A couple of different factors go along with tonight's full Harvest Moon.

1) The peak occurs on Friday the 13th; which is often surrounded by superstition.
"It’s rare for a full moon to coincide with Friday the 13th. The last time the two events synced up across the entire nation was on Oct. 13, 2000. The next time will be on Aug. 13, 2049."

2) The moon is a "mini" Harvest Moon.
A Mini Moon "occurs when the moon is at its most distant point in its elliptical orbit around Earth, a point some 252,000 miles away that astronomers call lunar apogee. It will look a bit smaller and about 13 percent fainter than average" This is the opposite of a Super Moon.

"In the Northern Hemisphere, September’s full moon is traditionally called the harvest moon because it occurs close to the peak of the fall harvest season." Quotes from NBC news.