Cool "sweater weather" typically settles in by mid-to-late September . Peak Foliage: Colors generally peak throughout October . The South and Southeast
Used by climatologists and weather forecasters to track data in consistent chunks, this definition follows the calendar months. Meteorological fall runs from September 1 to November 30 . Regional Variations: When "Fall" Actually Feels Like Fall
For meteorologists, Autumn in America consists of three full months:
Because the calendar year varies slightly (due to leap years), the exact dates can shift by a day or two, but generally, astronomical autumn runs from late September through late December. when is autumn in america
There is no single "wrong" answer—only context-dependent definitions.
Most Americans recognize the change of seasons based on the Earth's position relative to the sun, specifically the equinoxes and solstices.
This is the most common official definition. It begins on the Autumnal Equinox , which usually falls on September 22 or 23 . In 2026, astronomical fall officially begins on September 22 and concludes with the winter solstice on December 21 . Cool "sweater weather" typically settles in by mid-to-late
In states like Georgia, Alabama, and Florida, autumn arrives much later and is often more subtle.
In high-altitude areas like the Rocky Mountains, autumn is beautiful but brief. Cool air can arrive as early as late August .
Often considered the quintessential American autumn, fall here is sharp and vibrant. Temperatures begin to dip in early September . Meteorological fall runs from September 1 to November 30
This definition is based on the autumnal equinox, the moment when the sun crosses the celestial equator, resulting in nearly equal day and night.
Northern states like Vermont and Maine see peak colors in early October , while southern parts of the region (like New York and Pennsylvania) peak in late October . The Midwest and Great Lakes