The dead man had a dream - that means we should expect a change in weather. So before the grandmother said. Indeed, often such a not-so-pleasant vision happens before the rain. There is probably something in the unknown depths of the human brain that can act as a weather forecaster. But the logic is this: dead man - tears - rain. And what do the interpreters say about this?
Dream Book of Zhou-Gong
The dead man dreamed in a coffin - to profit. In general, all situations associated with ordinary funerals, according to this source, say alive about receiving material values. But if the deceased is crying, then you will be a participant, and maybe an organizer of a huge scandal. And what does it mean if you had a dream of a dead man rising from the grave? This nightmare portends terrible misfortunes in real life. A revived dead person will predict, on the contrary, very pleasant news. Perhaps what seemed like incredible nuisance would actually turn out to be a game of imagination. If you yourself died in a dream, you will be happy and healthy for many years. If a friend - such an enviable fate awaits him. To see an unimaginable dream in which a dead person eats food is a disease.
Dream interpretation of Tsvetkova
The dead man dreamed of a change of weather, rain. If you get up and walk around - wait for the guests. If the deceased is talking to you, then the soul of the deceased person has come to give you wise advice. When you do not quite understand what his speech is connected with, ask for clarification. They will come to you in your next dream or as an event in real life.
Miller's Dream Book
Just seeing is a warning. You can commit an unseemly act. Analyze the motivation of your daily behavior well. If the father died - follow the affairs. They are in danger. Possible attack from enemies. The deceased mother dreamed of illness. Perhaps you are too impressionable, which will lead to gossip behind your back. In general, you need to be more attentive to your health if you have a dream of a dead person. A relative in the coffin - you will need to fly to the aid of a loved one. If a deceased person is completely alive and looks great, it means that you are influenced by a bad person. You need to analyze your communication priorities, as the negative impact will push you to poverty. If you are talking with a dead person, it means that there is a black stripe ahead . Most likely, your health will suffer. However, things will go into decline due to the fact that you have to leave them unattended. Dead girls dream of a loss of honor. Her behavior will be condemned and ridiculed.

Russian dream book
The dead man dreamed of precipitation. Talking to him is an important change in life. You may need to decide whether to leave home. If he gives you something, and you took it - to the disease. If you called with you, but you agreed - to death. It also portends a misfortune in a dream in which a deceased person asks you for something. It is better to take this thing to the cemetery and leave it there in order to avoid trouble. The dream says that you have remained owed to the man, now deceased. Your conscience tells you that you need to remove this obligation from yourself in any way .