The simplest interpretation of rain is tears and emotional release.
If you have been bottling things up lately, it's possible that you need to let your true emotions out and have a good cry. Perhaps you need to let go of whatever it is that you are keeping inside- you might feel better if you are more honest about your emotional state.
If you were closing all of the windows to sheild yourself from the rain in your dream- it's possible you're are afraid to tell people how you're feeling and trying to keep it at bay or shut them out. Or maybe someone else wants to open up to you and you feel you can't cope with that level of emotion so you're keeping your distance.
Another interpretation is that you see a difficult time ahead that you're not quite ready for yet and envisage negativity in your future.
Perhaps you think some area of your life has been 'rained on' lately and you feel a disappointment that your happiness has been affected by a person or an event. On the other hand- you might have an important event coming up that you fear will be rained on literally or metaphorically.
Another thought is- if the rain pooled- you might feel that your problems are just too much for you right now- perhaps it's time to ask for help from your friends, family or even a professional.
Tagged in Dream Interpretation