Is a wife divorced by three when the husband says, "If you do not come to me tomorrow, then you are divorced by three," and she comes after sunset, knowing that he had divorced her twice before, and she was menstruating during one of those times?

If a husband makes his wife's divorce contingent upon a condition, then upon the fulfillment of that condition, the divorce takes effect according to the majority of scholars, whether the husband intended to enact the divorce, or merely to threaten, or to prevent. And a triple divorce counts as three. Sheikh al-Islam Ibn Taymiyyah is of the view that if he did not intend to enact the divorce, then he must offer expiation for breaking an oath, and a triple divorce counts as one. The reference for determining the breach of an oath is the intention of the one who swore it. If you intended your wife to arrive before sunset, then the divorce has occurred, and she is irrevocably divorced (baynunah kubra). However, if you intended "tomorrow" to mean the near future, then you have not breached your oath. And divorce pronounced during menstruation is valid despite its impermissibility (bid'iyyah) according to the majority of scholars. It is recommended to present this matter to trustworthy scholars.