The spell of good weather is likely to continue throughout the weekend.
A spokesman for Met Éireann said current conditions will last until Tuesday, when it will revert to "typical Irish weather ... for this time of year".
He added: “The fine summery weather is set to continue all weekend, but there will be a gradual change at the start of next week.”
He encouraged people to make the most of the sunshine and also to be cautious, as the UV index will be quite high tomorrow and on Sunday.
Temperatures of 20 to 24 degrees are expected in certain areas today and tomorrow, with the east coast being slightly cooler due to onshore east-to-northeast breezes.
Today will be dry and sunny, with minimal cloud. Temperatures will drop to between eight and 11 degrees tonight.
Similar conditions are expected tomorrow. Sunday will see temperatures reaching the low 20s in many inland areas, but it will remain cooler in coastal regions.
The weather will become more unsettled from Monday onwards, with an increase in clouds across the country. Leinster and Ulster will probably remain dry for most of Monday, but outbreaks of rain are expected in Connacht and Munster.
Temperatures are likely to drop to the high teens on Monday and further decrease to the low to mid teens on Tuesday. Increased levels of rain are expected during the remainder of the week.