Wisconsin To See 'Friday The 13th' Harvest Moon In 2019

MILWAUKEE, WI — September’s full Moon is coming up, the so-called “Harvest Moon,” which is the full Moon nearest to September's autumnal equinox .

The first full moon after the autumn equinox is always referred to as the Harvest Moon, regardless of whether it falls in September or October. The September full moon is also known as the Full Corn Moon, so named by early Native Americans because it marked the time when corn was ready for harvest.

The full moon will rise at 7:19 p.m. on Friday, Sept. 13. It reaches its highest point in the sky at 12:14 a.m., according to observers. The moonrise will be located at 102 degrees east-southeast, which puts it rising over Lake Michigan.

The moment the Moon turns full will occur just before midnight—at 11:33 a.m. on Friday the 13th.

Why The Harvest Moon is Unique

According to the Farmer's Almanac, what sets this upcoming full Moon apart from the others is that farmers, at the peak of the current harvest season, can work late into the night by this Moon’s light. The Moon rises about the time the Sun sets, but more importantly, at this time of year, instead of rising its normal average 50 minutes later each day, the Moon seems to rise at nearly the same time each night leading up to when it’s full.

For example, between September 12 and 14, the rising of the Moon comes, on average, less than 27 minutes later each night, thus providing light for the farmer to continue gathering crops, even after the Sun has set.

The reason for this seasonal circumstance is that at this time of the year, the path of the Moon through the sky is as close to being along the horizon as it can get. Thus, from night to night the Moon moves more horizontally than vertically and thus rises sooner from one night to the next.