The year 2016 saw enhanced Perseid activity attributed to Earth passing through separated dust trails from Comet Swift–Tuttle before 2026.
The Perseids can vary considerably from year to year because the comet’s debris is not distributed evenly along a perfectly smooth stream. In 2016, observers recorded enhanced activity associated with passages through separated dust trails left by Comet Swift–Tuttle.
This is different from the shower’s ordinary annual pattern. The Perseids return every year because Earth repeatedly crosses the stream, but individual trails and denser filaments can temporarily raise meteor rates above the usual background.
The International Meteor Organization also notes reports of high activity well after the main peak in 2018, 2020, and 2021. Such variations show why meteor forecasts provide expected timing and rates rather than guaranteed counts for every location.