 Poster: A snowHead
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rob@rar, thanks for the info...
Still, i might have to start praying to the snow-gods before i go to bed 
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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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?
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rob@rar, LOL - I was about to say get to the end of the queue!
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You need to Login to know who's really who.
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Well, I got back last night, and obviously can't see the glacier. However the snow level on the mountains to the South is much, much lower than last year. Last year it still looked like summer on La Muzelle, and there's snow (not skiable obviously) down to the bottom of the eye now. I'll take a photo and post it later. I'll be up on the glacier tomorrow, so will take photos and post a proper report.
I heard that there was torrential rain on Monday/Tuesday and that Austria had it so bad that they've cancelled the WC races in solden.
Ray Zorro can always ski the mud and stones back to resort, but not on Jutta's skis please. 
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brian
brian
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You'll need to Register first of course.
You'll need to Register first of course.
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| rob@rar wrote: |
| GFS forecast has temperatures dropping down to seasonal norms around the 4th November. Let's hope they stay there, or get lower... |
Watch our for middle of next week now. Looks to be good (at least higher up) before the 4th now. Reasonable agreement from all three "main" models, but the details will probably change.
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skanky, excellent news - today's 06z GFS run looks much nicer than 00z.
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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.
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| rob@rar wrote: |
| skanky, excellent news - today's 06z GFS run looks much nicer than 00z. |
My Babelfish is still on the blink....
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eng_ch, translation for us PSBers = good chance of WooHoo!!!!
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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| eng_ch wrote: |
| rob@rar wrote: |
| skanky, excellent news - today's 06z GFS run looks much nicer than 00z. |
My Babelfish is still on the blink.... |
Sorry. Bablelfish might have translated it like this: "The 6am forecast by the GFS service was much better than the 12am forecast if you are looking for cold weather across the Alps. The colder weather which was forecast to arrive around the 4th November now looks like it might arrive a bit earlier (1st Nov) and there was closer agreement on this colder weather between the slightly different forecast models which are used each time they do a main forecast run. The forecast looks like this 
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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.
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FenlandSkier, kewl 
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You know it makes sense.
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rob@rar, thanks, I'm a bear of little brain  So let me see if I understand the charts better now – atm it's looking like temps will dip back below seasonal average for a few days at the end of next week with a chance of some light precipitation around Wed, and then the next couple of weeks hovering around seasonal average with more chance of precipiation in about a fortnight? And teh control run is looking more optimistic for us than the cumulation of teh runs?
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brian
brian
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rob@rar, bit dry though. PSB in Slovenia anyone ? 
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Poster: A snowHead
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eng_ch, yes, I think that's right, but I'm very much an amateur on this so others such as skanky or brian might be along to correct us! Don't forget that the GFS model is only one of a small number of forecast models, and there seems to normally be some variation between them especially for the longer range (> 5 or 6 days) forecasts. Also, as you can see in the graph above (which will update automatically) there's not a lot of agreement between the slightly different scenarios that GFS runs each time it does a forecast, so anything beyond about 1 November should be taken with caution.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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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?
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rob@rar, oh and thze Google Babelfish couldn't have put it as articulately as that
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You need to Login to know who's really who.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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Frosty the Snowman, excellent! How much you bunging them for that? 
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brian
brian
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brian, nice, thanks for that.
I was looking at the GFS 12Z run when I posted above. There isn't a huge amount of snow to be expected (but that's as much down to the time of year), but it's an improvement on warmth and rain.
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Frosty the Snowman, perfect timing 
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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.
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Excellent, thanks. How far out are ECM data available?
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| rob@rar wrote: |
| Excellent, thanks. How far out are ECM data available? |
Doh! Just spotted: 168h.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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rob@rar - I like the graph - but do you have any idea what the various colour lines mean?
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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.
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Yes, a vague idea. Top group of lines is temperature, bottom set is precipitation. Within the top set the thick red line is the seasonal average. The other lines are all forecast data, with slightly different variables. These are all forecast at the same time, but the variation in some of the criteria for the forecast account for the possible differences betwwen these lines. The slightly ticker white line is the average of this ensemble forecast. When all the ensemble lines are close together there is high confidence about the forecast, but obviously when there is a lot of divergence there is less confidence. The blue line is the control line - someone else, skanky or brian perhaps, will have to explain that. The temperature is the forecast for the 850mb point (approx 1500m, subject to some atmospheric variation).
