How old are your ducks? If they are fully feathered then they are absolutely 100% totally fine in the rain. They LOVE the rain and because they're waterproof, it won't chill them. HOWEVER, if yous are still babies with fluff (even partially), they CAN get chilled. When I have young, not-yet-fully-feathered birds outdoors, I provide them with shelter and also with a heat lamp so they can get dried out. They will seek shelter when they get cold--they're pretty self sufficient--but if it's chilly they may not be able to get dry quickly enough to prevent chilling.
Again, if they are fully feathered (even if they're not fully grown) then they do not need special treatment and will be just fine.
As for lightening, the chances of being struck by lightening are... well, so tiny that we use "struck by lightening" as a metaphor for a highly unlikely event. Ducks are short and squat, and electricity prefers a short travel to the ground and will generally seek the tallest conductive thing around to strike. So unless they are out in the center of a large pond or on a completely barren plain with nothing on it taller than them, then they're almost certainly just fine.
Again, if they are fully feathered (even if they're not fully grown) then they do not need special treatment and will be just fine.
As for lightening, the chances of being struck by lightening are... well, so tiny that we use "struck by lightening" as a metaphor for a highly unlikely event. Ducks are short and squat, and electricity prefers a short travel to the ground and will generally seek the tallest conductive thing around to strike. So unless they are out in the center of a large pond or on a completely barren plain with nothing on it taller than them, then they're almost certainly just fine.
