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Zenarcher

Scotland Regional Discussion - Sunday 20th >>

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Please continue to discuss the Scottish weather :)

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No then ,, everybody still in there scratcher lol

South of England getting hammered

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Snow flurries continue for me this morning but not amounting to anything other than a very light covering on the grass and the smallest ever drifts. As for tomorrows snow chances - its still on. After midnight the snow should reach the Scottish Borders and continue moving up the east coast. The main issue on this occasion will be marginality but if it can stay as snow it could get quite interesting as we go though tomorrow with relatively strong winds and some blowing snow especially on high ground. The snow is likely to affect a wider area and the wind direction would indicate that conditions across the Central Belt could get tricky (obviously all the caveats such as luck apply). I would think that the Met Office may extend the warning areas today and an amber may pop up for some.

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Looks like many parts of the coastal strip will get wet rather than white tomorrow, according to the Met Office...

"Strong winds and snow affecting eastern Scotland and northeast England, although rain and sleet near eastern coasts. Rain, sleet and snow also affecting some southwestern parts. Fine elsewhere. Generally cold."

http://www.metoffice.gov.uk/weather/uk/uk_forecast_weather.html

Inland with a bit of elevation could be a different matter though?

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Morning - still held onto the snow that fell last night. Hoping that the marginality issues don't affect the coast too much today :).

Sky this morning looks very promising for a wee flurry.

The chickens are refusing to come out - is this a sign? Chicken forecast for today.

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How marginal is it here, as in a Se'ly Embra isn't on the coast as it were, what do the uppers, DPs look like?

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Bit of a snow-pellet whiteout in Stirling just now - bitter cold....

Just seen the forecast on the beeb. It's all about the snow in the SE dontchaknow.

fool.gif

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Morning - still held onto the snow that fell last night. Hoping that the marginality issues don't affect the coast too much today smile.png.

Sky this morning looks very promising for a wee flurry.

The chickens are refusing to come out - is this a sign? Chicken forecast for today.

morning all

after these last few days I'd tend to agree...but I can't help torturing myself and have we my hopes up! how does it compare to.last Monday? I walked to work in pouring rain that day, no hint of sleet or snow. by later on in the day it turned to snow, even down the docks.

edit- apologies snowy owl, was meant to quote the doc.

weather ttoday looks cold. been some wee flurries overnight.

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0.4c/-3.2c/E. Had a few light graupel? showers this morning falling onto a frozen surface. Something not quite right here so far. We appear to have had plenty falling but not really accumulating? Going to be really interesting overnight/Monday I think as to who gets what and where!

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Just checking the radar as well - the MetO didnt forecast the band coming into the SE until later on today, but checking radar, it's already hitting the shires - clearly moving faster than progged...this I assume, is what we are expecting later on.

edit - interesting as well - the 528dam straddles the central belt tomorrow at 0900...interesting times ahead..

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morning all

after these last few days I'd tend to agree...but I can't help torturing myself and have we my hopes up! how does it compare to.last Monday? I walked to work in pouring rain that day, no hint of sleet or snow. by later on in the day it turned to snow, even down the docks.

edit- apologies snowy owl, was meant to quote the doc.

weather ttoday looks cold. been some wee flurries overnight.

To be honest tomorrow it is very marginal for some eastern parts, more especially around E Fife for example http://expert-images.weatheronline.co.uk/daten/proficharts/en/nae/2013/01/20/basis06/ukuk/prty/13012106_2006.gif

I am not convinced that we will get the proper precipitation until later, based on the NAE data http://expert-images.weatheronline.co.uk/daten/proficharts/en/nae/2013/01/20/basis06/ukuk/prty/13012112_2006.gif

It looks like once again the Borders and inland areas up here could do well, and quite probable some Central Belt areas which have largely missed out so far. Lots for NE England too.

Overall, I am not holding my breath but would love a pleasant surprise.

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I was very lucky to get a kindle fire for chronic. it's great, does all the iPad stuff too like browsing and apps. I'm used to the iPad tho and kindle in cc comparison is . bit rubbish at the other stuff. does the job tho. I also just had a minor panic after dropping it. repeated turn ons but no joy and blank screen...until I realised I was holding it the wrong way round and looking at the back. ah dear, the years may be catching up with me.

what am I rambling about- apologies off topic nonsense,

edit - chronic? that was meant to say Christmas. hard to type on them to!

