Abertawe Bro Morgannwg University Health Board says many of the people it has been treating have cardiac problems or have suffered a stroke. Many are over the age of 85.
The health board says it has brought in extra staff, and put on extra beds, to deal to with its A&E departments being exceptionally busy.
It says most routine operations have been postponed.
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A pleasant end to the day with late evening sunshine for most. However, skies will soon clear and it'll turn chilly with light winds.
Three men have been arrested after an incident this morning in Cardiff. Two people are in a stable condition in hospital.
Pictures posted on twitter show an officer with a bandage around his head and blood on his neck