Model output discussion - 1st December onwards

[Summer Sun]

GFS gives temperatures widely in the mid teens for England and Wales next Thursday, parts of north west France are not far of 20c!

 

Southern parts of Portugal and Spain have temps in the low to mid 20's

[Newberryone]

For northwestern parts especially, but not exclusively of course, another very wet look to Ecm 00z op with potential for renewed flooding episodes. Not unprecedented weather setup by any means unfortunately because of our latitude. Latter stages of this suite does however offer up some grain of hope with generally a sign of more heights in the south Atlantic and the jet stream pushed slightly further north as a consequence, but then again, how many times has the Ecm been guilty of overdoing heights especially towards the end of many runs. 

[nick sussex]

Some very disappointing outputs all round today. In terms of cold potential you'd need to send the search party out.

At this point its best to have low expectations for the rest of the month and then if something pops up then its a nice surprise.

The upstream pattern looks very flat and with the PV in a bad mood this isn't a great mixture for cold. The Euro high won't depart the scene unless its pulled west by more amplification in the eastern USA/west Atlantic.

Again I'd urge caution with the outputs and ensembles if they show the jet further south in FI, they tend to do this at the longer range with this type of set up so unless this is shown within the T168hrs then I'd be a bit wary.

 

[nick sussex]

1 hour ago, Blitzen said:

Anyone know what this is about and what it would mean?  Don't think I've heard it mentioned.

https://twitter.com/RyanMaue/status/674808091028774912

My first thoughts are that this is bad news for cold potential for Europe. Theres no proper height rises forecast in that area, there is often some confusion with high pressure over Greenland because of the topography and cold, you'll often see the SLP charts showing what at first hand looks like HP but the thing to look out for is the colours on the charts, as a rough guide proper high pressure is shown in varying degrees from green to orange depending on the strength, any high shown there with the blues, purples signifies a surface feature brought about by the intense cold.

[chrisbell-nottheweatherman]

I don't know if this is of any use, but I'm just viewing a Youtube video by Simon Keeling from Weatherweb, and he reckons the GFS is worse than before the upgrade as it's dramatically-overplaying low heights in the Atlantic.  They are strongly favouring the ECM at present.

https://www.youtube.com/watch?v=PkDmsPq5gs8

 

[Geordiesnow]

I don't know what the December temp record is but there is definately the potential for it to be broken surely into the middle of next week with such a long Southerly flow. 

That said, that sort of set up whilst likely to occur in some form is not a definate and no doubt there be variable changes between now and then. Rainfall amounts still needs to be watched also as low pressure systems will start to become slow moving. 

The trend towards mild to very mild is very much there and it will be interesting too see just how mild it will get. 

[blitzen]

4 minutes ago, nick sussex said:

My first thoughts are that this is bad news for cold potential for Europe. Theres no proper height rises forecast in that area, there is often some confusion with high pressure over Greenland because of the topography and cold, you'll often see the SLP charts showing what at first hand looks like HP but the thing to look out for is the colours on the charts, as a rough guide proper high pressure is shown in varying degrees from green to orange depending on the strength, any high shown there with the blues, purples signifies a surface feature brought about by the intense cold.

Thanks for that Nick.

I'm sort of (hoping) that old Mother Nature will  redress the balance of recent weather activity.   Weather, although cool here in east central Scotland over the Summer months, was very, very dry.   Now look at it!

[cheeky_monkey]

2 hours ago, MP-R said:

I think it's been established that there is no typical El Nino pattern as pretty much every event has produced different weather patterns.

 

Not sure this is strictly correct..Gavin Partridge did a very interesting vid on the analogues of different types of El-Nino events..strong basin wide events as we have now always seem to produce mild winters for Europe and the British Isles.

[nick sussex]

6 minutes ago, Blitzen said:

Thanks for that Nick.

I'm sort of (hoping) that old Mother Nature will  redress the balance of recent weather activity.   Weather, although cool here in east central Scotland over the Summer months, was very, very dry.   Now look at it!

