Oh noooo! Not an honest to-the-point answer! How rude! Did you want to read something like: "Teehee! Like totally whenever it's pretty much finished and stuff, you know? Like... totally omg!"
Here's a video showing a ship going into warp... within the atmosphere -- and not particularly high up, either. http://www.youtube.com/watch?feature=player_detailpage&v=zP9PLYJxjaM&t=410 Regardless of overall warp speed engaged here, warp is warp. Notice the distinct lack of... any disturbance, even though birds of prey…
Let's also not forget that the Klingon Bird of Prey enters warp speed while in among clouds on earth... and nothing bad happens, at all. Seems like a really lame trolling attempt.