I can see two ways to read the barrier Storm: the pedantic way, and the intuitive way.
Reading it the pedantic way, it only affects the character who encountered it. I came to this conclusion based partly on the discussion about Jolly Roger, which only benefits the character who plays it, and partly on the fact that other displayed/task barriers exist that refer to "characters at this location" or similar. Storm, on the other hand, is displayed by a location but only affects "you". By the letter of the rules, this seems to be the right way to play it.
The intuitive way to interpret it is that it affects any character at its location, because it's a storm so how could it only affect one person? Perhaps I should call this the thematic way. But the only arguments I can see to support this interpretation are theme, and the fact that the card is displayed in a "shared" location as opposed to next to a character (an argument which failed to work for Jolly Roger).
So... how are people playing Storm?