Squats, dead lifts, cleans, high pulls.
Once you can dead 1.5 times your body weight, start researching plyometrics and get into some light routines. Plyometric training won't make you fell tired or give you Delayed Onset Muscle Soreness (DOMS) that conventional training does...don't mistake this for meaning that nothings happening! Plyometric training can massively strain your ligaments, tendons, joints etc... The fact that you don't feel it doesn't mean its not happening. Its very easy to overtrain with plyometircs, trust me!
As you slowly accustom (very slowly) to plyometirc training you might consider complex training regime. Complex training is a hybrid of power lifting and plyometric training regimes. I used it years ago, like 8 or so, and my acceleration off the mark measurably improved.
However, I ended up on a multi year downward spiral of surgeries, rehab and injury. I certainly won't say that plyometrics or complex training was the fault, my ego was. I tried to progress to far too soon and ended up under the surgeon's knife too often. This is very easy to do when you're used to conventional weight training where you feel the pain/DOMS and its easy to tell that you're over doing it. Its much harder to figure this out with plyometric and complex training so be conservative, very conservative.
Also, I'm not sure how much benefit complex training ing would have for skiing. Rugby was my thing at College and complex training looked to offer big benefits in a sport where the ability to still generate moments of power even after running around like a mentalist for an hour or so would be huge. Seeing as a park or pipe run is better measured in seconds, rather than minutes or hours, may mean that complex training offers little benefit and increase the risk of injury to greatly to be worth it.
All of the above is based on what I did almost a decade ago, its probably out of date so don't think of my comments as a basis for a training program, think of them as a starting point for you to do some research into what is proven to work today. And I do mean proven, for every ounce of truth out there, supplement companies, fitness gurus, etc... publish tonnes of crap! Assuming everything you read is of dubious reliability, including (if not especially) me!
