There may be several reasons for this.
We may in fact have a precognitive dream which creates the feeling of deja vu when the event occurs and jogs our memory of the dream.
Precognitive dreams are well established as a real phenomena.
Past life experiences may trigger a dream like recollection of places or events we are re living etc.
The dream state is seen as a doorway to higher consciousness by many indigenous groups. So unless we have a deep prejudice about indigenous people we need to take notice of other philosophies.