We would definitely advise against this. It's best to prep the surface you're applying your waterproof stickers to ahead of time. Ensuring you're working with a clean, flat surface will help the stickers adhesion, and will ultimately make them last significantly longer. If the surface you're applying your stickers to is wet, the adhesive may not dry down as well as it could, and this could cause them to fall off. However, once your custom waterproof stickers are applied, they are A-OK to get soaked! They will even hold up on the underside of boats, kayaks, and canoes! Let your creativity take the wheel with our weatherproof stickers.