scotland Scotland Regional Discussion - Autumn 2013

[Ross B]

12Z GFS throws down the gauntlet in FI with an absolute stoater of a run:

Culminating in a proper vortex split and screaming Arctic northerly:

One of the more extreme options on the table but certainly not beyond the realms of possibility and it would deliver a hell of a lot of snow,with sub -5C uppers pretty much continously from +192 onwards.

Haha, I told you all 4 weeks ago - that's the day before I go on holiday so its bound to be snowy!!

[Buriedundersnow]

not any real change in the GEFS 18z in the short term but the mean toward 180hr has taken a slight dip with more runs looking for a colder option than the 12z which with the downward trend of the last 2 runs is another good sign and another small step for the future.

 

 

 

[Buriedundersnow]

I wonder if he is only talking about America or if this could include other places aswell

 

Ryan Maue â€@RyanMaue 3m

While we don't expect long-range forecasts to verify at all -- we look for trends in large-scale patterns that are predictable.

 

Ryan Maue â€@RyanMaue 4m

Our tools include global forecast models like GFS as well as ensembles including GEFS and ECMWF's Ensemble Prediction System.

 

Ryan Maue â€@RyanMaue 3m

Combined with analogs (historical patterns), Teleconnections (AO, NAO, MJO), 1 to 2 weeks in advance, we "could" see major anomalies coming

 

Ryan Maue â€@RyanMaue 4m

Magnitude of ensemble mean anomalies typically dampens/reduces as forecasts reach 5 then 10 days w/rather smoothed fields at Days 10-15

 

Ryan Maue â€@RyanMaue 4m

So, it's a bit impressive to see such large magnitude anomalies in a 10-day Ensemble mean hemispheric height map:

 

 

Ryan Maue â€@RyanMaue 5m

Big ridge in North Pacific & Omega block means colder period + plenty of snow coming for Pac NW & Western US in medium range. Baked in cake.

 

after the last tweet I think he was mainly talking about America but would be interested in when saying OMEGA block if he means the same as us as in Greenland

 

this was also put in as a reply to a post of his to my eye its going for slightly below average temps but maybe someone can tell me if I am right

 

http://www.metoffice.gov.uk/media/pdf/s/c/A3_plots-temp-DJF.pdf

[LomondSnowstorm]

I wonder if he is only talking about America or if this could include other places aswell

Ryan Maue â€@RyanMaue 3m

While we don't expect long-range forecasts to verify at all -- we look for trends in large-scale patterns that are predictable.

Ryan Maue â€@RyanMaue 4m

Our tools include global forecast models like GFS as well as ensembles including GEFS and ECMWF's Ensemble Prediction System.

Ryan Maue â€@RyanMaue 3m

Combined with analogs (historical patterns), Teleconnections (AO, NAO, MJO), 1 to 2 weeks in advance, we "could" see major anomalies coming

Ryan Maue â€@RyanMaue 4m

Magnitude of ensemble mean anomalies typically dampens/reduces as forecasts reach 5 then 10 days w/rather smoothed fields at Days 10-15

Ryan Maue â€@RyanMaue 4m

So, it's a bit impressive to see such large magnitude anomalies in a 10-day Ensemble mean hemispheric height map:

BZ9L9GvCEAAxi_x.png

Ryan Maue â€@RyanMaue 5m

Big ridge in North Pacific & Omega block means colder period + plenty of snow coming for Pac NW & Western US in medium range. Baked in cake.

after the last tweet I think he was mainly talking about America but would be interested in when saying OMEGA block if he means the same as us as in Greenland

this was also put in as a reply to a post of his to my eye its going for slightly below average temps but maybe someone can tell me if I am right

http://www.metoffice.gov.uk/media/pdf/s/c/A3_plots-temp-DJF.pdf

It is indeed, associated with a negative NAO.

As for the Omega block, I'd say our one wouldn't exactly be a classical omega block (yet) although with such massive amplification upstream I wouldn't be all that surprised if we did end up with the core of the blocking transfering eastwards to Greenland (at least temporarily).

