i tried doing that exact same thing during the winter. it didn't really work out great, but i have a flat yard and a 6' high drop in. thre reason it didn't work was i more because i set it up bad, it probably would have worked if i set it up better. my advice to you would be to really plan everything out and make it as legit as possible, like really plan it out and use good shit when building it. if your yard is sloped you should be all set on speed,(you might have mentioned that in the title can't remeber) otherwise, just make the transition from one rail to the next real smooth, would recommend making the first rail a down rail and the second pretty low to the ground and remember to follow the 11 tips for keeping speed.
sparknotes: if your drop in is 10' high you should be good. just make it legit and work for maximum speed.