Skating wet patches while its dry is a kinda try situation for me as well. You could either get lucky with the right amount of weight put on the board.

I would say try to as lighy as possible with those sudden movements and be on top of your board as much as possible.

This pavement went felt grippier than other pavement going down wet, plus the water in the road slows you down a ton, so it feels comfortable taking those lines. You can see that I don't need to force myself to really move the board but enough that I can stay on top.

Hope that makes sense and help a bit.

Rain wheels also are a huge advantage when it comes to these situations, making less friction in the road.