scotland Scotland Regional Discussion - Autumn 2013

[blitzen]

 

 

EDIT: should add I don't really understand the strat and what she might be talking about might have picked it up wrong

Ha Ha...Join the club!

[Buriedundersnow]

Ha Ha...Join the club!

 

I have my own theories on the strat and how from my stand point I see it which will prob be a bit amateurish as don't fully understand it all like that EPO she was on about just learning how to try read some of the charts right.

 

 I might put it down in office over the next few days then copy and paste it in here but I don't believe the we have to look at the strat for everything and 2010 wasn't really even strat related.

 

I may be wrong but its how I see it.

[LomondSnowstorm]

I have my own theories on the strat and how from my stand point I see it which will prob be a bit amateurish as don't fully understand it all like that EPO she was on about just learning how to try read some of the charts right.

 

 I might put it down in office over the next few days then copy and paste it in here but I don't believe the we have to look at the strat for everything and 2010 wasn't really even strat related.

 

I may be wrong but its how I see it.

 

It's all broadly interlinked, is the short answer - in 2010 the very cold start was largely a product of the troposphere I believe, although helped by the fact that the strat was anomalously warm in early November, which affected a split in the vortex before it could properly set up. It's relatively rare but even this year we've seen some early 'wobbles' with the vortex from that pumped up Aleutian ridge but the cold strat in October into early November seems (so far) to have made the difference in stopping the real blocking from materialising so far. I reckon some kind of coolish zonality is the solution guided by the mid Atlantic ridge the models will eventually latch onto, with occasional greater amplification of the ridge from (as you rightly see) a promising upstream pattern will bring the odd 'proper' northerly but the problem we have is that the vortex is becoming more and more established as it should do at this time of year so I'd say our best chance of real cold is still later on in the winter when full blown strat warmings are both more common and necessary to break up the established vortex. After that it's all about the positioning of any blocking, and with the current ML blocking tending to favour the mid Atlantic there are worse places to be starting from than this (provided this holds through December, which I broadly reckon it will).

[Buriedundersnow]

probably wrong choice of words saying it wasn't strat related as there was wave activity.

 

my beef is more with people looking to what the strat is doing to see what we are going to get.

[Buriedundersnow]

It's all broadly interlinked, is the short answer - in 2010 the very cold start was largely a product of the troposphere I believe, although helped by the fact that the strat was anomalously warm in early November, which affected a split in the vortex before it could properly set up. It's relatively rare but even this year we've seen some early 'wobbles' with the vortex from that pumped up Aleutian ridge but the cold strat in October into early November seems (so far) to have made the difference in stopping the real blocking from materialising so far. I reckon some kind of coolish zonality is the solution guided by the mid Atlantic ridge the models will eventually latch onto, with occasional greater amplification of the ridge from (as you rightly see) a promising upstream pattern will bring the odd 'proper' northerly but the problem we have is that the vortex is becoming more and more established as it should do at this time of year so I'd say our best chance of real cold is still later on in the winter when full blown strat warmings are both more common and necessary to break up the established vortex. After that it's all about the positioning of any blocking, and with the current ML blocking tending to favour the mid Atlantic there are worse places to be starting from than this (provided this holds through December, which I broadly reckon it will).

 

see i do believe our best chance a long cold spell is later in winter from an SSW but i am also a firm believer that the trop could throw us a 2010 type scenario at any time no matter how cold the strat is just the more power it has now we can probably shave a few days off any cold as the vortex will recover slightly quicker.

 

and i also believe that 2010 might have been rare as it may have been a response to the solar argument and till we rule that out we can always have a chance of seeing more periods like this.

[LomondSnowstorm]

probably wrong choice of words saying it wasn't strat related as there was wave activity.

 

my beef is more with people looking to what the strat is doing to see what we are going to get.

It's a fair point - we do need to look more holistically at the entire system and how it interacts rather than just looking at a relatively small part of it. When we talk about the stratosphere being important what we mean is more how it interacts with the troposphere and the rest of the global circulation system. And even then trying to work out how it affects our little bit of land is even more of a crapshoot and depends on a plethora of contradictory factors, all of which are linked to each other one way or another. Which is part of the reason we built computer models to try and work out the details and stop all our brains from exploding

Edited November 24, 2013 by LomondSnowstorm

[Buriedundersnow]

where do u find out how warm the strat was through the month as all i am looking at is the berlin site and it just says that November and December had cold monthly means.

[Northernlights]

-3c now and clear starry sky. Might not be snowing but winter has certainly arrived this month.

[Buriedundersnow]

It's a fair point - we do need to look more holistically at the entire system and how it interacts rather than just looking at a relatively small part of it. When we talk about the stratosphere being important what we mean is more how it interacts with the troposphere and the rest of the global circulation system. And even then trying to work out how it affects our little bit of land is even more of a crapshoot and depends on a plethora of contradictory factors, all of which are linked to each other one way or another. Which is part of the reason we built computer models to try and work out the details and stop all our brains from exploding

 

yeah i'm trying to learn some of it and its a lot to take in.

 

i'm more going off what people have posted in the threads since i joined where people said that 2010 was pulled in by the models and the strat models then last winter there were posts saying the strat is screaming for heights over Greenland and nothing happened and i feel that has made a lot of people think that what the strat charts show is what will happen and i think that might be wrong as who is to say that the trop modelling didn't pull in the strat model as it picked up the pattern early and that's why the strat model pulled it in cos surely theres a chance of the trop model leading the strat model.

