A perigean spring tide occurs when the moon is new or full and closest to Earth
Around 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 planet. 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.
Original article: What is a perigean spring tide?