We put the poles through eyelets and then run the ropes out from carabinas(sp??) from the D's in the tarp.
This way no matter if the tarp does manage to lift above the poles, the carabinas and rope are still in place to hold the tarp. When in real doubt about the weather we have also run a full length rope right through every D along each side and tied down at each end by a heavy duty peg or just tied off onto vehicles.
Peanut