 Poster: A snowHead
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skanky, the BSM thing, what am I looking at?
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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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Top Graph:
2m temperature (red), dewpoint (purple) and Relative humidity (blue).
I think that's 2m above ground, not sea level, but don't know how accurate the topographical part of the models are.
Second Graph:
Temperatures at various pressure heights. 1000hpa is roughly sea level, 850hpa is roughly 1500m, and 700hpa is roughly 3000m.
It also shows wind speed and direction (N is up). (From memory) 5 knots is a fetherless indicator and add 5 knots for each additional half feather and 10 knots for each full one (two halves).
Each inidicator is at the various pressure heights.
Note how the graph shows nothing below 810hpa - this suggests the data points here are above 2000m due to either the local weather station height or so that the model can cope with the mountains (which may hint at the imprecise nature of the model topographies).
Third Graph:
Sea Level Pressure.
Note, as it rises, the height equivalents of the hpa values in the above graph are likely to be higher.
Fourth Graph:
Precipitation. Convective are in the form of showers, storms etc. caused by instability in the air. Other rain is active (e.g. from the movements of air masses, fronts etc.).
Anything with a grey star should fall as snow.
Bottom Graph:
Cloud cover. Percentage cover by height (again in pressure equivalents).
On all graphs the horizontal axis is date and time.
These meteograms are available on Wetterzentrale (under "Diagramme") but for fewer places. They are also available from NOAA and NCEP for Lat/Long positions (D G Orf pointwed this out elsewhere).
Those two are from (I think) the GFS model, whereas this is for the Basel run NMM and Meso ETS models (though NCEP also runs the NMM model so I'm not sure what correlation there is).
Finally the GFS model isn't currently in full agreement with this model about this weekend, though there's a reasonable general agreement.
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skanky, do I need glasses, or is it just your familiarity with the system?!
Thanks a lot....
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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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It's some practice, some knowledge and you needing glasses 
Actually I was (sort of) wrong about something. There's two models and the meteogram is for NMM. The META meteograms are also available there, but there are fewer sites. The navigation bar at the top left is a good way to see all the products available. A good site.
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so, now in normal language?? Is it going to be positive or negative for the snow?
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Welcome to snowHeads, dio5, 
Spoeaking for myself, off to Val Thorens on Saturday, it is looking positive!
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I 'm going to Val Thorens to, leaving Friday 8th April.... till 17 april....
so let's hope the conditions stay good!!!!!
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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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Okay, now's the time to start asking.... SKANKY.... in 22 days we are off to Les Arcs for the EOSB (have you heard about it???) Please can you tell us that we're gonna be fine and have loads of snow... please
Last edited by You'll get to see more forums and be part of the best ski club on the net. on Fri 1-04-05 10:54; edited 1 time in total
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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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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<cough> 
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Michelle, sorry. I'll have a look at the models today and see what I think'll happen next week. That's as good as I can do, really.
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You know it makes sense.
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snow-forecast now has rising temps again by next wed in Courcheval with f/l up to 2400m 
I've been keeping an eye on what the ESF say about snow depths in Courcheval:
27/3 73cm 154cm 5cm fresh
28/3 73cm 153cm 2cm fresh
30/3 68cm 150cm 3cm fresh
31/3 72cm 157cm
1/4 74cm 160cm
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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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Poster: A snowHead
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| Quote: |
| Skanky I assume that at other times, things are more stable and therefore longer range forecasts can be more reliable but generally, I've always found it amusing that sites like snow-forecast.com give you three day forecasts for free (which are of some use) but make you pay for six days which right now are not worth the pages they are written on. |
Yeah, there are times when the forecast can be reasonably accurate out to over a week (ignoring the finer details). However the real reliability is to about three days (though again sometimes that can be a problem - esp. with snow events). I'd never bother paying for a siz day forecast - they'll get it right sometimes, but, IMHO, they'll give you little more accurate info. than a national weather service's general, five day forecast, and they are normally free. The new GFS will be available soon (maybe too late for this season), which has higher resolutions out further (currently 84hours is high resolution and it's lower past that, but the new one will be high res until 180 hours I think) and improved algorithms in some areas. This should improve reliability for longer terms for that model. The UKMO & ECMWF models are reasonably higb res out for a while (the UKMO covers a smaller area so can be), but their data is less generally available so are of less use to non-professionals.
