The dream of heavy rain means that while you were sleeping storm has passed by. The noise of falling raindrops was external stimulus which induced your dream. So, dreaming it means that your sense of hearing is working even when you sleeping.
Additionally, fear of getting wet can be the reason of your dream. This is internal stimulus which can introduce you to very real dreams. If you don’t like water when it falls on you, when raining, then such psychological experience is is the meaning of heavy rain. It means that your fear is taking over you and following into dreams. An umbrella should always be prepared in order to be ready to help you.
If weather conditions outside at night was free of rainstorm and the precipitation doesn’t bother you, then your dream about heavy rain is a blessing. First, you are blessed because your mind is free of worrying about weather conditions. Second, this dream has symbolism of vitality, spiritedness and forcefulness. Also, it means growth in financial efforts and personal proficiency. So, dreaming about heavy rain symbolizes success in your professional life and family relationships.