"Verifiable" is probably too much to ask, but I don't think it impossible that a few short-term "prophecies" were indeed made before the fact and approximately "fulfilled" -- Jeremiah's or Ezekiel's predictions of Jerusalem's fall, for instance, which were not beyond the reach of political prognosis to a Jewish mind free from, or adverse to, Judean nationalistic enthusiasm; Ezekiel's ones have a particularly genuine ring, as they coexist with others (e.g. on Tyre) which were not fulfilled. It seems fair to say that the prophets could not always be wrong (even a dead clock is right twice a day after all).
The limit of the historical method is that we can never be sure about fulfilled prophecies: only the obviously failed ones can be shown to have been uttered before the (non-)event.