@hd, -AO could be lot's of things for the alps, but I don't believe it would generally favour the southern side, more likely the north, east and west. Respectively.
To me the index is more likely to be negative when cold air is being pulled down from a northerly direction. There's a good example coming up, as the jet stream is disturbed, pulling cold air away from the artic and into mid lattitudes. Too far away to say where that cold will end up exactly, but the current set up favours the north and east alps, depending on how far the azores high bloats into europe.
As far as I know though, the index can be negative and europe still be under high pressure, if for example the low anomalies are in mid lattitudes elsewhere. If my understanding is wrong I would hope to learn something from another poster, regarding why it is deemed wrong / not relevent / batshit crazy.
Interesting to see todays 12z from GFS and ECM are both warm outliers, ie their averages are even colder than the main run. I think averages are useful at that 8-14 day range, especially when the Op and Control runs are at odds like GFS FI below. Sharp temp drop showing on both models, average going from about 12c to near 0 in just 2 days at 1500m.
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
@hd, @polo, my understanding was that a -NAO/AO will tend to see the jet stream pushed south with storms tracking on the southern side of the Alps. Plenty of cold air to the north of the jet stream, but likely less precipitation.
So you can end up with very cold but dry weather in the northern Alps with a -NAO/AO (although neither is guaranteed).
For lots of heavy snowfall in the northern Alps you probably want a +NAO, though that can result in rain lower down, as well as blizzards, high winds and resort closures (January 2018 had a strongly +NAO).
Conversely a -NAO can mean lots of snow and stormier weather on the southern side of the Alps which can otherwise be sheltered if a Nord Stau is piling into the northern Alps.
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
Probably a stupid question, but what type of climate trend/event is required to get lots of snow everywhere in the Alps, including lower down?
@südtirolistdeutsch, sorry about my slow response, my forecast last season was for slightly above average snowfall. I can't exactly remember if it verified well.
@twoodwar, It discusses the various factors that would lead to a -AO and -NAO setup. It generally means IMO that Europe is cold, I wouldn't say it would be very dry, but a -NAO can certainly be dry. It can depend on where the AO domain is, whether the blocking is above the Barents-Kara Sea, or north of Alaska, or Greenland, etc. I'll dig into this more in my final European outlook.
The summary would be that it concludes that the Alps would be cold and dry, resulting in a slightly below average snowfall season on average, with slightly above average snowfall to the south, based upon the sometimes curved jetstream into the Southern Alps. This is because I don't think the -NAO will be particularly dominating this winter.
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
So many if's and but's with the AO, and of course NAO. We were talking more about the former, and funnily enough, Jan 18 was actually -AO, while the NAO was positive, so can't always use them interchangeably.
Am surprised at the NOAA assertion that "during negative NAO phases, the Atlantic jet stream and storm track have a more west-to-east orientation". I have always read and observed that the jet tends to track more North-South during the brief spells of -NAO we've seen in the last few years.
Nov and Dec '17 (-AO) were very good for North, West and East alps last season. While the other -AO month was March, which was by and large good for all of the alps.
The only month last season that the Southern side did relatively better I think was February, the anomalies charts show the storm track curving up SW to NE thru the med, but that month was postive AO, and even more postive NAO than Jan was. So I don't know how the theory ties in with recent observed weather patterns, but it's all pretty loose, and even more difficult to make sense of with monthly anomalies (as opposed to daily re-analysis).
Not a great set of 00z last night, with heights once again butting in and pushing lows NE. Ops warm outliers again, but averages staying down, and control run wants to end Oct with a mini Ice Age.
Local forecasts here suggest that winter is just over a week away, which seems bonkers considering it's still warm and sunny. However those wiggly charts seem to agree! Bring it on!
Then you can post your own questions or snow reports...
Then you can post your own questions or snow reports...
