Ranimin:
Its hard not to speculate that this was weather.A few posts have given some good insight and they need repeating:
a)Never ever try to outclimb a cell
b)Speed margin is critical-hence choice of level
c)Interpretation of wx radar is an art and surprisingly over-looked in training
d)Once in it,enage cws,disengage AT,set turb N1 and fly attitude only
All good points. "c" was handled occasionally by U.S. airlines by having ground school by the master, Dave Gwinn. Honeywell used Dave after his life at TWA. Unfortunately, Dave died too young.
Beyond that, I have to think of AF447 and the sidestick controls.