As families begin to plan pumpkin‑spice outings and Halloween festivities, the astronomical calendar marks a key moment: the fall equinox. In 2026 the equinox will take place on Tuesday, Sept. 22 at 8:05 p.m. ET, according to NASA. This event signals the official start of the autumn season for the Northern Hemisphere.
What the equinox means
During an equinox the Sun’s center crosses the plane of Earth’s equator, creating a day when night and day are “nearly equal” in length, as noted by Time and Date. While the spring and fall equinoxes both provide roughly equal daylight, they each bring more daylight overall than the winter solstice, which offers the shortest day of the year.
When the leaves will change
Leaf‑color changes will vary by region. Most of the United States can expect the first noticeable shifts from late September through mid‑October, according to USA TODAY. In parts of southern California and much of the South, peak color may not arrive until November, while areas such as southern Texas and most of Florida often see the change as late as December.
How the equinox fits into the seasonal calendar
The fall equinox is one of two annual equinoxes, the other occurring in March and marking the start of spring. The equinox sits between the summer solstice, the longest day of the year, and the winter solstice, the shortest. After the September equinox, the days continue to shorten until the winter solstice on Monday, Dec. 21 at 10:03 a.m. ET, as reported by the Old Farmer’s Almanac.
Fun online surprise
Google has added a seasonal touch for those who search “fall equinox” or “autumnal equinox.” The search results display animated leaves of various shapes and colors that gently drift down the screen, offering a visual reminder of the season’s arrival.
Key dates to remember
- Fall equinox 2026: Tuesday, Sept. 22, 8:05 p.m. ET
- Typical equinox window: Sept. 22‑24
- First day of winter: Monday, Dec. 21, 10:03 a.m. ET
Whether you are preparing a backyard harvest, planning a family outing, or simply looking forward to cooler evenings, the equinox provides a reliable astronomical marker to guide your seasonal activities.
Original reporting: Las Cruces Sun News (HLL/CB) — read the source article.
