what day does fall start
In the United States and most of the Northern Hemisphere, fall generally starts in late September.
Short answer
- Astronomical fall (the “official” seasonal start) begins on the autumnal equinox , which usually falls on September 22 or 23 each year.
- Meteorological fall (used by many weather agencies) always begins on September 1 and runs through November 30.
Why there are two “start dates”
- Astronomical fall :
- Defined by Earth’s position around the Sun.
- Starts at the autumnal equinox , when day and night are roughly equal and then nights start getting longer.
* In the U.S., this is what’s often listed on calendars as the “first day of fall.”
- Meteorological fall :
- Defined by temperature patterns, not the Sun’s position.
- Runs September 1–November 30 , which makes climate statistics and recordkeeping cleaner for agencies like NOAA.
How people talk about it
Many people casually call September, October and November the “fall months,” no matter the exact equinox date. Others personally feel that fall “starts” right after Labor Day (early September) when the weather and vibes shift to cooler air, school, and fall holidays.
Quick reference table
| Definition | When fall starts (Northern Hemisphere) | Who uses it |
|---|---|---|
| Astronomical fall | Autumnal equinox, usually Sept 22 or 23 | [5][4]Calendars, many “official” season listings | [4]
| Meteorological fall | Always Sept 1 | [7][3]Weather/climate agencies and many everyday uses | [3][7]
In practice, if someone asks “what day does fall start,” the most textbook answer is:
It starts at the autumnal equinox, around September 22–23 in the Northern Hemisphere.
TL;DR:
- “Official” first day of fall: the autumnal equinox (≈ Sept 22–23).
- Weather/meteorological first day: September 1.
Information gathered from public forums or data available on the internet and portrayed here.