According to the Hurricane J Songfacts, the "J" in the song title is a sweet waitress named Jesse, who has got herself mixed up with bad company. The narrator decides she is too good for him and is concerned she is "gonna crash into the harbor this summer."
Jessie, I'm not joking around
I see the crowd you're hanging with and those kids don't seem positive
Don't all the cigs make you tired?
You know I'd never ask you to change, I'll only ask you to try