Many thanks Jellybeans, I really had no idea and your guide for the ignorant is welcome
After all it is free
After all it is free
südtirolistdeutsch wrote:
Probably a stupid question, but what type of climate trend/event is required to get lots of snow everywhere in the Alps, including lower down?
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You'll get to see more forums and be part of the best ski club on the net.
12z GFS is suggesting an initial drop in temperatures Sunday into Monday more so in the eastern Alps. This may be accompanied by a few snow showers again more in Austria, before warming again in the second half of the week.
Out in FI it follows up with this on Saturday.
Which would bring much colder temperatures and more widespread snowfall, but of course that is still too far out at this stage.
Ski the Net with snowHeads
Ski the Net with snowHeads
robboj wrote:
WTF are they thinking of?
It's October, it's marketing!
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
Just came across these pictures of stubai from earlier today - anyone up for some ice hockey?
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
To be fair, the length, steepness and snowdepth of the red and blue trails in Kitz on October opening day are probably better than ~50% of the open European glaciers right now.
Kitz has gotten pretty darn good at snowfarming and storing snow over the summer. Allows Kitz to open 150-200 days a year -- about the same as somewhere much higher, like Val Thorens.
So if you're just off somewhere snowy come back and post a snow report of your own and we'll all love you very much
So if you're just off somewhere snowy come back and post a snow report of your own and we'll all love you very much
extremerob wrote:
Just came across these pictures of stubai from earlier today - anyone up for some ice hockey?
I'm surprised he even risked standing on that - if you fall on ice on a slope you are going to have trouble stopping.
One of the local racers just got back from Dachstein, which didn't look too bad, she had a low speed fall and had some very nasty bruising from the photo she published.
You know it makes sense.
You know it makes sense.
Still looking frosty at the end of Oct here. A definite pattern change on the way in the northern hemisphere, below are ECM and GFS average pressure anom's at day 10.
The Op runs themselves are still on the warm / high pressure side, so really need to see those back up west a bit to have more confidence. But JMA and GEM are better.
You can see the -AO signal (high pressure across pole, low pressure dispersed to mid lattitudes) and -NAO signal (above avg pressure around Greenland and Iceland, vs low press near Azores).
The main feature for the alps is the deep low pressure heading for Scandinavia. This will initially benefit eastern side of alps, but it could get stuck there and bring a more widespread winter spell if the high stays far enough west.
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
Hintertux doesn't look too famous either, I can see why the French team prefer the Hamburg snowdome now. That at least explains why the lift queues don't look too bad
here is the snow report from our old friends at the Tea Club, in case you were wondering:
Quote:
Hintertux Snow Conditions:The best conditions can be found on the upper slopes
Hintertux 45cm (fresh snow 30cm) Piste Conditions: Good Off Piste: Limited
Poster: A snowHead
Poster: A snowHead
^^^^^That gives me the FEAR
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
davidof wrote:
Hintertux doesn't look too famous either, I can see why the French team prefer the Hamburg snowdome now. That at least explains why the lift queues don't look too bad
here is the snow report from our old friends at the Tea Club, in case you were wondering:
Quote:
Hintertux Snow Conditions:The best conditions can be found on the upper slopes
Hintertux 45cm (fresh snow 30cm) Piste Conditions: Good Off Piste: Limited
What’s the “Tea Club”?
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
I've skied on boiler plate conditions before but that's a whole new level.
Some interesting predictions that are different from others I’ve seen.
Yes it is, but then its trying to predict the impossible. IMO depending on the exact temperature gradients that forecast could be good for the Northern Alps apart from the lowest resorts at village level.
That said I can't recall an Accuweather European winter forecast that was ever correct?
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
@nozawaonsen, seemed pretty grounded to me. Think the CFS June 19 chart and talk of onion layers was tongue in cheek. Way too many words though, to basically say, no one has a clue. Interesting bits were MF saying for western europe in particular, long term forecasts of temperature have near zero skill (due to atlantic influence). And then the scary charts showing 100+ year records broken in France and Pyrenees for warmth and dryness this year.