Either way, that anomaly chart is an absolutely textbook example of cold zonality - core of the cold over the US, big Aleutian ridge, ridging from Iberia up to Newfoundland and low heights towards us. I reckon the margin of error is probably a bit better than with typical cold spells too, because ultimately these are hemispherically large scale features rather than just the odd shortwave or a transient icelandic block as we saw last year. The cold is sourced directly from the PV too, so that also gives us more room for manoeuvre, and any energy which does disrupt south of the trough would only act to dig the cold further south. My one concern is that heights build over central Europe, but with troughing there presently and with the dominant feature likely to be the Aleutian ridge the vortex getting squeezed to our side by D10 looks almost inevitable.

The 2m temperature anomaly drops below 5C on the 4th December for Edinburgh and doesn't get back above that for the remaining 8 days:

Edited November 26, 2013 by LomondSnowstorm

[Buriedundersnow]

the ECM ensemble anomalies map certainly paints a better picture than the op with a more blocked look around Greenland I have circled the area in the op run chart which in the anomalies chart looks to want to cut off the low pressure in the atlantic

 

Edited November 26, 2013 by Buriedundersnow

[Buriedundersnow]

good to see they temps as low as that and hopefully it comes of atleast we will start winter with a feel of it.

 

see the anomalies chart LS with the more blocked around Greenland and if you look at the op model run it is looking to try sink lows over us do u think if the anomalies chart is right with the more blocked greenland would this promote the heights to move into Greenland and the low heights to then slide into Europe.

 

or could this not happen with the PV where it is.

 

hard trying to explain bit tired. 

[blitzen]

Morning all. Still encouraging signs from the models this morning for another cold snap around the 10 day mark.  A3/4 dayer looks a possibility around the 4th or 5th which will topple again apparently, but baby steps and all that. Someone even mentioned last night that the charts have a Jan/Feb 1984 look about them! (if only)

Copied from MOD:

Some good consistency regarding the pattern change to something colder and more unsettled from GFS with the cold Northwesterly now just creeping into hi res.

 

wonderful day 10 chart although again the ridge topples later

 

 

Even so that would give a wintry few days, around a 3/4 day cold snap/spell, with plentiful snow showers even penetrating South and those in the NW who enjoy snow would be in hog heaven I suspect.

All still a fair way out though and plenty of time for upgrades and downgrades, smilies and frownies.

 

ECM appears to agree too:

 

Edited November 26, 2013 by Blitzen

[Highland Snow]

Minimum last night -3.8C at 01.30. Currently -1.1C with low cloud.

[lorenzo]

good to see they temps as low as that and hopefully it comes of atleast we will start winter with a feel of it.

see the anomalies chart LS with the more blocked around Greenland and if you look at the op model run it is looking to try sink lows over us do u think if the anomalies chart is right with the more blocked greenland would this promote the heights to move into Greenland and the low heights to then slide into Europe.

or could this not happen with the PV where it is.

hard trying to explain bit tired. 

 

Quote function has gone weird again !

 

Good to see your wrestling away with the questions Buried, anomaly charts can be deceptive, you can get predicted high latitude blocking across GEFS or ECM ens, only for nearer verification for the heights to not be as strong as forecast.  The anomaly is based against the climate norm. so can get skewed, based upon what is the background state in the anomaly plot. 

 

A good way to look at this presently is to follow the ENS against the operational on the Aleutian High, whilst it is ever present on the output, there is still inter run variability on how far it extends towards the pole.

 

Re: Dr Maue posts, Weatherbell had a lead of 10 days on the US snow storm and Arctic cold shot, I think the tweets are to back up this prediction. Joe B'Staardi has been video blogging about it for the last week or so.  One of the occasions where the ECM has verified quite well from day 10, similarly it did well at day 10 for our 'Arctic Blast'.

Edited November 26, 2013 by lorenzo

[blitzen]

Feels positively tropical here this morning at 4.3c. Just  reinforcing how chilly it has been recently. Cloudy and calm. Next 2/3 days look the same but chilly again by the weekend?

 

 

Not the most inspiring view this morning!

[blitzen]

A little interesting snippet from the Meto Contingency Planners Forecast:-

November updated Issued

 

December to February

 

Summary Temperature

 

Indications are that December will most likely be colder than average. For December-January-February as a whole uncertainty is quite large but below-average temperatures are more likely than above-average. Overall, the probability that the UK-mean temperature for December-January-February will fall into the coldest category is between 20 and 25% and the probability that it will fall into the warmest category is between 10 and 15% (the 1981-2010 probability for each of these categories is 20%).