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south of england -14 tomorrow morning at 6am rofl.gif they will grind to a halt... few boiler failures me thinks

13012106_2000.gif

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Just checking the radar as well - the MetO didnt forecast the band coming into the SE until later on today, but checking radar, it's already hitting the shires - clearly moving faster than progged...this I assume, is what we are expecting later on.

edit - interesting as well - the 528dam straddles the central belt tomorrow at 0900...interesting times ahead..

At the rate it's going it will be here early evening. Can only assume that it will slow as it moves North.

Ochils did well last night, as it was a bit patchy yesterday on lower slopes, but all white now. Not a lot here, still just a dusting.

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At the rate it's going it will be here early evening. Can only assume that it will slow as it moves North.

Ochils did well last night, as it was a bit patchy yesterday on lower slopes, but all white now. Not a lot here, still just a dusting.

As long as it hits us "after dark", I aint too fussed :p

I'm going to turn into a vampire at this rate ....

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How marginal is it here, as in a Se'ly Embra isn't on the coast as it were, what do the uppers, DPs look like?

dew point ok13012109_2006.gif

13012109_2006.gif

uppers probably ok

13012109_2000.gif

2m temp could be doing with being a degree or so cooler but as long as uppers and dew stay well on the favourable side then hopefully ok

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Morning, hovering around 0c here this morning and no snow lost. Slight flurry has covered the clear path overnight, but nothing to shout about. Will be interesting to see how quickly the band in the SE is moving and how quickly it arrives with us, perhaps I'll see some action tonight!

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Most seem happy so far in the South East? Some saying that it is the dry powdery type which is falling. Still showery here as every now and then I here it hitting the conservatory roof and thinking it is rain. No panic tho' it's hail. Must be warmer air aloft then?

That front down south is really motoring is it not?

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Very lightest of snow flurries here.

-1.1 C, DP = -2.2 C.

Couple of extra cms from yesterday evening/overnight.

Tomorrow morning could be interesting.

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Good morning temp currently -0.2/-4.0

I really hope we all get some Snow from this front later today/tommorow, But I wish we could just have a snow event without worrying all time about the temperture :(

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That front down south is really motoring is it not?

Aye, reports coming from Northampton already.

North Sea still churning showers out.

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'mon oor snaw

No !!!

Slow Down...slow down....

edit - When's Mondy being reincarnated ?

edit edit - this is becoming a bugbear now - Thomas Shavanananananazkaky has just delivered his latest ponderings, and, at no point in it, did he make use of the word "Scotland". "Northern UK" blah. I may be being overly sensitive, but my "YES" vote is gradually gathering momentum.

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    • By LomondSnowstorm
      Well here we are again folks, that special time of year when the anticipation of Christmas is matched only by the joy of the now annual tradition of the LomondSnowstorm winter forecast. Last winter promised much and delivered some, although on the ground it was generally more of a slushy hinterland than a winter wonderland. So can we continue the trend of generally below average winters which have developed in tandem with a more southerly tracking jet, or will the glorious summer of 2013 usher in another trend bucking warmer than average season? In this forecast I’m going to look at a number of factors, including the El Nino Southern Oscillation, Global Angular Momentum, the Quasi Biennial Oscillation, Arctic Sea Ice, Eurasian snow extent/autumnal gain and Solar Activity to put together a forecast for what the winter of 2013/14 has in store for us. Once again, the usual disclaimer goes out about the low confidence nature of the more detailed parts of the forecast, but it’s good fun and paints a picture more readily for those who don’t have a particularly strong meteorological background.
      [size=6][b]ENSO[/b][/size]
      The El Nino/La Nina state, an index of the Sea Surface Temperature anomaly in the Eastern Pacific, has been shown to be critical to the global circulation pattern, so I’ll address if first. At present, as it has been for about a year now, we’re in a neutral phase (between 0.5 and -0.5 amplitude), and the model outlook suggests that it will stay that way throughout the winter:
      [attachment=191357:enso.jpg]


