Rain

One quarter of an inch! We finally got a little rain! We bless every drop! We even bless the clouds because they help what moisture that we have not evaporate. I have not read (maybe I need to) about why some areas don't get much rain, while other areas get lots of rain. I know that water evaporates and is stored in the clouds and that rain comes from rain clouds. But if there is no water to evaporate then how could it rain. In other words - if one square mile is dry and has no moisture to evaporate - then how could that area get rain again? If all of the lakes, rivers and creeks are dry there is nothing to evaporate and nothing for the clouds to store to use later.
When I was a child we had rain. We didn't irrigate or put sprinklers on our gardens, yards, fields or crops because it rained. The population had not exploded and the water table stayed at a normal level. As I got older we had to water our garden about once a week. The farmers started irrigating their crops. A sprinkler became a common sight in most yards. What happened? Is is part of the global warming? Is it because the population exploded and more people used more water? Is it because companies started to bottle water to be used elsewhere? Why? Something has happened to the rain. Something has happened to Mother Nature. What is happening to our planet?