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I think she might be waiting at the station around now.
Literal
She [topic-は] around-this-time station [at-で] is-waiting [might-not-be-that-のではないか] [quotative-と] think.
~のではないかと思う is a beautifully hedged frame for tentative thought: literally 'isn't it the case that... I think.' The の ('the situation that') nominalizes the embedded clause, ではないか asks rhetorically 'isn't it,' and と思う wraps the whole thing in 'I think.' The result is much softer than と思う on its own — it's the speaker floating a possibility while leaving room for others to disagree. で marks the station as the location of waiting (with で for activity), distinct from goal に.