всё что я смог найти на форумах это вот такая цитата, хотя по понятным причинам ручаться за её достоверность не могу
sb from spain:
Well, there were severe thunderstorms in the area, but they could be avoided. I was on TP178 that night, leaving from GIG to LIS one hour earlier than AF447, and flying along the same route, and we only encountered light turbulence. Ditto for a colleague of mine who was on IB6029 to MAD, leaving 15 minutes later than AF447. He claims he didn't notice any turbulence... So both flights must have found a way around the worst thunderstorms. Why didn't AF447 manage to do the same?