Elsewhere I read that this current azores blob over Europe could break local records....up to 1045mb near Ire. This is keeping most of the continent so mild and dry, but change of course on the way. ECM 12z was an improvement this am.
GFS Op and control still at odds with each other, but the average temp hovers around zero at 1500m thru month end, and northerly arm of jet looks much stronger than any southerly break away. So Scandinavia and Austria snow, but good signs still of more to come (high backing west would bring the storms to north and west side too).
So if you're just off somewhere snowy come back and post a snow report of your own and we'll all love you very much
So if you're just off somewhere snowy come back and post a snow report of your own and we'll all love you very much
@davidof, given I am taking the kids to Hintertux in Nov I am praying next weeks snow arrives!
You know it makes sense.
You know it makes sense.
polo wrote:
@nozawaonsen, seemed pretty grounded to me.
Yep, really just meant it was wittily written.
06z GFS amps up the snowfall for Austria next week.
Dumping in Sierra Nevada at the moment as forecast. Freezing level looks to rise briefly before hopefully dropping at the end of the month according to most recent GFS Op and Control runs. Fingers crossed that's the start of the base forming up high.
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
südtirolistdeutsch wrote:
What’s the relationship between the density and snow depth? Is 100kg/m^2=50cm?
Once half a meter of fresh has been pisted you are down to around 10-15cm, so the ice isn't far off but with some preparation that should be ok even with wear.
@südtirolistdeutsch, as a rule of thumb 100kg/m^2 is roughly equivalent to 100cm of snowfall, but there are a few caveats to that. Firstly it’s a very rough rule of thumb and dependent on density of the snow falling. Secondly as @davidof, points out as snow settles and is blown around the actual depth ends up being quite a bit below the amount that falls. Finally predicting precipitation is very tricky and those charts in particular (drawn from the GFS op run) are really only useful as a general guide.
Nevertheless the current snowfall forecast for Austria based on 12z GFS in the middle of next week is significant and followed up by further heavy snowfall next weekend with temperatures well below average for the time of year.
Hintertux
Last edited by You'll need to Register first of course. on Thu 18-10-18 18:38; edited 1 time in total
Then you can post your own questions or snow reports...
Then you can post your own questions or snow reports...
davidof wrote:
Once half a meter of fresh has been pisted you are down to around 10-15cm, so the ice isn't far off but with some preparation that should be ok even with wear.
You get through 10-15cm pretty quickly if you are always making turns in the same place in a race course. You will also still need to drill all the way into the ice to hold the gate so you end up sweeping away some of the fresh snow around it.
You really want more than 30cm after it has been pisted.
After all it is free
After all it is free
rjs wrote:
davidof wrote:
Once half a meter of fresh has been pisted you are down to around 10-15cm, so the ice isn't far off but with some preparation that should be ok even with wear.
You get through 10-15cm pretty quickly if you are always making turns in the same place in a race course. You will also still need to drill all the way into the ice to hold the gate so you end up sweeping away some of the fresh snow around it.
You really want more than 30cm after it has been pisted.
I agree, but we have to take what we can get. I'm hoping they'll be able to push snow around a bit up on the glacier to patch things up if there is only moderate snowfall... although nothing is on the horizon for France at the moment beyond some showers in a week's time.
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
Temperatures in the Alps are going to start falling from today. And apart from a brief rally at the end of next week look set to fall quite a bit further. Quite possibly 12 degrees below average for the time of year in just over a week.
Two sets of significant snowfall at the eastern end of the Alps in Austria look like arriving mid week (along with strong winds) and then again next weekend.
Ski the Net with snowHeads
Ski the Net with snowHeads
@nozawaonsen, dammit. Get fed up of eternal autumn with neither rain nor snow and book a trip to Scotland, and when does the snow decide to show up?! Sigh. Selfishly hoping it pushes back a day or two (I get back on the 29th).
FAQ
Poster: A snowHead