The bottom set of lines is the same principle of an ensemble forecast for precipitation. White line is the average, and obviosly a red line for seasonal average would be fairly meaningless, so it isn't included.
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If I'm reading it right, the chart is getting even more promising?
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You know it makes sense.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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eng_ch, there is less spread in the ensemble, so there is more confidence in the forecast that temperatures will begin to fall from about the 29th, dipping below the seasonal average around the 2nd November. After that date it's a bit early to say what the trend might be. There looks like the possibility of a light dusting of snow around 2 November, but not enough to make a significant difference to ski conditions I'd say. A couple of caveats: the graph above is the forecast for the Geneva region, so it might be different further south; this graph is based on only one set of meteo data (GFS) other data sets and models which might show a different forecast.
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Poster: A snowHead
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eng_ch, yes, I think so. NOt looked at the other models yet though.
rob@rar, I used to think that the blue line was the operational run, but I'm not totally sure. Anyway, at the site that brian posted, you can see all the different GFS ensemble runs as charts so you can see the synoptic differences that give each line. Which is interesting. Also, one point that's worth noting, even if all the ensembles are in tight agreement, if none of the other models are the confidence can be considered a bit lower (different models have their own biases which can adversely affect things in crtain set-ups). One point to note is that sometimes the operational run may be an "outlier" eg it may disagree with most of the other runs, in which case it's best to take most of it with a pinch of salt.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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rob@rar, even the unreliable meteoschweiz is predicting an 8-10 degree temp drop after today
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brian
brian
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.... and that even with excellent model agreement and ensemble agreement it can still all turn round a few days out, as happened with the forecast Scottish NE'ly a couple of weeks back.
I would say beyond a week is no more than "of interest", ie. look for developing trends, 4-7 days is "could be hopeful" and less than 4 days is probably "worth getting excited about".
The thick blue line used to represent the operational run but they changed that this year for some reason. I think the operational is no longer shown in the ensemble chart and Wetterzentrale just haven't updated to reflect that.
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You need to Login to know who's really who.
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skanky, is that Meteociel site that brian posted the best place to view other models. I've been looking at it this morning and it shows GFS, UKMO, ECMWF and JMA (Japanese?). If I want to compare differences between the models where is the best place to look?
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| brian wrote: |
I would say beyond a week is no more than "of interest", ie. look for developing trends, 4-7 days is "could be hopeful" and less than 4 days is probably "worth getting excited about".
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This is the most important caveat!
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brian
brian
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| Quote: |
| If I want to compare differences between the models where is the best place to look? |
Wetterzentrale has more models (inc GEM and NOGAPS which are both okay). Yes JMA is Japanese. Otherwise it's personal preference.
| Quote: |
| I would say beyond a week is no more than "of interest", ie. look for developing trends, 4-7 days is "could be hopeful" and less than 4 days is probably "worth getting excited about". |
I tend to use the FAX charts as my range of confidence (though they tend to be just representations of the UKMO, they can be modfied to other model guidance if the forecasters think it necessary. I don't just go by FAX though).
| Quote: |
| .... and that even with excellent model agreement and ensemble agreement it can still all turn round a few days out, as happened with the forecast Scottish NE'ly a couple of weeks back. |
Well the general agreement was there, but ECMWF was never particularly enthusiastic (IMHO). The reality only avoided the NE'ly by a few hundred miles as the LP ended being further north (as ECMWF had been suggesting). I think it's a good example of how minor differences in set-up can have major differences locally. Of course, my take on it could be completely wrong - I've not yet got into the habit of regular, frequent checks. But it is worth remembering.
These two links may help:
Grauniad on UKMO
ECMWF model comparison (PPT).
There is also a model comparison somewhere on the site for GFS as well, but I never bookmarked it.
Last edited by Then you can post your own questions or snow reports... on Fri 27-10-06 10:05; edited 1 time in total
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skanky and brian, many thanks - more homework for me!
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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.
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rob@rar, I've only skim-read the PPT file. The main bit are the graphs comparing model accuracy over time. They do this for the 500mb plots and basically just see by how much they vary from the forecast.
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skanky, good to see that the forecasters are getting better with time!
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