I've flown through some light mists over creeks without a problem but it is not a great idea for so many reasons. Think about even a momentary short circuit at 300.
FYI. The law states that you need to have your drone insight at all times. If it’s in the clouds , you can’t see it. that’s a issue.
So please be safe . Remember these drones are very expensive and can also hurt someone very quickly.
Thank ahead. Fly smart.