There is a description in "Kiyushoran" (an encyclopedic book on cultures) that after the weather became fine, teru teru bozu is thrown into a river with a bottle of sacred sake after face parts were applied.
『嬉遊笑覧』という本には、晴天になった後は、瞳を書き入れて神酒を供え、川に流すと記されている。