Model Output Discussion 18th Nov.2013-12z onwards.

[Troubleatmill]

Hi Chiono...the point I was making is I think most would prefer the return of zonality over anticyclonic gloom type synoptics, as at least zonality gives us a chance to develop something colder further down the line. As for the private poll, the answer is no.

 

Hi Shed, not sure about that, prefer frosty quiet days to mild rainy days, sure most do. I remember there was the same argument back in 2010 when we had a ridge to our west that seem to just sit there and do nothing. mostly dry and settled but zero chance of snow either. A lot said they wanted it gone so we could start over. However a week later BOOM!! not saying we are in that situation but its not too disimilar either

Edited November 25, 2013 by tempestas

[draztik]

So much doom, gloom and despair in here! Heres a positive, its exactly one month till Christmas so i say, let shed be the Grinch, frosty be the expectant kid on Christmas morning - and let the weather be the weather!

Now the models

There seems, at this stage, broad agreement with NAEFs & ext ecm ensembles trending towards a period of below average values - before a return to something nearer average. The ecm ens have heights to our West & NW while troughing is close by to our NE from days 10-14; but this is only temporary, as more energy is pushed into Greenland, forcing the high further to our East, meaning a return to average conditions overall.

below is day 10/13/15 for the ext ensembles from ecm [height anomalies]

[Joe Levy]

http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=189&y=176 Bearing in mind that these ensembles are for Exeter, this is a pretty chilly set!

This is for Northern England http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=252&y=2 I think it speaks for itself!

Edited November 25, 2013 by Joe Levy

[gottolovethisweather]

http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=189&y=176 Bearing in mind that these ensembles are for Exeter, this is a pretty chilly set!

This is for Northern England http://www.meteociel.fr/cartes_obs/gens_display.php?ext=1&x=252&y=2 I think it speaks for itself!

 

Indeed the cold is already here, really.

 

For those following this MOD discussion from the outside, what's missing, depending on one's preference is a period of more active weather, be that mild SW'rly driven zonal, or a NW'ly driven zonal (my current bet FWIW) or the potentially EPIC charts produced by a NE'rly flow. I'll wait things out for now but those ensembles Joe has attached, along with the GEFS suite do indicate a more prolonged weather situation taking over by my own much touted 3rd December timeframe. Give or take day to day differences, the broad outlook remains the same over the next seven to ten days. I'm convinced this week's runs will start to offer us something more to talk about as the timeframes alluded to, will start firming up on the new expected synoptic profile.

Edited November 25, 2013 by gottolovethisweather

[Joe Levy]

Indeed the cold is already here, really.

 

For those following this MOD discussion from the outside, what's missing, depending on one's preference is a period of more active weather, be that mild SW'rly driven zonal, or a NW'ly driven zonal (my current bet FWIW) or the potentially EPIC charts produced by a NE'rly flow. I'll wait things out for now but those ensembles Joe has attached, along with the GEFS suite do indicate a more prolonged weather situation taking over by my own much touted 3rd December timeframe. Give or take day to day differences, the broad outlook remains the same over the next seven to ten days. I'm convinced this week's runs will start to offer us something more to talk about as the timeframes alluded to, will start firming up on the new synoptic profile.

Also it's worth noting that on that set of ens, even though many runs do turn mild at some point, the majority also turn cold at some point as well, it's just that they're not synchronised, so whilst one run might show cold earlier on, another shows it later. I suppose this raises an important point about how we read the ensembles - a broad spread of runs doesn't always mean disagreement on the type of weather, it can often mean disagreement on precisely when different types of weather are likely to occur! 

[That ECM]

Are you basing the end of ridge domination and the return of zonality on the ensembles Shed? Because that is not what I see, more a continuance of the ridge after a brief weakening. And why do you say that most of us won't be too disappointed to see the gradual onset of zonality when you jolly well know that most of us would much prefer cold synoptics to show - or have you completed a private poll of MOD members wishes that only you are privy too?

Continuance of the ridge after a brief weakening is how the met o see it as well. 6 to 15 day puts in words that outlook perfectly.

[johnholmes]

Hi John It's not a case of not being bothered and I would be glad to post it myself at some point. It does take a lot of time to transfer data from a website to various forums day to day and I recently pm'd Summer Sun giving indication that I was more than happy for him to continue to post it across on my behalf. This is my busy time of year with my craft business and even my website might miss a few updates at times, especially weekends. However, after Christmas and into the  New Year when we get into the business end of winter I should be free enough to post them across myself if you folks wish. Meanwhile guys thanks for your support.

 

thanks for that Gibby

[yorkieblade]

With reference to shedheads last post. Did some posters say last week that the models will fluctuate and probably show zonal until the vortex has relocated over siberia /Russia? Just asking

People like John Holmes & Gibby  for me "tells it how it is" , no hope or wish casting , I have been following this forum for a few years and experiance tells me that certain posters tend to post charts that suit their preferred outcome, I must admit as a novice myself it becomes difficult ,but you will through experiance find out the which members are more or less on the money.Please don't be put off !!