You're welcome. Well its a bit reverse down here with the Euro high having been in charge for what seems an eternity bar one week which saw something colder and wetter. Indeed we tend to have less rain here in the winter than the summer which tends to have quite a lot of thunderstorms( which I hate!).

In terms of nature redressing the balance I hope so. Funnily here at this time of year we get a large migration of I think geese which set up in the farmers fields. They are non stop cackling 24 hours and then normally after a brief stint they head further south however because of the very mild weather I think they've decided to set up shop, why go to Africa when African weather has come here!

Regardless of how bleak the outputs are for some proper cold big changes can and do happen, although I think some patience and gritting of teeth is going to be needed. The background El Nino is really making things difficult, I'm happy to hold on for a while, however I will be likely throwing my toys out of the pram if this ghastly Euro high isn't sent packing soon.

Its pretty disastrous for the ski resorts especially coming at the busiest time of the year, I'm hoping for a minor miracle not in terms of something very cold but just even some averagish westerlies to deliver some snow to the mountains.

[Roy]

24 minutes ago, Geordiesnow said:

I don't know what the December temp record is but there is definately the potential for it to be broken surely into the middle of next week with such a long Southerly flow. 

That said, that sort of set up whilst likely to occur in some form is not a definate and no doubt there be variable changes between now and then. Rainfall amounts still needs to be watched also as low pressure systems will start to become slow moving. 

The trend towards mild to very mild is very much there and it will be interesting too see just how mild it will get. 

Just looked up record max for December. 18.3 in Achnashellach, 2nd  Dec 1948

[Cheese Rice]

3 hours ago, IDO said:

High ground only event (>200 metres) so Peak District a possible along with Pennines:

UKMO warning: http://www.metoffice.gov.uk/public/weather/warnings/#?tab=warnings&map=Warnings&zoom=5&lon=-3.50&lat=55.50&fcTime=1449878400

Uncertainty as always with snow forecasts but most other models are over the Peak District area (do not know what netweather uses):

  GFS:  

 

There's higher resolution charts available on meteociel 

 

The snow line will get right down to sea level, freezing level around 100m + any evaporating cooling.

 

 

Can't rule out accumulations to lower levels under such intensity, probably transient, but anywhere above 100-150m could see significant accumulations. 

 

 

Edited December 11, 2015 by Cheese Rice

[Methuselah]

5 minutes ago, Roy said:

Just looked up record max for December. 18.3 in Achnashellach, 2nd  Dec 1948

That would likely have been down to the Fohn Effect; a strong long-fetch of warm and humid air can produce some extraordinary temperatures, in that part of the world...

Can Nature redress the balance? I don't really know, as I get confused between applying any sort of intentionality to Nature, and the wonders of statistical hindsight.

Whatever, the models are clearly implying a very mild outlook period.

[MP-R]

31 minutes ago, cheeky_monkey said:

Not sure this is strictly correct..Gavin Partridge did a very interesting vid on the analogues of different types of El-Nino events..strong basin wide events as we have now always seem to produce mild winters for Europe and the British Isles.

Yes I saw that vid, and very good it was. Although, the fact that this December has already been quite different to December 1997 (I believe the best analogue for this December from what I've heard) keeps the uncertainty in my mind.

[gottolovethisweather]

30 minutes ago, Ed Stone said:

Can Nature redress the balance? I don't really know, as I get confused between applying any sort of intentionality to Nature, and the wonders of statistical hindsight.

Whatever, the models are clearly implying a very mild outlook period.

I'd say Mother Nature often is the bigger player in our globe's atmosphere, i.e. something beyond our control although humanity is inflicting greater changes per se. If there wasn't some sort of balance in place out there we and our wildlife and other living things would cease to exit I'd suspect. However, with all the recent extreme events witnessed in may recent years, the Natural World is fighting against an ever warmer world which makes that balance ever more precarious as the years tick by. As I'm another poster whose causing this thread to drift ever further off-topic I best stop right now.  

