes ago, Nick F said:

Looking at the charts, it looks like sunshine may be in short supply on Thursday 17th away from NE Scotland, thanks to the humid southwesterly flow. But despite lack of sun the foehn effect could still bring temperatures higher than those projected by GFS to the lee of high ground such as north Wales, Pennines and Highlands. The date record for max temp for 17th is 17.8C in 1972 at Aber, Gwynedd in north Wales. Be a big ask to beat that, but not out the question.

And it's not hard to see why with a chart like this:

Interestingly though, uppers were only around 6C compared to the 10-11C progged this week, so must have been quite sunny compared to this coming week. Wouldn't be surprised if it's the night-time temperatures that are most 'impressive' (if you can call it that).

06Z rolling out and I wish it would just get to the end so I can see if that easterly has disappeared or not lol.

[chrisbell-nottheweatherman]

1 hour ago, IDO said:

JMA have just updated the JFM and no surprises for January. Clear signal for the Azores/Euro High combo keeping the UK under higher than average pressure: 

That is a very pronounced and strong anomaly. As Fergie isn't posting much this year here are a couple of his recent tweets and these tie in with the LR forecasts:

fergieweather W COUNTRY OUTLOOK V mild conditions develop later this week. Returning closer to avg leading to Xmas (w windy spells); no sign cold weather 14/12/2015, 09:38

fergieweather W COUNTRY OUTLOOK CONT'D Strong signal for generally above avg temps continues into early Jan, w higher pressure into S UK poss to mid-month 14/12/2015, 09:42

The Feb and March anomalies suggest this pattern is going to last throughout the Winter with strong anomalies for the Nov/Dec pattern to be maintained:

I suspect they relate to the El Nino driver and we know once that takes charge then we have a rigid pattern. If there has ever been a Winter where we need a SSW event this is one. Fingers crossed.

 

 

Are you saying "winter's over"?

[Gavin Hannah]

Well for two back to back runs to have FI charts fairly similar at t.384 is to my mind... a rare thing indeed.

While different conditions on the ground the Scandi-ish HP is still there although maybe more of Scuro HP. Main difference being the HP in the Atlantic is missing as the GFS really devlops the LP system coming out of Canada. If only this were 9-10 days out rather than 16. I would be much more confident in Scandi HP being a possible solution. At this range though, it could easily dissapear. Why do you do this to us GFS.... Why?

 

Edited December 14, 2015 by Gavin Hannah

[IDO]

1 minute ago, chrisbell-nottheweatherman said:

Are you saying "winter's over"?

No. Just what the LR models are showing!

Cohen's AER update should be interesting tomorrow re: stratosphere prospects to influence the trop?

The 06z run promises another very mild spell at the end of December:

   

That repeating pattern again...

[carinthian]

I remember working at Gatwick during the winter or 72/73. We had Euro High and mild feed all the way through December, January and only at the end of the first week of February saw a change of the locked pattern and some colder weather started to prevail. Those days synoptics charts were hand drawn from hourly observations and it became a pain drawing the same pattern ( ie dominant Euro High ), so it came a relief to see this shifted later in the winter. Very limited Model charts those days to indicate how long the mild winter was to prevail !

 C

[nick sussex]

I think we might have to wave the white flag here and write off the rest of December for wintry prospects.

The tightly coiled PV in its expected location is not going anywhere fast. As we've seen from the last few days the models are consistent and reliability in these situations goes up.

So generally you can have a good idea of the likely pattern for up to two weeks. The issues with any ensembles showing a more southerly tracking jet past T240hrs is their bias, with time the jet gets edged north.

For a few days the ECM ensembles have shown a downward trend in their latter stages however this doesn't move forward. So for the timebeing I'd view the longer range with caution until a change is shown within T240hrs which actually moves forward, this being either the movement of the PV or some splits in it. You actually need a catalyst to bring the jet further south so ensembles showing the tightly coiled PV in its expected location with a southerly tracking jet have little chance of verifying.

Theres no point in trying to sugar coat the outputs, these are in terms of cold about the worst you can get which at least means the only way is up.

The current situation is akin to a modern day army( the strong El Nino) fighting with a medieval battalion, until the El Nino weakens then its unlikely we'll see any major changes to the NH.

The only variable that might shuffle the pattern the MJO is normally muted out in strong El Nino years, it rarely survives into a more favourable phase. There is a divergence of opinion there between the outputs. Some ECM ensembles want to take this into a more colder favouring phase however the GFS isn't interested.

Barring any MJO miracles I can't see anything more than some fleeting PM shots at best, the Euro high also looks like hanging around which is very bad news for European ski resorts. I think currently this is looking like one of the worst ever starts to the season. Hopes there rest on a fleeting PM shot surviving far enough se which is still a long shot currently.

I think the best way forward in terms of surviving these hideous outputs is to get to the acceptance stage! My expectations for December are now zero, best we enjoy the festive period and see what January might bring.

 

 

Edited December 14, 2015 by nick sussex

[Walsall Wood Snow]

4 minutes ago, carinthian said:

I remember working at Gatwick during the winter or 72/73. We had Euro High and mild feed all the way through December, January and only at the end of the first week of February saw a change of the locked pattern and some colder weather started to prevail. Those days synoptics charts were hand drawn from hourly observations and it became a pain drawing the same pattern ( ie dominant Euro High ), so it came a relief to see this shifted later in the winter. Very limited Model charts those days to indicate how long the mild winter was to prevail !

 C

I sometimes take comfort from the knowledge that the early to mid 70s Winters were rubbish for cold and snow, especially as before I became interested in past Winter weather I assumed that the 70s were a cold and snowy Winters decade, but it seems that it wasn't until the late 70s and up to the mid 80s that there was a run of cold Winters. Maybe the 2010s will turn out to be a sandwich decade with cold snowy Winters to begin with and what is now turning out to be starting with Winter 2013/14 the mild filler and hopefully the end of the decade reverting back to the cold and snowy theme again. Though there's still time for this Winter to turn itself around, as a cold and snow fan it can't have started much worse.