[Yarmy]

Is there any truth in the oft-mentioned zonal reset? In other words, are you more likely to get an evolution to significant cold from a zonal start than from the synoptics we have currently? Seems unlikely to me. 

[shedhead]

Hi Shed, not sure about that, prefer frosty quiet days to mild rainy days, sure most do. I remember there was the same argument back in 2010 when we had a ridge to our west that seem to just sit there and do nothing. mostly dry and settled but zero chance of snow either. A lot said they wanted it gone so we could start over. However a week later BOOM!! not saying we are in that situation but its not too disimilar either

Hi tempestas, not suggesting a cold pattern cannot develop from the current synoptics, or indeed any pattern for that matter given sufficient time, but in the case of 2010 the overall profile farther north was somewhat different to now.  Until we see the Jet pushed well south any sustained HLB looks very unlikely to me, so I think we would ultimately benefit from a sig spell of zonality, but FWIW I also think we will be looking at late Jan/Feb before this eventually happens.

Edited November 25, 2013 by shedhead

[nick sussex]

Is there any truth in the oft-mentioned zonal reset? In other words, are you more likely to get an evolution to significant cold from a zonal start than from the synoptics we have currently? Seems unlikely to me. 

That's an interesting question, historically speaking when you have a MLB this will go one of two ways, either the pattern in the NH becomes favourable which then eventually leads to retrogression of the high and a cold spell or snap or this sinks as the PV finally wins the battle.

 

In the winters before the recent colder ones a MLB generally only went one way and that was to a period of mild zonality, in more recent times we have seen more retrogression, at the moment the high sinking doesn't look like a definite zonal mild because of the upstream pattern which still retains some amplification and the Pacific ridge is still trying weaken the PV to the north.

 

The key really is where the main chunk of the PV goes, if its stays towards Siberia then that reduces the chances of an extended spell of mild sw'erlies, the flow into the UK given the overall trends looks mostly  between west and nw,  to get some proper Arctic air we'd need to see more amplification upstream and the removal of low heights to the north.

 

The current pattern is neither terrible  or inspiring its all a bit beige if you know what I mean!

Edited November 25, 2013 by nick sussex

[Gael_Force]

That's an interesting question, historically speaking when you have a MLB this will go one of two ways, either the pattern in the NH becomes favourable which then eventually leads to retrogression of the high and a cold spell or snap or this sinks as the PV finally wins the battle.

 

In the winters before the recent colder ones a MLB generally only went one way and that was to a period of mild zonality, in more recent times we have seen more retrogression, at the moment the high sinking doesn't look like a definite zonal mild because of the upstream pattern which still remains some amplification and the Pacific ridge is still trying weaken the PV to the north.

 

The key really is where the main chunk of the PV goes, if its stays towards Siberia then that reduces the chances of an extended spell of mild sw'erlies, the flow into the UK given the overall trends looks mostly  between west and nw,  to get some proper Arctic air we'd need to see more amplification upstream and the removal of low heights to the north.

 

The current pattern is neither terrible  or inspiring its all a bit beige if you know what I mean!

 

Looking at our skies, I think the new greige might be a better description.

[bluearmy]

can anyone point me to a 'zonal reset' that brought about a cold period for the uk (as a whole)? not a couple of days of mobility but a proper change to wsw zonality. ive been doing this for too many years and i cant remember one. be careful what you wish for.

[Snowman.]

Hi Chiono...the point I was making is I think most would prefer the return of zonality over anticyclonic gloom type synoptics, as at least zonality gives us a chance to develop something colder further down the line. As for the private poll, the answer is no.

It really doesn't

 

Having a block causes disruption to your regular set-up a return to zonal conditions would leave a raging PV over Greenland which then we would need to focus on disruption in the stratosphere to get anything decent, however there is obviously exceptions.

 

I'm happy with the way things are turning out its the lack of consistency is troubling me and making me anxious.  

Edited November 25, 2013 by SN0WM4N

[Snowman.]

Could you explain this a little more please SNOWM4N (or someone else) for those of us who don't understand what it shows? Thank you.

Here ---> http://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/

 

Your best man for explaining things is Chino as he is an expert.

 

This is only my second year doing this so I have much to learn in the way the Strat behaves and what not.

[Weather of Mass Disruption]

USA cold looks epic

 Feels like the United States always gets a pasting...

 

...about time we had one to rival them! 

[Methuselah]

can anyone point me to a 'zonal reset' that brought about a cold period for the uk (as a whole)? not a couple of days of mobility but a proper change to wsw zonality. ive been doing this for too many years and i cant remember one. be careful what you wish for.

I remember a lot of 'zonal resets' during the 1990s. 1989 had too many to count!

 

I'd have though that there's more likelihood of 'eventually' seeing cold weather from what we currently have, than from full-on zonality; and, fortunately for us, no model is suggestive of it.

[Troubleatmill]

can anyone point me to a 'zonal reset' that brought about a cold period for the uk (as a whole)? not a couple of days of mobility but a proper change to wsw zonality. ive been doing this for too many years and i cant remember one. be careful what you wish for.