I'm a complete novice, but I'll compare UKMO, ECMWF and GFS and look for variations between them and between runs. If may then check GEM, JMA, etc. for further agreements. The more agreements there are, the more I'll be confident about what's coming up. This can take a while - esp. if I've missed a couple of runs as I don't have run-run variability to compare. If you're looking short term - out to 132hours, then UKMO FAX are (generally) pretty good as they are done by forecasters using comparisons of the all the different models. Even so, you can easily see how much they can change for anything over 72-96 hours.
I hope to have something sometime this afternoon, but I'm a little rusty as I've been too busy to look much recently and most of the stuff I've read in the last few weeks seems to have been forgotten. 
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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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Can't remember the exact quote, but as Admiral Fitzroy (Darwin's Captain and the inventor of the published weather forecast said), the only certain thing about the weather is that it's unpredictable.
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You need to Login to know who's really who.
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ECMWF, GEM, & UKMO 00z
GFS 06z
JMA 12z 31st March
Monday From Midnight:
Multi-centered LP over Iceland with cold front extending down through the UK, with HP west of the Azores. Small LP over the Balearics. HP over northern Italy with a a trough(-like) feature over northern Europe, lareg HP to the east. (ECMWF, FAX, GFS, with some agreement from JMA & GEM & DWD). Across the Alps there's quite a strong 850hpa (1500m) temp gradient with most of the Alps in the negative temp. air - getting colder the further south you go. This cooler air will move away as the day goes on. Precipitation from the LP in the MEd may well affect southern areas, with the odd light flurry further north, but no more than a couple of centimetres here and there.
Tuesday From Midnight:
LP over Iceland moves northwards and eastwards dragging the associated cold front through central Europe - weakening as it goes. The LP in the MEd fills and moves south. HP starts to build over the centre of the continent. Som disagreement here with UKMO wanting a second, stronger front down through France, that does not appear on any of the other models - though GFS hints at a weaker, occluded front further NW. The FAX chart shows this second front trailing through Ireland. Another small LP appear SW of Ireland on ECMWF & GFS, this does not appear on GEM, UKMO or FAX. Stronger general disagreement from JMA so I'll ignore that one from now on. Warmer 850hpa air moves up into central France, but does not affect the Alps. Chances of some precipitation from convection (showers) so local differences in amounts.
Wednesday From Midnight:
ECMWF & GFS both run the SW LP up through the UK to Scotland, the UKMO refuses to acknowledge its existence, GEM hints at it but nothing more. All models build HP over northern Italy and the Alps, UKMO has a small LP again over Sardinia. FAX charts note this by showing a weak occluded front over central Italy. All models show signs of a front moving down from the UK into Europe, but at different positions and speeds. The warmer air over France will push eastwards across the Alpine region throughout the day, but will 'break-up'. Following it will be the occluded front which may reach the mountains that evening/night. It should bring some precipitation.
Rest of Week:
All models (ECMWF, GFS, UKMO & GEM) want to send some LPs through the UK. These system(s) are of varying depths and positions but there is a general trend to bring in colder air down from the north as the LPs move through - with them programmed to take a reasonably southerly track - with GFS wanting the more northerly of all the models (and thus one where there's least affect for the Alps). GFS does however want to run a decent sized weather front through the whole area Thurs/Fri with some more showery stuff in behind. It then build HP quite quickly over the Bay of Biscay. ECMWF & UKMO don't go out that far, but there's a definite suggestion of them wanting to do the same thing. I would say that it's reasonable to think that it'll get colder Thurs/Fri with a decent snowfall for all/most areas those two days. After that it's difficult to say, it all depends on the HP over Biscay and whether that can take hold. Monday's charts should be interesting.
