Stuart Thompson, from the RNLI, says one of the risks of tombstoning is the sheer unpredictability of the environment.
"The problem is that you know heights of tides change, conditions change" he says.
"The conditions of the seabed change as well so it's actually quite a dangerous practice".
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There was disappointment for Swansea City after they lost to Manchester City for the second time in a week.
Windy with outbreaks of heavy rain pushing across the area through the evening and first part of the night.
Today will be bright, breezy and dry for most and rather windy in the northwest.