About three or four times a year (in the spring and the fall), the new or full moon coincides closely in time with the perigee of the moon—the point when the moon is closest to the Earth. These occurrences are often called 'perigean spring tides.' The difference between 'perigean spring tide' and normal tidal ranges for all areas of the coast is small. In most cases, the difference is only a couple of inches above normal spring tides.
Meet oceanographer Stephen Gill, NOAA's chief scientist for tides and currents. On September 28, 2015, a perigee and the full Moon occur on the same day. When this happens, stronger than normal tides will occur both a few days before and after. Perigean spring tides are often referred to as King Tides because the high waters along with seasonal weather effects have the potential to cause major flooding especially in low-lying areas.