      Neutral ENSO winters have been shown to have SSWs less frequently than in those with either a clear La Nina or El Nino state (Butler and Polvani, 2011) which would indicate a lower chance of Polar vortex disruption and therefore a higher chance of more ‘normal’ winter conditions than we saw last year. However, neutral/weak ENSO values are also associated with a greater frequency of –ve NAO conditions, which is strongly correlated with below average temperatures.
      [size=6][b]QBO[/b][/size]
      The Quasi Biennial Oscillation is another key factor to consider, with easterly (negative)QBOs encouraging a weakening of the Polar Vortex and westerly QBOs a strengthening. However, it is more complex than that, and a combination of a Westerly QBO and a peak in Solar activity has been shown to increase the probability of a Sudden Stratospheric Warming Event. Currently, the QBO is in a Westerly state and will remain so (given that it’s a two year cycle) for the rest of the winter:
      [attachment=191369:QBO.jpg]
      [size=6][b]Solar Activity[/b][/size]
      This is one of the hottest (if you’ll pardon the pun) areas of meteorological research at the moment, and along with the Stratospheric developments this has contributed a huge amount to the advancement of medium range forecasting in recent years. The interest began when the historically cold winter of 2009/10 occurred during a deeper and more prolonged sunspot minimum than we’ve seen in 100 years:
      [attachment=191377:sunspot.jpg]
      The inevitable upturn in the 11 year cycle has taken place since then which takes us up to near the peak of the cycle this winter, although it’s a peak which is far more akin to those of the freezing Dalton minimum years than those of more recent years, . Nonetheless, remember the linkage between Solar Activity, West QBO and an increased prevalence in SSWs, because it may be critical to the coming winter.
      [size=6][b]Arctic Sea Ice Extent[/b][/size]
      For the unitiated this one might seem a bit strange, but in fact there is a reasonably strong basis for [i]lower [/i]Sea Ice extent being associated with an increase in the prevalence of blocking highs and a subsequent decrease in average temperatures across western Europe. As anyone who pays much attention to environmental news knows, Sea Ice in the Northern Hemisphere has been at historical (at least during the post 1979 satellite age) lows in extent. However, this year has seen something of a comeback for the ice, with the extent so far for the year being the highest since 2006:
      [attachment=191371:sea ice.jpg]
      Still, it remains below the long term average so this can be tallied up as being a slight mark in favour of increased blocking. October [size=6][b]Eurasian Snow Cover/Snow Gain[/b][/size]
      This one makes perhaps more sense, although again perhaps not for the reasons you’d imagine – increased snow cover in October and November across the Eurasian continent causes low ground temperatures which leads to stagnant rising air and hence high pressure systems to form across high latitudes, which leads to a weakening of the vortex from below and the displacement of cold air southwards to our latitudes. After an exceptional end to September for snow gain, the uptake since then has been less spectacular, with the ‘Snow Advance Index’ for October being somewhat below the long term average, although we’re still sitting hemispherically at above average once again thanks to recent gains in the Eastern US.
      [attachment=191373:Snow cover.jpg][attachment=191372:snow cover 2.jpg]
      Overall then this index is neutral, with the gain being far less spectacular than it could have been but partly because of a record high starting point.
      [size=6][b]North Atlantic SSTs[/b][/size]
      The feedback between Sea Surface Temperatures in the North Atlantic and the North Atlantic Oscillation, or in other words blocking over our side of the Northern Hemisphere, was shown to have been largely responsible for the record cold December of 2010 (Met Office, 2013). The key signature of a negative NAO is a tripole in the North Atlantic, with a cold section around 30-50 degrees latitude just off the coast of Eastern Canada, with warmer sections to the north and south:
      [attachment=191376:SST correlation.jpg]