 Indeed a full zonal reset means PV rooted over Greenland, spawning low after low for the UK. Muddy paws for the dog everyday, flooding in the fields, Car totally filthy, leaky drain pipes, money for new waterproofs cos theve been washed too many times, PNE attendances going down, people in misery, GDP falling, civil unrest in the streets, total chaos!

 

Nice and quiet if not cold and snowy  

Edited November 25, 2013 by tempestas

[Snowman.]

What you're looking for in models is sending the reaming pressure system(s) around Greenland south this allows the ridge from Canada to extend Eastward dragging are block north-west creating a small time frame for us to get something.

 

The main thing we're looking for now is sending it south rather than over or leaving it lingering.

 

ECM is pretty messy but I reckon it would get there eventually GEM is much better but not perfect, as for the GFS it's keep a trough in Canada rather than sending it south into the states.

 

 

Edited November 25, 2013 by SN0WM4N

[nick sussex]

 Feels like the United States always gets a pasting...

 

...about time we had one to rival them! 

You can look at it two ways, yes they get some epic snow at times, but they also get those awful tornados. Of course a nw flow into the eastern USA isn't modified by sea track so its always much easier to get those major snow and cold events. PS great user name , and cute dog in your avatar!

[ribster]

Hi tempestas, not suggesting a cold pattern cannot develop from the current synoptics, or indeed any pattern for that matter given sufficient time, but in the case of 2010 the overall profile farther north was somewhat different to now. Until we see the Jet pushed well south any sustained HLB looks very unlikely to me, so I think we would ultimately benefit from a sig spell of zonality, but FWIW I also think we will be looking at late Jan/Feb before this eventually happens.

I must be living in a parallel universe, it is cold and continues to be so. Even with the brief 'warm up' if it can be called that, has temps recovering to where they should be before dropping again, as demonstrated by the beeb last night. I still haven't seen the much vaunted barty or south westerlies, we were promised a while back. Edited November 25, 2013 by ribster

[Snowman.]

Latest CFS 1 month is keeping December rather blocked with very little interference from the Atlantic, cold at times but probably will feel pleasant at others.

 

http://modeles.meteociel.fr/modeles/cfs/run1m/cfs-0-264.png?00

 

http://modeles.meteociel.fr/modeles/cfs/run1m/cfs-0-450.png?00

 

http://modeles.meteociel.fr/modeles/cfs/run1m/cfs-0-552.png?00

 

http://modeles.meteociel.fr/modeles/cfs/run1m/cfs-0-702.png?00

[Frosty.]

The Gfs 06z op run shows a gradual descent into a spell of generally cold zonality with wintry ppn at times, especially on hills and more so across the north of the uk but turning rather cold at times in all areas. In the short term, this week will become a little milder and cloudier through the midweek period as moister air feeds around the top of the atlantic high which briefly drifts away further west and then a low forming across southern greenland pushes southeast to the north of scotland and we then get a short burst of arctic air flooding southeast with showers turning wintry on hills and night frosts returning, however, the atlantic high then adjusts to bring back the cloudier and slightly milder air around the top of it and down across the uk. Beyond that, the weather becomes more interesting with significantly lowering heights to the northwest swinging southeastwards with progressively colder polar air sweeping south and east with a higher risk of snow on hills, especially in the north but wet snow could fall to low levels during the heavier ppn and it will feel like winter during this period, windy and cold, possibly even stormy at times with a more southerly tracking jet, any milder weather very limited with cold air flooding southeast behind active cold fronts. This run gives a flavour of what the ecm and gem 00z would have delivered beyond T+240 hours.

[R.P. McMurphy]

I must be living in a parallel universe, it is cold and continues to be so. Even with the brief 'warm up' if it can be called that, has temps recovering to where they should be before dropping again, as demonstrated by the beeb last night. I still haven't seen the much vaunted barty or south westerlies, we were promised a while back.

 

Hi Ribster,

 

Fully agree. I think what some members forget is we can all see the charts, and see what they are currently showing. With no bias to anything as I don't really care either way (but would prefer cold and snow as that's what Winter is for!) the models to me appear to show:

 

• Cold Monday/Tuesday with Ice, Dry for most.
• Remaining cold Wednesday, Thursday, Friday, with perhaps a little rain
• Saturday to next Wednesday shows a brief warm up from current temps, with perhaps some places reaching double figures, 10-12C in the far south, still feeling chilly with cloud and sunny intervals, remaining pretty much dry for most.
• Thursday to Monday shows a big change with colder temperatures arriving, light snow for some, and perhaps heavy snow Saturday/Sunday. Temperatures minimum around -6C with daytime temperatures struggling to get above 0C especially in Northern regions.
• Monday onwards appears to carry on the theme.

Edited.

Edited November 25, 2013 by Glenn W

[johnholmes]

Is there any truth in the oft-mentioned zonal reset? In other words, are you more likely to get an evolution to significant cold from a zonal start than from the synoptics we have currently? Seems unlikely to me. 

 

none whatever in my view Yarmy, cold or mild can come from all kinds of set ups, nothing is certain to set up one or the other.