How many days until First Day of Astronomical Fall?
First Day of Astronomical Fall is on Tuesday, September 22, 2026. There are 106 days left until First Day of Astronomical Fall. It is observed september equinox in the northern hemisphere.
Date & Planning Details
First Day of Astronomical Fall is observed september equinox in the northern hemisphere.
These dates use UTC-based September equinox dates. Local calendar dates can differ by time zone when the equinox occurs near midnight.
Usually treated as an observance, not a day off.
First Day of Astronomical Fall Calendar (2026-2035)
| Year | Date | Day | Days Left | Weekend? |
|---|---|---|---|---|
| 2026 | September 22 | Tue | 106 days | No |
| 2027 | September 23 | Thu | 472 days | No |
| 2028 | September 22 | Fri | 837 days | No |
| 2029 | September 22 | Sat | 1202 days | Yes |
| 2030 | September 22 | Sun | 1567 days | Yes |
| 2031 | September 23 | Tue | 1933 days | No |
| 2032 | September 22 | Wed | 2298 days | No |
| 2033 | September 22 | Thu | 2663 days | No |
| 2034 | September 22 | Fri | 3028 days | No |
| 2035 | September 23 | Sun | 3394 days | Yes |
What is First Day of Astronomical Fall?
The first day of astronomical fall is based on the September equinox, when the Sun crosses the celestial equator and autumn begins in the Northern Hemisphere. It is not the same as meteorological fall, which starts every year on September 1.
Calendar note
Astronomical fall follows the equinox, so its date can fall on September 22 or September 23 depending on the year and time zone.
Date variation note
In the Southern Hemisphere, the same equinox marks the start of astronomical spring, not fall.
Planning note
Use this countdown for equinox-based seasonal planning. For weather records, climate averages, or monthly planning, meteorological fall may be the more practical reference.
Weather note
Fall weather does not always begin on the equinox. Local temperatures, rainfall, foliage timing, and daylight changes vary by region.
Frequently Asked Questions
When is the first day of fall?
In the Northern Hemisphere, astronomical fall begins on the September equinox, usually on September 22 or September 23.
Why does the first day of fall change?
The equinox depends on Earth’s orbit and the calendar year, so the UTC date is not fixed to one calendar day every year.
Is autumn the same as fall?
Yes. Autumn and fall usually mean the same season. “Fall” is more common in American English, while “autumn” is widely used in British English and formal writing.
What is the difference between astronomical fall and meteorological fall?
Astronomical fall starts at the September equinox. Meteorological fall starts on September 1 and is based on full calendar months.
Is the first day of fall a public holiday?
No. It is a seasonal calendar date, not a public holiday in most places.
This countdown uses the selected timezone to keep the live timer and date table consistent.