      The signal is rather muted but a tripole of sorts has been showing in the North Atlantic in recent weeks, which is a fairly promising sign, although we need to watch to see if this sustains and develops further.
      [attachment=191375:SST 2014.jpg]
      [size=6][b]Arctic Oscillation tendency[/b][/size]
      Two recently developed indices of snow cover and height anomalies respectively have an exceptional record of predicting the Arctic Oscillation tendency - Cohen’s Snow Advance Index, which as previously discussed is indicative of a moderately positive Arctic Oscillation, and the very recently developed October Pattern Index, which can be thought of as the atmospheric effect of the SAI, which is actually at its highest value since 1991/92. Anyway, given the agreement between the two and the high predictability both have, I’d put our chances of seeing a +ve Arctic Oscillation for the winter at 90% plus. This doesn’t necessarily preclude a below average winter, and is less reflective of temperatures at our side of the pond than the North Atlantic Oscillation, but hemispherically it points towards high latitude blocking being generally scarce and does reduce our likelihood of a cold winter. However, this does not imply a permanently positive Arctic Oscillation, and we should bear this in mind.
      [size=6][b]Long Range Forecast models[/b][/size]
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      [size=6][b]Global Angular Momentum[/b][/size]
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      [size=6][b]Composites[/b][/size]
      Having looked at years from 1958 onwards (prior to that the datasets become sketchier and it’s tougher to pattern match) and basing on the criteria outlined above I’ve come up with 11 composite winters which broadly match the likely winter ahead. These were all either ENSO neutral or weakly positive/negative (value less than 1), featured positive QBOs and are ‘weighted’ towards those which are more similar. While some years with negative Arctic Oscillations were counted, years were double weighted based on the Arctic Oscillation value given the likelihood of a positive one this year. The most similar winter was 1990/1991, which is counted four times in the composite charts, with 1971/72, 1980/81, 2001/02 and 2008/09 counted twice and the rest just once. The full list of years are:
      2008/09, 2001/02, 1990/91, 1985/86, 1980/81, 1978/79, 1971/72 ,1966/67, 1961/62 and 1959/60.
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      [attachment=191365:December height.jpg]
      For December, the Aleutian Ridge and negative height anomalies over the Western side of the Arctic are the most notable features, but otherwise the anomalies are fairly muted, with a positive anomaly out in the mid Atlantic and actually a slight mean trough over Europe.Half of these winters featured either a Canadian Warming or SSW in the first half of winter, with 8/10 featuring a notably cold stratosphere initially, so this may well be the key to our winter once again. The Stratosphere composite looks like this for December:
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      [attachment=191364:Dec the strat.jpg]
      [size=5][b]January[/b][/size]
      Onto January and we have a very different looking anomaly – Greenlandic height rises come into play but with a very strong negative height anomaly stretching right across from NE Canada into southern Europe. Again, this is very far from clearcut, with evidence of some vortex disruption particularly in our neck of the woods but still with negative or neutral height anomalies across the pole:
      [attachment=191368:Jan the strat.png]
      A look at the stratospheric picture once again may help to enlighten us further – the stratospheric vortex looks to end up split over the North American and Siberian sectors with a mean strat. ‘ridge’ over Europe and the Atlantic:
      [attachment=191367:jan strat.jpg]
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      [size=5][b]February[/b][/size]
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      [attachment=191366:feb height.jpg]
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      [attachment=191370:r2Udu38dtx.png]
      [b]Adjustments[/b]
      Given the SST pattern I’d suggest that the mean height anomaly for February is centred somewhat further west over Greenland, while low heights south of 60 degrees north are likely to be confined to southeast Europe through December.

