If each stand is rated for the full gvw then that is not going to be the issue. The only issue I can think of is the stands stability in two places. The part that is actually touching the vehicle ie will the vehicle slide /get pushed off without knocking the stand over or perhaps better said the connection between the stand and the vehicle and secondly the base of the stand or footprint. Is the footprint of the stand more than the tire it is displacing? Bottle jack perhaps not, actual jack stand probably ok. I would park nose or tail into the wind and only raise the vehicle the least amount as possible. I seriously doubt a 60mph wind is going to blow over a van but it may blow it off the stands if they are not appropriate.