Autumn (UK, and Commonwealth countries usage) or Fall (North America, specifically US and Canada usage) is one of the four temperate seasons. While the term Fall gradually became obsolete in Britain, it became the more common term in North America.

Please Note: For purposes of picture label associations on HikeArizona.com, we will use the Name: "Autumn - Color Foliage" rather than "Fall - Color Foliage" which occurs wherever deciduous trees are found.

Autumn marks the transition from summer into winter, in September (Northern Hemisphere) or March (Southern Hemisphere) when the arrival of night becomes noticeably earlier. Meteorologists (and most of the temperate countries in the southern hemisphere) use a definition based on months, with Autumn being September, October and November in the northern hemisphere, and March, April and May in the southern hemisphere.

According to United States tradition, Autumn typically runs from the day after Labor Day (i.e. the Tuesday following the first Monday of September) through Thanksgiving (i.e. the fourth Thursday in November), after which the holiday season that demarcates the unofficial beginning of winter begins.


Source
Wikipedia, the free encyclopedia