Harvest Moon: September's Full Moon Explained

The Harvest Moon is the full moon closest to the September equinox. In 2027, it falls on September 15, about a week before the equinox and several weeks closer to it than October’s full moon, the Hunter’s Moon.

What makes the Harvest Moon unusual isn’t its color or size, but the timing of moonrise. Around the beginning of fall, the Moon rises soon after sunset for several evenings in a row, providing extra light during the harvest.

When is the Harvest Moon?

The 2027 September full moon falls on September 15 at 7:04 p.m. EDT, or 4:04 p.m. PDT. The date is September 15 throughout North America, although the exact local time will vary. Check the fact sheet above for the time and moonrise details in your location.

Harvest Moon dates by year

Why is it called the Harvest Moon?

The name refers to the extra evening light the Moon provided during the autumn harvest. Near the September equinox, the nearly full Moon rises around sunset on several consecutive evenings. Before electric lighting, that gave farmers more time to work after the Sun went down.

Harvest Moon is an old European name rather than a name shared by all agricultural or Indigenous communities. According to NASA’s history of the name, its earliest known appearance in published English dates to 1706.

Other names for September’s Moon

September’s full moon is also sometimes called the Corn Moon, particularly in years when it isn’t the Harvest Moon. The Algonquins of Pikwakanagan First Nation call September Kabone Kizis or Mdaamini Kizis, connecting the season’s corn with the cycle of life through the multicolored seeds arranged around each cob.

Does the Harvest Moon always happen in September?

No. Unlike most traditional full moon names, Harvest Moon isn’t tied to a particular month. It belongs to whichever full moon falls closest to the September equinox, the beginning of astronomical fall in the Northern Hemisphere.

Most years, that makes September’s full moon the Harvest Moon. Every few years, however, an early October full moon is closer to the equinox and takes the name instead. In those years, September’s full moon is often called the Corn Moon.

Why does the Harvest Moon rise at nearly the same time?

The Moon normally rises an average of about 50 minutes later each day. Around the Northern Hemisphere’s autumn equinox, the Moon’s path crosses the eastern horizon at a shallow angle. Its nightly movement therefore changes the moonrise time less than it does during most of the year.

For several nights around the Harvest Moon, the delay can shrink to about 25 to 30 minutes across the northern United States, and even less at some higher latitudes. The exact interval depends on where you live.

For the best view, find a clear eastern horizon and check your local moonrise time above. A Harvest Moon can look orange or red while it’s low in the sky, but that color comes from viewing it through more of Earth’s atmosphere—it isn’t a special property of the Moon itself.

The 2027 Harvest Moon and Mid-Autumn Festival

September 15 is also the date of the Mid-Autumn Festival in 2027. Celebrated in China, Vietnam, and other Asian communities, the festival follows a lunisolar calendar and is closely associated with family gatherings, harvest traditions, and viewing the Moon.

The two names come from separate traditions and are determined in different ways. Harvest Moon is based on which full moon is closest to the equinox, while Mid-Autumn Festival falls on the fifteenth day of the eighth lunar month. In East Asia, the Moon will look full during the festival evening even though the exact full phase occurs the following morning in local time.