Board Thread:The Heroes of Olympus/@comment-29729973-20161016134842/@comment-29068459-20170912232706

But Percy wouldn't be able to.

For remember, Percy drew upon the sea for his hurricane against Hyperion, and the frozen sea for his hurricane in SoN. In fact, I somewhat doubt Percy can even create a hurricane in a fresh water environment, because his will essentially melds with the sea. And in Sea of Monsters, it was shown that Percy is far less powerful in fresh water than salt water (when their lifeboat moved from the sea to a river, he didn't have his perfect bearings anymore, and he felt like he had just come down from "a sugar high").

The winds, clouds, and lightning are all a byproduct of Percy's hurricanes, but it starts with the sea. If just given clouds and a bit of moisture in the air, Percy can't do jack squat.