One of the most challenging situations you get with thunderstorms is on departure. The reason for this is that quite often it is difficult to get a good idea of what is out there, because very often the departure calls for a big turn after departure, and the radar is not painting the departure route very well. You can try and get an idea as you taxi out. But not always.
You sit on the end of the runway and assess it all. Look out the window. Watch a departing aircraft, and compare tracks. Having made a plan, discussed it, spoken to ATC and kept them in the loop. Consider going back to stand and going home saying "it is all to difficult, and I miss my children". You finally blast off down the runway.
As you get airborne the situation can change very rapidly as new information becomes instantly available. As you change to a departure frequency, fly the SID, watching the radar, trying to work a very dynamic situation, then you transmit... blocked, again transmit... blocked. Now you are staring a CB in the face....
I have 360 tonnes of 744 strapped to my rear, absolutely no spare performance, still got the flaps out as you have still not got the thing clean because of the noise abate.
What do you do?
Well of course, you manage to get through, you state your intentions, and try your best to keep everyone informed. But, it is very dynamic. And at it's most dynamic on departure.