It's a sacrifice to the water gods to stop the rain.
Maybe there's a kraken like sea monster a-lurking in there. I knew I should have hung about to watch what happened next.
Anyway, I've obviously offended the water gods... last time but one I went out it was cold, windy and unpleasant, this time it poured down. Record breaking hot sunshiny days, gentle breeze and flat seas any other time at the moment...