 Poster: A snowHead
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thanks matt.
that's kind of what i thought from looking at stuff, but wondered if any of the experts - you know the "qualified" ones - could say for sure. 
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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More gems from Brian.....
So the currently available state of NWP (numerical weather prediction, 1st acronym in already ).
The clear leader in the verification stats and therefore the current leader of the pack is (drum roll .....):
- ECMWF, European Centre for Medium-range Weather Forecasts, it's a collaborative venture between numerous european countries.
They run twice a day (midnight and noon) and the freely available output goes out to 240 hours in 24 hour steps and consists of surface level pressure and 850 hPa temperature and wind charts. They run an ensemble of 50 members but we can't see it (except for one location in Holland, not much use).
Fighting it out for 2nd place, the other 2 members of the so called "big 3":
- GFS, Global Forecast System, the model of NOAA, National Oceanic and Atmospheric Administration, a US govt agency.
They run 4 times a day (every 6 hours) and the entire dataset is published for free by a variety of sites out to 384 hours in 6 hour steps (the first 180 hours at 3 hour steps). You get everything with this one, pressure, precip, temp/wind at various heights etc. etc. They run an ensemble of 20 members.
- UKMO, our own UK Met Office.
They run twice a day (midnight and noon) and publish pressure charts out to 144 hours in 12 hour steps to T+96 then 24 hour steps. They also publish temp and precip charts out to 72 hours. No free ensemble data, don't know what they do.
So that's the 3 it's worth looking at. Then we have the "lesser models". Actually that tag is a little unfair on ...
- GEM, the Canadian model, which isn't far off GFS and UKMO these days.
... but these aren't much cop:
- JMA, Japan
- NOGAPS, the US Navy
- DWD, the Germans
On top of that little lot, we have the FAX charts. These are produced by actual human forecasters using the model output and they draw on the fronts, troughs etc. This requires a pretty high degree of skill. It can be quite illuminating to look at the met office's ones though, as they have full access to their own model (obviously) but also the ECM and GFS, so you can sometimes get an idea of which model the real experts have confidence in.
So where can I look at all this stuff, brian, I (don't) hear you cry ?
Why at http://www.wetterzentrale.de/topkarten
and http://meteociel.fr/modeles/
of course !
Happy weather watching
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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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Afternoon all. This chart looks really useful - lots of info on one page. However, I am not 100% sure what everything means. Can someone help?
http://85.214.49.20/wz/pics/MS_070460_g05.png
OK, I think that the first chart shows cloud cover in 3 sections, high cloud, mid layer cloud and low cloud. If the white bit is fat, it means it is pretty cloudy. If the white bit is thin, it means it is less cloudy. Does the size of the white bit equate to % (ie a full bar = 100% cloud cover)?
The 2nd chart I take to be pressure at sea level.
The third chart is wind I think, and the higher the green line the stronger the wind is. Anyone know what this is measured in? Also, do the black lines give direction, and if so how do you read that?
The third line is temp. Is this given at the 850 hpa level?
Don't really know what the forth chart is...
The final chart is precipitation. What do the red lines mean?
Thanks in advance...
Ed
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You need to Login to know who's really who.
You need to Login to know who's really who.
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...and on the subject of precipitation, on the Wetterzentrale graph, if I am correct thinking that the precipitation forecast is for mm rain, then do you multiply that number by 10 to get forecast snow depth? Or summat else? I've got 3 weeks before I hit Les Gets but it's never too early to start planning... 
Andy
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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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andyph, as far as I know, it is mm for rain and cm for snow....
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brian
brian
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Snowmonkey,
- correct on cloud and surface pressure (bodendruck).
- windspeed is in knots (1 knot = 1.15 mph), direction is shown by the black lines as if they were the needle on a compass.
- Temp is given for 2m above the surface at whatever altitude the surface happens to be at (the one you've linked is 1862m, given at the top right). Red and blue lines are temp max/min, black is the dew point.
- next graph is relative humidity
- bottom is precip in 3 hour periods, red lines mean convective precip
andyph, yes, as a (very) rough rule of thumb, 1mm of rain = 1cm of level snow ... and welcome to  s
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brian, welcome back!!!
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Sorry Brian, a couple more questions
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- windspeed is in knots (1 knot = 1.15 mph), direction is shown by the black lines as if they were the needle on a compass.
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What about the fact that the main lines have little lines coming off them? And which end of the line is the direction?
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Red and blue lines are temp max/min, black is the dew point.
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Where does the dew point have to be in relation to temp in order for precipitation to occur? Or can it vary?
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red lines mean convective precip
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What does that mean?
I'm getting there, thanks in advance for your help!
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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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brian
brian
Guest
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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brian, I knew you would be the man in the know - thanks!
