When Does Fall Begin? A Look at 2026 Seasonal Transitions
The start of fall in 2026 depends on how you define the season. Meteorological fall began on September 1, marking the start of a three-month period based on the annual temperature cycle. Astronomical fall, however, begins with the autumnal equinox on September 22, 2026, at 8:05 p.m. EDT (00:05 UTC on September 23). This equinox marks the moment the Sun crosses the celestial equator, signaling the official start of autumn in the Northern Hemisphere. Beyond these definitions, phenological fall, which is based on natural signs like changing leaves, migrating birds, and cooler mornings, varies by location and environmental conditions. In some areas, fall may already feel present, while in others, summer-like conditions may persist well into October.