[mulzy]

Could the winter of 15/16 be comparable to the dreaded winter of 97/98?  I certainly hope not but the signs are not good.

Day 16 NAEFS anomaly shown below indicating strong PV and Euro heights.  What is amazing is that even at day 16 these anomalies are strong.  I'm guessing the ridge over eastern Canada/US is bad news for cold in NW Europe?

 

[nick sussex]

Just now, mulzy said:

Could the winter of 15/16 be comparable to the dreaded winter of 97/98?  I certainly hope not but the signs are not good.

Day 16 NAEFS anomaly shown below indicating strong PV and Euro heights.  What is amazing is that even at day 16 these anomalies are strong.  I'm guessing the ridge over eastern Canada/US is bad news for cold in NW Europe?

 

You must be too young to remember 88/89. That ranks IMO as the worst ever, I don't think the Scottish ski resorts opened at all during that winter. I think much depends on how quickly the El Nino weakens. I'm comfortable in writing off December but for the rest of the winter I think we should keep an open mind.

[mountain shadow]

5 hours ago, chrisbell-nottheweatherman said:

Are you saying "winter's over"?

Based on current model output we can certainly right off any widespread cold spell out to mid January. 

As IDO says and indeed all the Pro forecasters have been saying is that any proper cold this Winter will be late January into February,  and even that is dependent on a SSW occurring. 

[nick sussex]

In terms of the MJO, NCEP do a weekly update. The new one should be out tomorrow but last weeks summary  said the following:

The MJO remained weak during the past week. 
Intraseasonal variability associated with Equatorial Rossby wave and Kelvin waves activity over the central Pacific, and slowly re-emerging atmospheric conditions consistent with El Niño are primarily responsible for the current pattern of tropical anomalous convection. 
Dynamical model forecasts of the MJO index indicate a strengthening signal across the Indian Ocean, with some eastward propagation.  
The role of the MJO is uncertain as some models indicate little to no signal and others indicate a signal that opposes the footprint of the ongoing El Nino.
 

I think the latter point is the issue, it would be very unusual for the MJO to over ride the El Nino.

[Frosty.]

17 minutes ago, nick sussex said:

 

I think the best way forward in terms of surviving these hideous outputs is to get to the acceptance stage!

 

 

Agreed nick, i've reached acceptance now, kicking and screaming acceptanceLOL

Mother nature says it's spring already..and the Astronomical winter starts in one week..bizarre times!!

[AdrianHull]

4 hours ago, IDO said:

With the very high verifications at the moment there will be little changes run to run up to D10, just variations on the theme, and that is true this morning. We have a very mild, possibly record breaking week ahead and into D9:

There will be bouts of rain this week but those high uppers are mostly combined with drier interludes. At D10 all similar with surface conditions and long wave pattern:

Christmas Day similar to the 12z, a N/S split with mild in the south and average to below the further north you move, though the front is further south this morning and a washout for the south:

From then to D16 the GEFS try to build up the heights over the UK with the possibility of another mild plume as we enter the end of December: 

D16>>>

The CFS w3-4 remains steadfast for the early-mid  January pattern with the potential for another mild start to 2016:  

I was looking to hopefully see a pattern change in mid-Jan but that is looking unlikely at the moment and any strat to trop developments look like Feb onwards it is hard to see how we can dislodge this pattern. The heights in the strat showing a stretched PV, but this looks like it needs to be sustained:

The UKMO update their week 3-4 this morning and they are going with the mild and wet scenario with no mention of even cold bursts, and that is what the CFS shows, the jet moving north enough to divert any cold north of most of the UK. CET is +4.7c above average after 12 days!!

As we all know our weather is dynamic. So for you to be writing off winter when it has just barely started looking at ridiculous fantasy island charts really takes the fun away from this page.

I never look beyond the two week time frame . You could be right or wrong who knows. But I wont be wasting my time looking beyond the New Year ;-) 

[nick sussex]

As I'm desperately scratching around for some good news a few words about the current El Nino.

Looking at the Australian update they do think some El Nino indicators suggest it might start weakening. The NCEP update of last week showed a small decline. There will be a new update this evening, we have to bear in mind though that its coming from a very strong peak.

[Glacier Point]

19 minutes ago, nick sussex said:

In terms of the MJO, NCEP do a weekly update. The new one should be out tomorrow but last weeks summary  said the following:

The MJO remained weak during the past week. 
Intraseasonal variability associated with Equatorial Rossby wave and Kelvin waves activity over the central Pacific, and slowly re-emerging atmospheric conditions consistent with El Niño are primarily responsible for the current pattern of tropical anomalous convection. 
Dynamical model forecasts of the MJO index indicate a strengthening signal across the Indian Ocean, with some eastward propagation.  
The role of the MJO is uncertain as some models indicate little to no signal and others indicate a signal that opposes the footprint of the ongoing El Nino.
 

I think the latter point is the issue, it would be very unusual for the MJO to over ride the El Nino.

Worth noting that during November the ENSO signal got trumped by an unusual Indian Ocean convective signal, so it's not the dominant player that it could be.

Today's forecast and updates for the MJO awaited with a lot of interest, as current trend seems to be for coherence and eastward propagation, at least for upper level velocity potential and convective components. Both EC and CFS forecasts currently showing phase 6 progression for week 2. That in itself not particularly useful for shifting the wavelengths, but more significance in terms of raising levels of angular momentum and how that choreographs with the AO and degrees of amplification in the Northern Hemisphere.