Unless you are actually in the clouds lightning is not that terribly bright, not a problem. I can also display my FLIR and HUD on my heads down screens if i don't want to look outside
The flir keeps you out of the tunderstorms in the first place. It can not replace the radar, it complements it nicely though. (Once you are in the clouds the flir is useless).
CB is the meteorological abbreviation for Cumulonimbus. Cumulus means big and billowy, nimbus means rain. Also referred to as cloud nine. (The ninth group of clouds).