 

if that makes sense.

 

EDIT: like just because the strat charts aren't showing anything surely doesn't mean that the trop cant throw us something and the strat charts can change there outlook where as i feel theres a lot of if theres nothing in the strat charts we aren't going to see anything.

 

surely theres every chance the trop could show something and the strat doesn't pick it up for a day or two or is there no chance of that happening.

Edited November 24, 2013 by Buriedundersnow

[LomondSnowstorm]

where do u find out how warm the strat was through the month as all i am looking at is the berlin site and it just says that November and December had cold monthly means.

 

This is decent, gives the temperature anomalies, wave activity and 'z' values (basically the heights i.e. high z values mean blocking, low means troughing essentially) right up through the atmosphere all the way back to 1979:

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/

This is the 30hpa temperature graph for 65-90 degrees north, showing the warm strat early November 2010:

You can get the rest of these from this link here:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/

 

RE last winter, the blocking did occur hemispherically on an impressive scale, but lowland Scotland was pretty unlucky locally for most of January/February, and then March was the coldest month of the lot!

[Buriedundersnow]

This is decent, gives the temperature anomalies, wave activity and 'z' values (basically the heights i.e. high z values mean blocking, low means troughing essentially) right up through the atmosphere all the way back to 1979:

http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/

This is the 30hpa temperature graph for 65-90 degrees north, showing the warm strat early November 2010:

You can get the rest of these from this link here:

http://www.cpc.ncep.noaa.gov/products/stratosphere/temperature/

 

RE last winter, the blocking did occur hemispherically on an impressive scale, but lowland Scotland was pretty unlucky locally for most of January/February, and then March was the coldest month of the lot!

 

cheers LS will save they sites and have a look through them.

[NorthernRab]

-5'C here now, coldest temperature of the winter autumn thus far! 

[Buriedundersnow]

 

RE last winter, the blocking did occur hemispherically on an impressive scale, but lowland Scotland was pretty unlucky locally for most of January/February, and then March was the coldest month of the lot!

 

 

the posts I was on about last winter calling for heights over Greenland were during December in the fail where we were being told to watch for the high to retrogress to Greenland and it never and a couple of other times we were told the strat charts were calling or heights there and it didn't happen either.

 

EDIT: should add that was posts in the model thread not in here.

Edited November 24, 2013 by Buriedundersnow

[lorenzo]

What you find BUS is that when the NWP has a less than impressive outlook, folks tend to visit the strat thread to see if there are any changes in the post that will alter things. 

 

Re Troposphere vs Stratosphere. This excellent post from Chiono is a great visual description of what happens that addresses some of your thoughts from last evening.

 

http://forum.netweather.tv/topic/78161-stratosphere-temperature-watch-20132014/page-3#entry2809151

 

Beautiful clear morning, a nice crunch underfoot, hopefully more days like this to follow and we manage to get a view of ISON in the next couple of weeks should it survive Perihelion.

 

Looks nailded on Catch

 

Today, looking out for the latest CPC MJO update later on, will be interesting to see what this is due to be up to later in the month..

[Scottish-Irish Skier]

Hard frost the morn. Was -4.7 °C about an hour ago. -4.5 °C now.

[lorenzo]

Mentioned ISON earlier, good thread and within it a post on viewing the comet here

[mistyqueen]

Morning all! Temp got down to 0.6 last night so not quite up to cold winter standard yet. Calm and cloudy again today. Liking the look of that last chart Lorenzo! Be honest...d'you really think that'll ever come off?

Edited November 25, 2013 by mistyqueen

[Cheggers]

Brrr, -3 and a dense fog up here in the wilds of Denny.

[lorenzo]

Morning all! Temp got down to 0.6 last night so not quite up to cold winter standard yet. Calm and cloudy again today. Liking the look of that last chart Lorenzo! Be honest...d'you really think that'll ever come off?

 

Thanks for asking Misty, gives me a chance to dig this one out, one of my best Winter memories. Was at a football match with my Dad, and it got abandoned at half time, couldn't make it home, ended up staying at a friends as the roads were completely drifted out.

Not identical , but for our location shows the evolution is not impossible. At present, I would say unlikely in terms of December 2013, we can only hope !!

[Highland Snow]

Tanked out at -5.8C the coldest yet.

[Ravelin]

Bright start to the day here again after a weekend that was less so. Some earlier light broken cloud has cleared and it's sunny with virtually no wind. At around 9am the temps were -3C in Kemnay and -1C in Dyce so a frosty start too.

 

Weather for the coming week looks rather unexciting. Cool/cold today before a milder blip Tue/Wed then cooling down again. Probably not much in the way of sun, or rain for here at least.

[Poots]

Another bright morning here. Was quite foggy at 6am and temp is sitting only at -4.5 here just now. Brrr!

[NUT]

Another really quite misty and foggy morning (frosty too) lifting now though

[lorenzo]

Gotta love the GFS 06z, if weather models were animals it really would be a daft auld dug.

 

It must know we are suffering from anti-cyclonic model blindness.

 

Throws in a trademark Uber Low

 

 

 

Anyone seen the 06z verify from 11.5 days out ??

 

Wouldn't trust it at 11.5 hrs

 

486dam air approaching the NWest of the Country. LOL !!

Edited November 25, 2013 by lorenzo

[Ravelin]

^^^

Oh go on, for once verify just for a laugh, and to see the reaction on the model thread as it does.