The RNLI is urging visitors to the Vale's coastline to check tide times as temperatures begin to warm up this week.
Lifeboat volunteers were called out to reports from the Cardiff Bay Barrage team of one person being possibly cut off by the tide at Penarth Head on Monday night.
The D-class lifeboat was launched at shortly after 8.20pm - but after two searches of an area between the lifeboat station and the barrage, no person was found and the lifeboat was stood down.
The RNLI crew was allso called out on Sunday lunchtime to help a motorboat after it ran aground off Cardiff.
The crew extended the boats anchor, before carrying out a welfare check on the crew.

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