<HTML>Welcome to the world of concert tunings! How about adding the hot lights of an orchestra set - up to the affects of the outdoor air?  It can be helpful to anticipate some of this trouble by tuning the first tuning a cent or two sharp. With the changing air, the piano will probably still be a bit sharp, or at least close, when you get to the tuning that counts. Easing the piano down into a tuning is much more stable the easing it up. It can also be helpful to cover the piano when the wind blows in, or the lights come on. Also, ask the tech's to leave the lights on somewhat while you do the second tuning, so the piano doesn't get jerked around as much. </HTML>