British Divers Marine Life Rescue Medics successfully rescued a 30ft long fin whale that was stranded in the Dee Estuary off Thurstaston.
The whale was became stuck on Friday morning on the outgoing tide.
The whale was floated on the incoming tide and started to swim strongly for itself heading out to sea during Friday afternoon.
The BDMLR continued to monitor the whale from land and from a safe distance by boat so as not to cause any stress to the animal that might cause it to restrand.
The BDMLR said: “The whale has now floated on the incoming tide and is beginning to swim for itself.
“Our team have managed to measure it more accurately at around 13.5m long, which is very close to the size that they are weaned and independent of their mother, so there may be some hope for this animal to survive by itself if it can find its way back out of the estuary.
“It is also in moderate body condition, which is helpful to its prognosis too.
“Our team will continue to monitor from land and from a safe distance by boat so as not to cause any stress to the animal that might cause it to restrand.
“The tide is still coming in for at least another couple of hours and this will give it more space to move around in and hopefully locate the open sea.”