As one might guess from the term, diurnal temperature range means the variation between the lowest and highest temperatures during a given day at a certain location. This can vary widely, depending on the season and place. For example, the climate on the Front Range of the Rocky Mountains in North America has been known to change by as much as 100 degrees within a 24-hour period, while in the tropics temperatures tend to remain more stable, changing by, perhaps, 10 degrees or so within a specific day.