I have a question for geology buffs or professionals.

We are gardeners and pay an inordinate amount of attention to weather. At least two periods in the past three years, we have watched storm fronts split right along the Mississippi River, resulting in rain for points east and west and none here. We live about eight blocks from the levee. When rain has deigned to fall, it has fallen more heavily at my in-laws's house, just five more blocks away from the river. It has fallen even more heavily three miles up the highway.

I contend that the Mississippi is a large, fast-moving body of water that has a direct effect on our weather because of temperature or evaporation or something else.

Am I being unsophisticated? Can someone knowledgeable give me a clue? What about a suggestion for a google search?