[mistyqueen]

Oh now this is just getting ridiculous! It's effing 10.2 degrees up here! No, no, no, no, no, no, noooooooooooooo!  I'm sure it was colder in September. The murk has descended too, horrible day ahead.

[over_the_rainbow]

Minimum last night -3.8C at 01.30. Currently -1.1C with low cloud.

 

Was black ice hell walking the children to school today, and also sleety muck falling. 

[blitzen]

He He......Nice to see them disagreeing over 1984ish charts:

Paul_1978, on 26 Nov 2013 - 00:01, said:

Is it just me or are things looking similar to Jan/Feb 1984?

 

 

Gaz1985, on 26 Nov 2013 - 00:13, said:

Haha we've had so many comparisons the past 2 weeks, first it were November 2010 then December 1981 and now Jan/Feb 84

 

And your point is?

 

This period was characterised by depressions coming down from the north west over the period of a few weeks, and there were some very snowy periods in Scotland and the north of England. However I'm not sure we're far enough into the season for us to be having the same effect at the moment.

 

Looking at the models today, it just strikes me that we are seeing a similar pattern as we were then.

 

http://www.meteociel...=0&map=0&mode=0

 

The above is a good example of where you can have high pressure to the south/south west (a 'Bartlett' if you like), but still have memorable weather

 

SKEPTICAL INQUIRER:

Maybe I'm viewing the output incorrectly but I see the potential of another January 1984 developing from around the first week of December, maybe not the longevity of that spell which around these parts gave us over two weeks of cold and snow.

Edited November 26, 2013 by Blitzen

[Highland Snow]

Raining here at +1.1C. A dreich day.

[Ravelin]

Quite surprised to see reports of low temperatures this morning. I can't beat mistyqueen but at 9am it was 6C here and cloudy with light rain. It was chilly at 9pm last night when I was out for a run but I'd guestimate around 2C rather than below freezing.

 

I suppose we'll just have to endure the next couple of days until it starts to cool off again and Fridays forecast for here looks interesting. With max temps of 3-4C and a strong W/NW wind it's going to feel pretty raw.

[Highland Snow]

 

He He......Nice to see them disagreeing over 1984ish charts:

Paul_1978, on 26 Nov 2013 - 00:01, said:

 

Gaz1985, on 26 Nov 2013 - 00:13, said:

 

And your point is?

 

This period was characterised by depressions coming down from the north west over the period of a few weeks, and there were some very snowy periods in Scotland and the north of England. However I'm not sure we're far enough into the season for us to be having the same effect at the moment.

 

Looking at the models today, it just strikes me that we are seeing a similar pattern as we were then.

 

http://www.meteociel...=0&map=0&mode=0

 

The above is a good example of where you can have high pressure to the south/south west (a 'Bartlett' if you like), but still have memorable weather

 

SKEPTICAL INQUIRER:

Maybe I'm viewing the output incorrectly but I see the potential of another January 1984 developing from around the first week of December, maybe not the longevity of that spell which around these parts gave us over two weeks of cold and snow.

 

I was at University in Belfast in '84 and it was an amazing Winter - no deep cold but lots of snow so yes THAT Polar Maritime setup would do fine.

 

Very deep high latitude depressions characterised January of '84 with storms and heavy rain and then as the depressions moved east the snow showers or longer periods of snow set in behind the cold front as Arctic air was sucked southward to us.

 

Remember sitting glued to the TV and Radio 4 for weather updates and being really envious of my Kilted cousins who were getting more severe conditions than us in Ulster!

[Buriedundersnow]

 

 

Good to see your wrestling away with the questions Buried, anomaly charts can be deceptive, you can get predicted high latitude blocking across GEFS or ECM ens, only for nearer verification for the heights to not be as strong as forecast.  The anomaly is based against the climate norm. so can get skewed, based upon what is the background state in the anomaly plot. 

 

A good way to look at this presently is to follow the ENS against the operational on the Aleutian High, whilst it is ever present on the output, there is still inter run variability on how far it extends towards the pole.

 

Re: Dr Maue posts, Weatherbell had a lead of 10 days on the US snow storm and Arctic cold shot, I think the tweets are to back up this prediction. Joe B'Staardi has been video blogging about it for the last week or so.  One of the occasions where the ECM has verified quite well from day 10, similarly it did well at day 10 for our 'Arctic Blast'.

 

 

ah ok I didn't realise he might have been talking about previous stuff thought he was talking about the up and coming.