      [size=7][b]2013/14 Winter Forecast[/b][/size]
      [b][size=5]December[/size][/b]
      A very zonal period to start the month following a short, sharp Arctic blast at the end of November, with west-northwesterly winds and very limited blocking. Near constant low pressure systems will bring wind and rain throughout, with only brief drier interludes. Temperatures above average in England and Wales but near or even slightly below average for Scotland, where colder upper air temperatures will bring the odd smattering of snow even to lower levels in spite of a lack of frost, with precipitation above average initially everywhere. Perhaps something along the lines of this:

      From around the 12[sup]th[/sup] onwards things will quieten down, with high pressure building in from the south, bringing a brief spell of very mild southerlies followed by a dry and eventually frosty spell in the run up to Christmas. Temperatures above average everywhere up to the 20[sup]th[/sup] but cooling down towards average from the south as heights transfer northwards, precipitation generally below average away from the far northwest Highlands where they’ll be around average. By Christmas, heights will transfer westwards with an initial spell of rain followed by a genuinely cold northerly blast as low heights dive temporary southeastwards, bringing more widespread snowfall and low temperatures, although with accumulation generally confined to the usual spots (which of course vary depending on the exact wind direction) before the dam breaks and the heights sink once more by month’s end. Temperatures will be generally above average for most of England and Wales, with an initial CET punt of 5.6C, the Scottish mean will sit around average at 3.4C. Precipitation will be marginally above average for all of Scotland and much of northwest England but for southern England and Ireland it will be around or below average. In other words, a fairly typical December.
      [size=5][b]January[/b][/size]
      I’m anticipating a switch around in January, where transient colder snaps brought about by an excessively strong vortex are replaced by a more wintry pattern. Nonetheless, it won’t start off that way – more bog standard Atlantic frontal systems will dominate the first half, with temperatures and precipitation widely above average. However, as the month progresses, mid latitude height rises will ridge northwards, with the jet finally being diverted southwards with colder air encroaching from the east. With still a large chunk of the vortex situated over Canada the height rises will take a week or two to become properly established, with a number of transitional snow-rain-snow events interspersed with more settled milder days, and temperatures will generally be around or slightly below average, but eventually, by around the 25[sup]th[/sup], a cold easterly flow will be established, ushering in one of the main cold spells of the winter. With the centre of the high between Iceland and Scandinavia rather than further east and with still a fairly impressive cold pool over the Arctic the UK could tap into some severely cold uppers if the setup works out. This would bring a period of very low maxima, perhaps sub zero, with the potential for significant snowfall right across the British Isles, but particularly for areas exposed to the easterly wind (including the Forth-Clyde streamer area) where showers would merge into longer periods of snow, although with low heights anywhere in the south of England could see some impressive snowfall totals, perhaps upwards of 8 inches quite widely IF we tap into the cold pool before the flow is cut off. (Note: the timing and severity of this event are very much low confidence, so I’d wait until at least early January before stocking up on tinned goods). Temperatures for the month as a whole will be below average but not massively so – a CET of 3.1C and a Scottish mean of 1.8C are my current bets. Precipitation totals generally around average, with the exception of the Western Isles and Northwest Highlands where it will be somewhat drier than average and southern England where it will be above.
      [size=5][b]February[/b][/size]
      With the easterly flow cut off by the start of the month as heights lower from the north a brief spell of anticyclonic weather will prevail through the first part of February, away from the far south of England where the odd snow shower may remain. Temperatures at the surface would be well below average even without the upper cold pool as the snow fields caused minima to drop like a stone under clear skies. With the southerly arm of the jet still dominant, and the vortex still not really managing to get a foothold east of Canada, a reload of the cold looks likely, with a weak Scandi trough/ weakfish southeast Greenland high providing a possible route, propped up by the strong southerly jet. This would give more snow to eastern parts, with Aberdeenshire in particular taking a bad hit, and temperatures way below average once again. By mid-month the pattern will look to shift westwards, with height rises over Western Greenland, leaving us in a west based –NAO state (think February 2010) with a rather messy cold trough, bringing a rather dour mix of snow, sleet and cold rain from a variety of wind vectors before eventually height rises over southeastern Europe build northwestwards and introduce a milder flow to end the month.
      Precipitation once again above average, although moreso in eastern parts, with temperatures very much suppressed until the very end. My CET punt is a very cold 0.8C, the coldest February since the sub zero 1986 (one of the ‘lesser’ composite years incidentally) with the Scottish mean a positively balmy 1C.
      I hope I haven’t bored/scared you too much, and I’ll be looking to update it throughout the winter and give an honest assessment of if/when it goes completely bust and we end up with a heatwave early February. I’ll be updating this in the next few days too with one or two synoptic charts which maybe give a better representation of my thoughts than the description does.
    • By onemanmows
      View over the carse towards Mentieth Hills and Aberfoyle
    • By lorenzo
      A new thread for a hopefully snowier outlook as Friday evening progresses... As always if you look in on the thread and haven't posted, please say Hello, we are a nice friendly bunch. Previous Thread here
      Good Luck Folks !
      Here are a couple of images from the NetWeather Radar for this evening show the developing picture well and whet the appetite.
      First image is standard precipitation overlay, social media overlay, wind chill and scale.
      Second image shows weather type and dewpoints.
      Hopefully you can see the other icons for selection on the right hand side of these images.

      Yours for one month for the cost of 349p, goes well with lamp posts.
    • By Angelici Magiovinium
      Please use this thread for your regional discussions about the current weather or what is being forecast for the next few days in Scotland....
      link to the previous one here...
      http://forum.netweat...3/page__st__720
    • By Angelici Magiovinium
      Please use this thread for your regional discussions about the current weather or what is being forecast for the next few days in Scotland
      Link to the previous one here…
      http://forum.netweather.tv/topic/75517-scotland-regional-discussion-january-12th-2013/page__st__820
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