3 ms·TIL. Thanks. So it's a phenomenon that occurs twice per month. That's not bad at all.by smnrchrds 5y agoTIL. Thanks. So it's a phenomenon that occurs twice per month. That's not bad at all.kqr 5y agoIn fact, the average time you'd have to wait for it is... a week.lttlrck 5y agonot something you'd want to rely on though - the obstruction could happen at high tide.