Top temperatures today will range from 18C to 22C. Early tonight will see long clear spells but cloud will thicken from the south overnight with rain developing in Munster and south Connacht before dawn. Minimum temperatures of 10C to 14C are expected overnight.
Met Éireann has issued a 22-hour yellow rainfall alert from 2am on Sunday morning until midnight.
"High amounts of rainfall may cause some disruption and spot flooding, with highest amounts in mountainous areas,” the forecaster said.
The warning comes as thousand of country music fans will descend on Croke Park on Sunday evening, to see Garth Brooks’ perform at his third Irish concert of the weekend.
Met Éireann said rain will extend nationwide on Sunday morning, turning heavy and persistent in places. Isolated thundery downpours are possible along with the potential for localised flooding. It will be humid and breezy on Sunday with highest temperatures of 17C to 20C.
Further outbreaks of rain are expected on Sunday night, with heavy downpours in places. It will be mild and humid overnight with lowest temperatures of 12C to 16C.
On Monday, patchy rain and drizzle will become largely confined to the southeast of the country with sunny spells developing elsewhere. Met Éireann said top temperatures will range from a “rather fresh” 15C or 16C in the north to 20C or 21C in the south.
It will be mostly dry on Monday night, with long clear spells and the chance of a few showers in the northwest. Lowest temperatures will drop back to between 7C or 10C.
The forecaster said Tuesday looks mainly dry with long spells of sunshine and highest temperatures ranging from 16C to 20C, warmest in southern counties.
It will continue mainly dry overnight with long clear spells and lowest temperatures of 6C to 9C.
Wednesday is expected to be another dry day, with sunshine and highest temperatures of 16C to 20C.
Wednesday night will remain mostly dry, with clear spells and lowest temperatures of 6C to 10C.
"Early indications suggest high pressure will build near Ireland bringing mostly dry and settled conditions for the remainder of the week,” Met Éireann said.