Warnings have been issued over the homeless, vulnerable neighbours and the elderly
Temperatures are expected to hit 27C today.
A yellow high temperature warning is in place nationwide with the country expected to officially enter a heat wave this week.
The high temperatures mean we could be experiencing the hottest summer in Ireland since the seventies.
The Minister for Health Simon Harris has urged the public to check in on elderly or isolated neighbours - and make sure babies or children aren't left alone in cars.
Meanwhile, people are being urged to take extra care when swimming in rivers, lakes and the sea
Met Éireann forecaster Pat Clarke told Newstalk that a warning like this is rare for Ireland:
“Basically temperatures are going to continue to rise this week,” he said.
“Around 27C degrees or so today and it is going to be in the high 20s in subsequent days. It is a rolling kind of a warning; it will be updated every day.
“But just to flag that it has been warm – but it is going to get warmer.”
He said temperatures will hit 27C today, adding that “there is no obvious end in sight.”
“Temperatures in parts of Ulster and Connacht may go back a few degrees over the weekend but we are still looking at temperatures well into the 20s over next weekend.”
Homeless charities meanwhile say soaring temperatures could pose a risk for rough sleepers.
Inner City Helping Homeless says it will have teams out on the streets during the daytime this week and outreach teams will be out every night as normal.
CEO Anthony Flynn says they're worried about people stranded outside without shelter, as well as families in emergency accommodation.
Please let us know if you see a person sleeping rough during this #heatwave by using the link below. #housingfirst teams are stocked up with water etc & are out in Dublin now ready to respond to your reports. Thank you! https://t.co/Gr24ICTua9 pic.twitter.com/Bpb9Du8lnu— Homeless Dublin (@HomelessDublin) June 24, 2018
“Normally we would be warning in regard to cold weather," said Mr Flynn. "But we are fortunate enough this week that we have a lot of hot weather."
"There is grave concern for the individuals that are on the street and spending excessive amounts of time on the street – so rough sleepers and homeless people.”
“At the moment we are looking at putting hydration teams together to make sure that people on the streets are being hydrated.
“There is a fear of dehydration and of course sunstroke for people that are spending excessive amounts of time on the street."
Pet owners are being advised to walk their dogs early or late in the day to avoid heatstroke, and use sunscreen on cat’s ears to avoid burning.
The Department of Agriculture has an orange fire warning in place and the HSE has issued essential heatwave advice as temperatures continue to soar.
If you're working outside in the sun, you need to wear sun-cream, take breaks, and stay hydrated.