I plan to meet you at the station when you get off the train tomorrow.
Literal
Tomorrow train [from-から] get-off you [object-を] greet intend-is.
列車から降りる is a relative clause modifying あなた — 'the you who gets off the train.' 出迎える is a compound verb (出 + 迎える) meaning 'to go out and greet someone arriving.' ~つもりです states a firm personal intention.