As for the current very mild outlook, that'll change to something more akin to average overall I suspect over the next couple of runs. I believe the weather headlines in future weeks could have an European bias to them, as eventually, I firmly believe something's got to give with regards to approaching entrenched cold and snowfalls over there. 

Edited December 11, 2015 by gottolovethisweather

[Frosty.]

There is festive wintry potential sprinkled through the GEFS 6z perturbations, the control run for example and the 6z op charts I posted earlier. Those who are hoping for a mushy mild christmas could be disappointed.

As for those comments yesterday talking about extreme bias, be it mild or cold and wanting dry boring, grey sober comments on the models, I think to take away the personal views of posters would completely remove the fun element that steve murr mentioned recently and would actually put a lot of folk off , both from posting and reading the model output discussion  but that's just my own view...sorry if you don't agree. 

[Polar Maritime]

Yes lets try and keep discussion to what the models are 'showing' in here please.

Thanks, PM

[jvenge]

1 hour ago, Frosty. said:

There is festive wintry potential sprinkled through the GEFS 6z perturbations, the control run for example and the 6z op charts I posted earlier. Those who are hoping for a mushy mild christmas could be disappointed.

As for those comments yesterday talking about extreme bias, be it mild or cold and wanting dry boring, grey sober comments on the models, I think to take away the personal views of posters would completely remove the fun element that steve murr mentioned recently and would actually put a lot of folk off , both from posting and reading the model output discussion  but that's just my own view...sorry if you don't agree. 

I don't think anyone really wants a warm and mushy Christmas :-)

The GSF members look all over the place after day 6 to be honest. I'm looking at them from my part of the World and I could be enjoying anything from -9 to +6 just 6 days out. 

Edited December 11, 2015 by jvenge

[Gavin Hannah]

Yes the 06z does indeed bring some festive cheer compared to the 00z lol. Output flip flopping between seasonal goodness and un-seasonal nightmare for the big day....

[Liam J]

Warmer air further north on the 12z with 12c 850's into the SW and 10c up to N England, is this really a chart for mid December! .... 

Edited December 11, 2015 by *Sub*Zero*

[Captain Shortwave]

Mid teens widely across England by next Thursday if the GFS is  correct.

16/17C in favoured spots I reckon if it came off.

But......

UKMO

The UKMO holds the tropospheric vortex on the Siberian side with weak heights over southern Greenland which drives the jet further south meaning wetter conditions more widely compared to the GFS. Also of course not as mild though temperatures would still likely be balancing out above normal at this point.

[warrenb]

I think GFS has got this wrong, that low just sits in the atlantic meandering around for to long.

[gottolovethisweather]

23 minutes ago, *Sub*Zero* said:

Warmer air further north on the 12z with 12c 850's into the SW and 10c up to N England, is this really a chart for mid December! .... 

It's certainly not in its rightful place and time in the seasonal calendar, I think might I go looking and listening for those Cuckoos soon at this rate, nevermind the Daffodils. Verification chances aren't even that high or low given its only a six day chart so anything's possible, it might come off as shown who knows?  I am however hopefully jesting about seeing our migrant African birds being back in the country by this time next week. 

Edited December 11, 2015 by gottolovethisweather

[Methuselah]

Well, if the model predictions pan out, we can wave goodbye to a sub-10C annual CET...Or, even a sub-10C December?

[johnholmes]

12 minutes ago, warrenb said:

I think GFS has got this wrong, that low just sits in the atlantic meandering around for to long.

Why would it be wrong? The upper air pattern GFS predicts seems to support what it is doing. Of course that may be wrong but it fits the 12z output but how consistent is that with the 12z yesterday or say the ECMWF at the same period? I ask because I have not yet had time to do a comparison.

 

[gottolovethisweather]

3 minutes ago, Ed Stone said:

Well, if the model predictions pan out, we can wave goodbye to a sub-10C annual CET...Or, even a sub-10C December?

I'll give you that one, maybe January though. I'll be watching Central and Eastern Europe's developments closely these coming weeks.