。
I should be in Paris by this time tomorrow.
Literal
Tomorrow [possessive-の] this-about-time [topic-は] Paris [in-に] be [expectation-はず].
~はずだ expresses expectation based on reason — 'I expect that...' or 'it should be the case that...' Different from でしょう (pure probability); はず carries a stronger sense of logical grounding. 'I bought the ticket, so I should be there.'