Question: things to do in san juan on a rainy day?
Answer: El Yunque Rainforest. Provided the weather is not too horrible, then why not head on over to El Yunque; after all it's named a rainforest for a reason. ...  Jump in the Car. ...  Take a snorkel / scuba / kayak trip. ...  Take an Adventure Tour. ...  Sector Sixty6. ...  Visit a Museum. ...  Shopping. ...  Catch a Movie.