I’m not 100% sure because obviously it happens to me in faraway countries. But yesterday I flew in southern Florida and there was a thunderstorm in FS 2020 despite there being relatively few clouds at the time at Key West.
Them, today I flew around Shizuoka prefecture in Japan, and again there were thunderstorms. Very cloudy but no rain, but it could be.
And today I wanted to fly from Miami (until the pushback guy bugged and didn’t move, and when I tried to get myself into position I crashed into a building) and despite there being relatively few clouds, again a thunderstorm.
I don’t know about other people’s experiences, but it looks to me that as if in wanting to add thunderstorms in the new patch, they made them far too common