Met Eireann's issued a High Temperature Advisory with the warm weather set to continue into next week.
The advisory comes into effect from midday today and is valid until midday on Friday.
Temperatures reached 29.5 degrees in Athenry, Co Galway yesterday, making it the hottest day of the year so far.
Alan O'Reilly from Carlow Weather says today will be another warm day.
With the good weather staying with us for the week ahead the RNLI is urging people heading to beaches in the warm weather today to respect the water.
They say if you see anyone in difficulty in the sea call 112 or 999 immediately and ask for the Coastguard.
RNLI Head of Water Safety, Gareth Morrision, says people should stick to swimming near lifeguards.