J2Ski Forum Posts and Replies by SwingBeep

Admin wrote:Our forecasts are driven, as we've discussed before, by GFS and the way to view them is as the "latest best guess".

Trouble is the GFS is pretty poor at guessing the weather in the mountains. The GFS is a hydrostatic model, hydrostatic models use pressure as vertical coordinates in the forecast (e.g. make forecasts at specific isobars) and essentially make general approximations about topography. The main reason that J2ski and other similar websites use the GFS is because the data are free. This guide explains how it works and what the limitations are http://www.soaringmeteo.ch/modelEN.pdf

The ECMWF (European Centre for Medium-Range Weather Forecasts) model uses altitude and more accurately accounts for topographic effects on weather systems and is therefore generally more accurate, unfortunately the data are not free.

J2ski also seems to have problems with the post processing of the raw data. In today's forecast for Zermatt J2ski is forecasting thundersnow on Saturday, https://en.wikipedia.org/wiki/Thundersnow this is an extremely rare weather phenomenon that I have never ever seen during the 27 years that I have lived in the region. It is also forecasting 2 cm of snow at village level even though the temperature is forecast to be 8⁰C! Local forecast for night time temperature is 3⁰C.

The Precision Ski shop in Courcheval 1650 is one of 46 similarly named shops belonging to a company called Danisports https://danisports.fr/ they also rent skis via affiliated shops under the Ski Republic brand. In total they have 25,000 pairs of skis for rent, they are all serviced down in Séez on a fully automatic machine at the rate of 90 pairs an hour.

The Intersport shop is an independently owned business that is a member of the Intersport buying organisation. They service their skis in-house and operate their rental department in accordance with the AFNOR (French equivalent of the BSI) standard on the rental of winter sports equipment NF X50-007

It costs money to comply with the standards and employ trained staff, hence the difference in price.

Download the piste map http://www.matterhornparadise.ch/pdf/panoramakarten/panoramakarte_winter.pdf

Day 1, train up to Gornergrat (first train is at 08:00) and ski the blue runs down to Riffelberg, towards lunch time take piste 29 to Gant and take the new chairlift up to Blauherd then ski down to Findeln for lunch at the Findlerhof (you will have to book). After lunch take the lifts back up to Blauherd and the cable car up to Rothorn, ski down to Kumme and then take piste 11 back to Blauherd and ski around there for the rest of the afternoon at the end of the day take the Sunnegga funicular back to Zermatt. If you must ski down take runs 2 and 2a.

Day 2, Cervinia Matterhorn express (opens at 08:30) to Trockener Steg and then the cable car up to the Kleine Matterhorn, take the lift up to viewing platform. Then ski down to Testa Grigia and on to Cime Bianche (7 & 35) and down to Salette. After that go back up to Cime Bianche and down 7 to Cervinia, from there take the gondola up to Plan Maison and then the chairlift. Lunch at Chalet Etoile on piste 4 ski around in that sector in the afternoon and take the chairlifts up to the Theodulpass to get back to the Zermatt (keep an eye on the time, last lift from Plan Maison is at 15:45). Take the gondola back down to Zermatt from Trockener Steg of if your still feeling fit from Furgg. If that sounds a bit too much leave out the runs to Salette and carry on down 7 to Cervinia.

If the weather forecast is better for day one than for day two go to Cervinia on day 1.

I think miss-alignment plays a considerable role, after sorting out my fore-aft alignment largely by reducing the binding delta and my lateral alignment having my boots canted I felt a lot better balanced than before. If the angles built into the boots and bindings are pushing you out of balance you are more likely to fall in an awkward way.

I also think technique also plays a role, I don't think skiing with your feet wide apart and upweighting to initiate turns is a good idea. This bloke had a very near do.





The bindings didn't show any signs of releasing as he fell backwards, and only released some time after he hit the deck.

It could well do, inadvertent pre-release is really undesirable and can lead to very serious injuries if it happens when travelling at speed. Imagine what's likely to happen if your outside ski suddenly drops off at the apex of a turn whilst your travelling at 60 km/h. There must be a reason for the pretty tight sole thickness tolerance.

There may be still some doubts about whether global warming is taking place, but alpine warming is in full swing. The temperature rise in Austria since ca. 1880 amounts to nearly 2°C, compared to average global warming of 0.85°C



People visiting the alps in winter probably won't notice much difference as the temperature increase has mainly taken place in spring summer and autumn, and the effects on precipitation have been masked by snowmaking and snow management.

Last week I watched a program on the German TV channel 3sat "Der Schnee von Morgen" (The Snow of Tomorrow) in it Michael Manhart the managing director of the Bergbahn Lech - Oberlech who is known in the industry as the 'Snow Pope' said that the quantity of natural snow these days was insignificant, his exact words were "Mickey Mouse"

Locally over the last 25 years I have seen several climate related changes, the Scots pines are dying out at lower altitudes and being replaced by downy oaks which normally grow in submediterranean regions. Most of our drinking water is provided by springs that are fed by snow melt, these are providing less water than they used to.

This week there was a report in the local paper that said that because of the small amount of natural snow we have received this season (30-60% of the average amount) Sass Fee and Zermatt may not be able to open their summer ski areas.

The sole thickness for alpine ski boot is covered by ISO 5355: Alpine ski-boots -- Requirements and test methods. The thickness at the front is supposed to be 19 mm ± 1mm and 30 mm ± 1 mm at the heel.
It might be relevant for renters, as the hire shops are supposed to check the boots and bindings in accordance with yet another standard ISO 13993: Rental ski shop practice -- Sampling and inspection of complete and incomplete alpine ski-binding-boot systems in rental applications, but they seldom do.

I think it stands to reason that a loose fitting boot or a boot that's slopping about in the binding due to worn soles won't release in the same way that a well fitting new boot will.

A considerable amount of research has already been carried out, have a look at the publications published by the International Society for Skiing Safety http://www.isssweb.com/ and the International Society for Snowsports Medicine http://www.sitemsh.org/

All the alpine countries collect information on the numbers and types of skiing injuries, this is how they break down in Germany.



The situation is much the same in other countries. As you can see the there is a very high incidence of knee injuries, especially for women.

The injuries are often caused by falling backwards. Current ski bindings are mostly designed to release during a simple forward fall (upward release of the heel piece) or during a forward fall with body rotation (sideways release of the toe piece).

The most dangerous situations occur when a skier is leaning too far back. This most commonly happens after a skier has fallen backwards or when they are trying to get up while still moving after having fallen to the rear. The skier's hips fall below the knees and the uphill ski becomes unweighted. All of the weight is transferred onto the tail of the downhill ski. Often the ACL gives way at this point.



In 2013 the Swiss Council for Accident Prevention commissioned a literature study "Ski equipment-related measures to reduce knee injuries" from Prof. Dr.-Ing. Veit Senner of the Technical University in Munich http://www.professoren.tum.de/en/senner-veit/ an acknowledged expert in the field. The full study (140 pages) is in only available in German, but there is a short version in English https://goo.gl/UQUaKy that includes an explanation of the injury mechanisms and details of technical possibilities for the reduction of knee injuries.

I think it's mainly to do with how you fall rather than anything else. Other factors could also include poor skills due to many skiers only taking a nominal number of lessons these days, ski boots that are too big, boot binding setups that force the skier into the back seat, and the excessive consumption of alcohol.