Identified flying objects

What is it about my third-floor balcony that objects both animate and inanimate appear to have this irresistible urge to hurl themselves off it and into the void below?

One such apparent suicide featured our large, green parasol, which lifted itself clean out of the middle of the table and over the balustrade mid-meal as we and our lunch guests looked on, our mouths agape. It then floated down Mary Poppins-like to the garden below in a somewhat surreal slow motion, surviving its unexpected flight with just a broken rib.

Of course, I then had to go and ring on our ground floor neighbours’ door and ask for it back, trying to look nonchalant as I first walked through their flat and then took the lift upstairs holding a slightly muddy and bent seven-foot parasol.