First, here are some definitions, then my interpretation and recommendation for further investigation into your dream meanings...
-To dream that you are climbing a hill, signifies your struggles in achieving a goal. To dream that you are standing on top of a hill, signifies that you have succeeded in your endeavors or that you have now have the resources to complete a task at hand.
-To dream that you get wet from the rain, indicates cleansing from your troubles and problems. Rain also symbolizes fertility and renewal.
-To see and hear rain falling, symbolizes forgiveness and grace. Falling rain may be a metaphor for tears, crying and sadness.
-To see lightning in your dream, signifies sudden awareness, insight, spiritual revelation, truth and purification. Alternatively, lightning may imply a shocking turn of events. It suggests the many forces governing your life may be beyond your control and even destructive.
-To dream that you are struck by lightning, symbolizes irreversible changes occurring in your life. It is a transformation of sorts.
I think you already knew, if even subconsciously, what your dream was trying to tell you. Or, you've already felt some of the changes beginning to occur and your dream is trying to make sense of them- and communicate a message to your conscious mind.
Regardless though, your dream tells you of exactly what you think it does- depending on your position on the "hills" (climbing them or already on top), shows that you are either currently enduring struggle or have recently overcome some- and the rain along with lightening (and specifically being struck by it) signifies a "change." I think by your trying to run from it, you are afraid of this impending change, but your dream reminds you that it is coming whether you want it to or not.
If you have any form of divination that you practice, I suggest looking more into this "change" that is on it's way, so you can better understand it, and possibly work to correct it if that's not the direction you want to go.