Considering how quickly drones are developing and becoming adaptable to changing conditions I expect that they will be able to fly in any weather that a human can in the not too distant future .
It will be the proving of their saftey that will be the issue plus getting humans willing to travel in them .
I suspect they will introduce autonomous drones slowly in limited use ( away from humans ) to prove the technology . Just as they are doing with autonomous cars it is only a time and development issue . It is going to happen .
Think about the early years of powered flight . Can you imagine how alien that would have been to the general population ? I don't know the numbers but I'm sure the crash rate ( and deaths ) would have been off the charts in those early years .
And yet , because people could see the potential benefit of powered flight , they persisted .
Look where powered flight is now .
Same with drones and other autonomous vehicles now . The benefits and the capabilities far outweigh the disadvantages .