I once had to do an emergency takeoff. On my way back to CO from Oshkosh in 2015, I had stopped over in Storm Lake IA for fuel. I called the briefer for the remaining leg home, world's chattiest guy slips in a "We've got a thunderstorm with tornadic activity that should be at storm lake in about 30 minutes" doesn't seem to think that's too significant and keeps talking, all the meanwhile I'm very VERY rapidly collecting pax from the bathroom to get them the hell back in the airplane to get out of there. I had everyone sitting in the plane ready to go and this guy was STILL jabbering on and on. I eventually had to interrupt him that we were leaving IMMEDIATELY to avoid the previously reported tornado. So... first emergency takeoff, that was cool.