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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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If anyone could accurately forecast 10 days ahead, they would be very wealthy indeed.
Have a look at the synoptics for a few days on the trot for just 5 days forward and see how many of them are accurate. You will find its very few, unless we are talking about massive high pressure systems and stable jet streams. At the moment its hard enough to get accurate 3 days ahead.
I wouldn't throw away your fleeces just yet.
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What about the fact that the main lines have little lines coming off them? And which end of the line is the direction?
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Just seen the query above, now rather old. The number of little lines coming off indicates speed - the more lines, the windier. The end without any lines points to where the wind is GOING.
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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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Poster: A snowHead
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nickbuckers, welcome to S-Heads
Hi - you can find the lat / long of Val d'Isere, which is around 45.5N; 7E (type 45.5,7 into google maps & it'll show you that lat & long - longitude:East is positive & West is negative)
If you then put the longitude as 070 and latitude as 455 into this URL http://www.wzkarten.de/pics/MS_070455_g05.png you'll get the required meteogram
This shows the high;mid;low level cloud (blue is sky, grey is cloud): pressure: wind speed & direction: temperature: humidity (I think) & precipitation.
Change the values for different locations....
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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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Geoffers, Rogg - many thanks & happy new year!
I'll be using this a lot in the next couple of weeks - hoping for a bit of a refresh to the pistes....
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You need to Login to know who's really who.
You need to Login to know who's really who.
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Trouble is, trying to follow the arguments from the beginning, the fact that all the charts constantly update does make it rather tricky.... 
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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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Not sure if this is the right thread, but just wanted to give a quick heads up on some new forecast options on TWO. On the homepage you can now select 'Winter Sports' from the drop down menu. Once it has updated you can begin typing the name of the resort and the autosuggest will show you available options. Once your option is selected you can then either pick the 16 day or day forecast options for your forecast.
http://www.theweatheroutlook.com/default.aspx
If you want to use the old method for picking a resort and plotting graphs (as well as seeing the 16 day weather forecast, go to this page and select from the drop downs in the page body rather than header.
http://www.theweatheroutlook.com/twoforecasts/ski%20and%20snowboard%20weather.aspx
Time permitting I intend to add in more features to the winter sports forecasts before the start of the new season. Let me know if you've got any questions or requests.
Thanks
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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bwg, Looks great - easy to understand for GFS phobes like myself.
is there an altitude option to see the precipitation snowline on the way?
Ta
Martin
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"Looks great - easy to understand for GFS phobes like myself.
is there an altitude option to see the precipitation snowline on the way?"
There isn't at the moment. There are a number of different ways of calculating the snowline, but I'm not convinced any of them are entirely reliable. Does anyone here have nay thoughts on the best way to approach it? Data such as freezing level, 850hpa, thickness and lapse rates are availableto be used in the calculation. Rain turns to sleet and then to snow, and at first will be slushy and not accumulate etc. Is the snowline at the point where the transition begins or where the snow starts to accumulate?
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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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If you want to find the GFS graph near your destination ski resort I have tried to capture them here:
http://www.ski-finder.co.uk/mapgfs.html
Note: This does not display all ski resorts in Europe but should help you find the nearest GFS graph - comments/suggestions appreciated
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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ski-finder, excellent!
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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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Hello, to help me find the weather wiggles more easily I set up this map on Google over the weekend - just click on the snowflakes to see the plot for that latitute / longitude - initial version is small but click on it and the full version will appear in a new window.
Over the next few days I'll add a few points further east as well as more names of nearby resorts
Happy skiing!
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You know it makes sense.
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Nice work thebongolian!
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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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thebongolian, did you not see mine 3 posts up? 
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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ski-finder, thanks for the link, the graphs are very interesting, but it is a mystery (to me at least) why even 24 hours away the green GFS Hauptlauf can be so different (relatively anyway) to the apparent convergence of all the other so called "wiggles". The GFS graph for St Anton, etc (47/10) shows it now (03FEB 12Z) even better than the graph above. Anyone know what accounts for the difference and what we should have the greater confidence in?
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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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what about it? snow from gfs!!!
http://theweatherland.com/
Last edited by Well, the person's real but it's just a made up name, see? on Thu 10-06-10 22:26; edited 1 time in total
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You need to Login to know who's really who.
You need to Login to know who's really who.
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Next is looking very snowy and cold for the west - should be a great week for anyone heading out....
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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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Hi, does anyone know where i can find a GFS chart for Chamonix?
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You'll need to Register first of course.
You'll need to Register first of course.
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Find the lat & long of the location your after (Cham), then type in the (nearest whole number) values into an existing "wigglies" link - may not be the exact location, but near enough.
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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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FAQ
Was looking for it 
) - can someone assist?