 

I understand the anomalies can fade over time but its still good to see that most of the ENS at this timescale have the atlantic looking more blocked and cut off.

 

I will keep in mind about watching the ENS for the ridge and I take it the same would apply for any ridging.

 

I think i'm trying to take too much in all at once the now might forget looking at the strat for now and stick to sorting out the understanding of the trop with just trying to learn some of the strat charts better then move on to that either later in winter or over the summer.

[Buriedundersnow]

see when it comes to the strat I wonder if I am even thinking of it right i'll try and explain how I see it a little.

 

i'm using a crazy person as the trop and a sensible hat as the strat and a punch as wave activity.

 

the way I'm thinking of it is coming into autumn the trop is a crazy person who had just put on there sensible hat and the sensible hat works from top to bottom working the sensibleness down its hat trying to reach your head to take the craziness away but before the hat can take full affect if you were to receive a punch which crazys up your head more and in turn knocks the bottom part of the sensible hat out of kilter which the top of the hat has to try and overcome and sort out but if before the hat can get itself sorted out your always open to more craziness from further punches preventing the hat from connecting the sensibleness with your head and this continues till the hat takes over which eventually it will and the only way to get rid of the sensibleness all together is by burning the hat (SSW) but till the hat takes over fully and we have the need for burning it (SSW) we are open to seeing the craziness spill over to our part of the head due to the punches being felt and not just shrugged off.

 

hope that makes sense

[Highland Snow]

One for the Geographers - which ONE Textbook would you recommend for a Masterclass on the Computer Models. I have "The Atmosphere" 9th Ed. Lutgens and Tarbuck but it is 2004 and has no material on the Models or their interpretation.

 

http://www.amazon.co.uk/The-Atmosphere-An-Introduction-Meteorology/dp/0131015672/ref=sr_1_5?ie=UTF8&qid=1385465052&sr=8-5&keywords=the+atmosphere+lutgens+and+tarbuck

Edited November 26, 2013 by Highland Snow

[Ravelin]

 

Edit: And I'm none the wiser for looking at the models and reading the MD thread this morning. All I know is that there is a wee window of wintry potential on Friday. We should look forward to this (especially the further north and west you are) and then worry about what's potentially maybe the next 1984, 1981 or any other year we wish to see repeated 

 

Yeah same here. There seems to be potential for a colder spell around the middle of next week, with the emphasis being on 'potential'. As for it looking like the same pattern as some other year, all you can say for sure is that around this time in 2019 someone will say "looks like a repeat of winter 2013/2014".

 

Edit: Since they changed the layout of the forums a day or two ago I seem to have lost the panel that allows you to do bold, italics, smileys etc in posts. Wierd!

Edited November 26, 2013 by Ravelin

[Buriedundersnow]

I'm a little bit the wiser, but regardless of that this has to be the post of the year BUS

 

Edit: And I'm none the wiser for looking at the models and reading the MD thread this morning. All I know is that there is a wee window of wintry potential on Friday. We should look forward to this (especially the further north and west you are) and then worry about what's potentially maybe the next 1984, 1981 or any other year we wish to see repeated 

 

it was the only way in my head I could work out trying to explain.

 

EDIT: HIGHLANDSNOW I don't have any idea about books i'm more of a learn as you go kind of person but i'm sure LS or LORENZO will be able to help u with what to read.

Edited November 26, 2013 by Buriedundersnow

[lorenzo]

If only....All good things..

 

 

EC32 going for HP again.

 

 

[Highland Snow]

Here is the 670 page Document on Scottish Independence published this morning "Scotland's Future: Your Guide to an Independent Scotland":

 

http://www.scotland.gov.uk/Resource/0043/00439021.pdf

 

Much as I despise Perfidious Albion I think there is strength in numbers especially in the dire economic crisis that stretches ahead further than the eye can see.

[November13]

Here is the 670 page Document on Scottish Independence published this morning "Scotland's Future: Your Guide to an Independent Scotland": http://www.scotland.gov.uk/Resource/0043/00439021.pdf Much as I despise Perfidious Albion I think there is strength in numbers especially in the dire economic crisis that stretches ahead further than the eye can see.

Aye but there is another side to that. Misery and debt in numbers. Can we not aspire to do something better than just exist. The current debt and mess reflects poorly on the UK culture and economic strategy. Edited November 26, 2013 by November13