Two men men have drowned in separate accidents in counties Donegal and Tyrone, and another man is presumed drowned in Co Tipperary.
The deaths mean ten people have died by drowning during the current spell of good weather.
A 24-year-old man died in a drowning accident in Co Donegal.
The young man got into difficulty while swimming in the sea near Ardara this afternoon.
Emergency services were called to the area shortly before 2pm.
The man was airlifted to Letterkenny General Hospital, where he was pronounced dead a short time later.
The body of the second drowning victim was recovered from a river in Co Tyrone.
Two men got into difficulty in the Shrule River in Newtownstewart shortly after 5pm
One of the men was rescued and he was treated at the scene for non-life-threatening injuries.
A 64-year-old man is also presumed drowned in a quarry near Carrick-on-Suir in Co Tipperary.
The man, who is from the locality and knew the quarry well, told relatives he was going swimming there this afternoon.
When he didn't return, the alarm was raised.
Meanwhile, gardaí say a woman in her 30s is in a serious but stable condition after another swimming incident this afternoon.
Emergency services were called to a location near Kilkenny city centre after a woman got into difficulty while swimming in the River Nore.
She received medical attention and her condition is said to be stable at present.
Yesterday a 19-year-old man lost his life in a drowning accident in County Kerry.
His body was recovered from Lough Leane in Killarney yesterday evening.
He had been out swimming with a friend when it is understood he got into difficulties.