Rip tide and currents warnings have been issued by Aberdyfi Coastguard during national drowning prevention week.
The initiative, which aims to remind people about the hazards of swimming in seas, lakes and rivers, began on Saturday (17 June).
The coastguard said: “Rips are strong currents running out to sea which can quickly drag you out of your depth.
“Sometimes they reach speeds faster than an Olympic swimmer, so it might not be a surprise that they’re a major cause of accidental drowning on beaches worldwide.
“We have our fair share between Aberdyfi and Tywyn, so this is very relevant.”
The coastguard posted an image which is aimed at helping people spot rip tides in the water – as they are often difficult to identify.
The image produced by Dr Rob Brander using dye shows the path of the currents and where to aim to escape them.
Anyone caught in a rip tide should not go against it and instead swim parallel to the shore.
His advice reads: “If you can: always choose a patrolled beach, swim between the yellow and red flags, and take advice from the lifeguards to help you identify and avoid rips.
“To break the grip of a rip: don’t try to swim against it or you’ll get exhausted.
“If you can stand, wade don’t swim.
“If you can, swim parallel to the shore until free of the rip and then head for shore.
“Raise your hand, shout for help.”
It also warned against hoax callers after it was called at 2am on 18 June to assist Barmouth Coastguard Rescue with reports intoxicated male in the water off Barmouth beach.
It added: “North Wales Police and Barmouth Lifeboat were also involved. The call was made from an emergency phone on the prom, and further investigation found it was a hoax call.
“Hoax calls prevent emergency teams being able to respond to genuine emergencies and drain resources.”
If you see anyone else in trouble, call 999 and ask for the coastguard.