I had this dream about my grand-dad:
How can logic explain this dream? Nostalgia may have triggered this dream. It is common for survivors to wonder where the soul of the deceased has gone. This is another motivating factor to trigger the dream. This is confirmed by the dream theme, which is where the deceased has gone after his death.
You must be wondering how the woman got the color of his clothing right. She may have seen all his suits while he was alive, so she knew he owned a dark colored suit.
Many cultures talk about what the soul does, after leaving its dead body. One possible route is to travel all over earth, like a floating spirit. The woman may have remembered this myth and consequently, wen her brain created this dream, all the pieces fitted in.