The listener has no control over the first four items in the above list, but it is valuable to have an understanding of these factors. Frequency is a way of noting or measuring the different parts of the broadcast spectrum. The AM band is a low frequency service dominated by ground wave propagation during the day and sky wave propagation at night. This is why FM reception does not change from day to night. Distance from the broadcast antenna is one of the major factors in FM reception.
Signal strength decreases as the distance from the antenna increases.
For example, all other things being equal, the signal strength in Chapel Hill is four times as strong as the signal in Durham. Atmospheric conditions do not have a dominant influence on FM reception. The most commonly occurring atmospheric influence is the inability to receive distant stations during unusual conditions. These conditions occur more often in spring and fall. Terrain is a given.