I have read this thread with interest and hesitated to post but now that the subject of "dry thunderstorms" has been raised, I'll make a small contribution.
Most of my career was spent flying in the northern hemisphere, a lot of it fairly far "north" at that. Towards the end of my 20K hours my employer began routes across the ITCZ and after some long chats with a friend with extensive experience there, I was very concerned about running into a CB which did not paint on the radar in the dark. He talked of using NVGs and various radar techniques to avoid such an event.
A couple of points, first I always made certain that I was in the cockpit during the ITCZ phase of flight - the bunk was not an option. Second I learned from other pilots that there were some creative ways to use the radar to detect CBs that would otherwise go undetected due to the lack of moisture. I won't go into them here, mainly because memory has caused details to fade, the point is that the use of radar is not an exact science - experience and technique is crucial. And that may well have been a factor in this accident.
I think I was as close to the edge of my seat transiting the ITCZ as I ever was during a CAT III approach to an icy runway.
Edited for format.