I'll take a line of thunderstorms any day over most types of inclement weather. A line of thunderstorms is the most predictable type of weather you can ask for. It's going to be smooth upwind from them (usually), it is usually smooth even when you are close to the well developed ones and you will have improved viability (usually) unless they are embedded. Even though there may be a line of TH's they rarely join together to make a true line. And there is never a question if you should fly under them or not. A level 5 thunderstorm can way 450 thousand tons. When it decides to come down... well you dont want to be there in an airplane. Much like the defensive line of the Chiefs, if you are patient and look for the right clues they WILL let you through without having to go over the top.