Two points to note:
It's still looking okay for Scotland for next weekend - though it may not get cold enough for great conditions I'd certainly expect there to be some snow on the hills.
The 12z GFS will be out now but I haven't had time to look at that.
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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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You'll need to Register first of course.
You'll need to Register first of course.
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skanky, quality - that's all I can say whilst taking respectful notice of your sig line as well.
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thanx, please keep us up to date!
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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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metcheck's long term forecasts predict a freezing level (for val thorens) at about 600m!!! for saturday 9th of april ....! that seems cold to me ...
let's hope it will come true
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metcheck's long term forecasts predict a freezing level (for val thorens) at about 600m!!! for saturday 9th of april ....! that seems cold to me ...
let's hope it will come true
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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dio5, think its all about what happens thurs/fri....after that, as you say, looking good!
(still a long way off tho in forecasting terms!)
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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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| tomski01 wrote: |
especially given what skanky forecasts in his latest run-down from yesterday! :sH:
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The French weather service say rain below 2400 meters for Thursday.
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as long as it's only one day of rain and it becomes very cold after that... it's still fine by me! but not a whole week of rain!
(want to go skiing, not waterskiing) 
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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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tomski, I will post his experiences as soon as i ve seen him (tomorrow i guess...)
so let's hope we ll be allright... I m leaving for Val Thorens this Friday, and will be praying for snow for the rest of this week...
grtz
d
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Poster: A snowHead
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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tomski01,
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| PPS Im not skanky so i may be talking rubbish, |
I am skanky and may be talking rubbish. Not looked at anything yet, will do so.
Remember air flows clockwise round a HP and anti-clockwise round a LP. So to get northerlies you want to be west of a LP and East of a HP system.
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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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according to meteo.fr it will be snow for Friday above 1800 meters (in valtho)
Thursday afternoon rain, with a snow line at 2300 m
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You need to Login to know who's really who.
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dio5, yeah the cold front moves through Thurs/Fri night. Some disagreement from the models about the end of the weekend - they all ridge the HP over Europe and it's the exact line of the ridging that determines whether the Alps stays in the cold air or warmer air moves in again. Currently erring on the side of cooler (though never cold), than warmer but it's too close to know for sure.
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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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You'll need to Register first of course.
You'll need to Register first of course.
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tomski01, hint for skiing above Champagny, when you get to bit where Kamikaze & Hari Kiri meet up, there's a blue run goes off to the side and rejoins at the lifts. When we were there this blue run was the run to take as the red was very crowded and stoney and as it was moguly, people were picking their way through it all. You couldn't get any momentum up and had to walk the bit to the lifts. Taking the blue was better as it was quieter and you could let it run longer and so got further up the slope. Obviously if conditions are better then that might ne be such an issue, but I suspect they'll be similar to when we went.
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tomski01
haven't really heard my friend from la plagne in person yet, but the first stories go that the snow was quite ok and he has had 2 days of snowing and quite good powder.... the bad part is that the first night they were robbed in their appartment while sleeping  .... they forgot to lock the door....lots of stuff stolen (skipasses, snow pants, glasses....)
I ll tell you more as soon as I ve spoken him....
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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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tomski01, they're fun, trust me on that one.
dio5, it's worrying that someone tried the door and found it unlocked.
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FAQ
) to understand why the forecasts seem to be swinging around all over the place, I have been paying particular attention to the GFS 850hPa pics (not because I think they are any better than other models but simply as an exercise to see how much variation there is between forecasts at the moment) and it seems to me that for anything past about three days, every six hour update can bring a very significant change in the map so I can certainly see the difficulty of forecasting anything past that period. This has been the case for pretty much the last two weeks that I have been watching closely.
