I need help changing the x-axis labeling

Difficult to say much from a picture. Are you using an XY scatter chart or a line chart? You say that you want to use "stations" for the x-axis data, which I assume is column A and it looks like column A is text, so I would expect a line chart. What range are you using for the horizontal/category/x axis values? If you want to use stations/column A for the x axis data, I would expect you to use A3:A17 for the horizontal category x axis data.