Members of the public have been urged to look out for the vulnerable and take care in the heat, with temperatures set to rise into the high 20s.
A weather advisory for the whole country has been issued for hot temperatures over the coming days.
The advisory will remain in place until Monday, August 15.
According to Met Éireann, Ireland will experience a hot spell developing from Wednesday and continuing through the week and the weekend.
It is expected that daytime temperatures will reach the mid- to high-20s and will remain uncomfortably warm overnight.
The forecaster will monitor the situation and provide updates throughout the heatwave.
Monday will see long spells of sunshine with the chance of a shower in the northwest. Temperatures could reach the mid-20s during the day.
Spells of hazy sunshine will continue throughout Tuesday with light winds and temperatures between 21C and 24C.
Then on Wednesday, when the hot spell is expected to begin, people will enjoy a fine day with prolonged sunshine as the mercury creeps up to around 26C.
There will be little change on Thursday and Friday as the country will bask in hot sunshine with temperatures hitting the high 20s, leading into warm and close nights with temperatures only dipping to 15C to 19C.
The high pressure is expected to stick around for the weekend bringing mostly dry weather, sunny spells, and well-above-average temperatures.
Met Éireann weather forecaster Conall Ruth said the current region of high pressure over the country has meant largely clear skies as well as very light winds.
“During the day that allows the sun to shine through and really heat up the land and the air above it," he told RTÉ radio.
“What we're also going to see over the coming days is that high pressure tracking away to the east — towards Denmark and beyond. And as it does so the air flow around that high pressure will also draw up a lot of warm continental air from mainland Europe that will also contribute a lot to the very warm temperatures that we're expecting.”
While there was some uncertainty about exact temperatures, he said the hottest temperatures are expected to persist right through the weekend. The nights will also be a good bit warmer than average especially from around Thursday night onwards with temperatures not really falling below the mid-teens.
“Generally the southeast of the country is expected to see the highest temperatures over the coming days, but the Midlands will also get very hot as we head through the weekend and it will stay coolest near western and north-western coasts.
"But based on current projections all areas can expect to see temperatures reach at least the low-20s over the weekend.”
When asked if this predicted heatwave was the result of global warming, Mr Ruth said it was difficult to attribute any single event to climate change, “but certainly spells of hot weather like this are something we are seeing more frequently as we continue to change the climate and that's really going to continue as we move forward.”
The public is urged to take care during the hot spell as UV levels will be high, especially under clear skies.
There will be a risk of heat stress, particularly among the more vulnerable in our communities.
Mr Ruth cautioned the public to look out for the elderly and the vulnerable and also urged people to wear sunscreen, to stay hydrated, to exercise caution when near water and to take care when using barbeques.
People are advised to wear appropriate clothing, seek shade during the hottest part of the day (between 11am and 3pm), wear sunglasses, and wear suitable SPF.
Adults are recommended to apply at least SPF 30 while children should be given SPF 50.
Those seeking to cool off by heading to the beach are reminded to respect the water.
If swimming, do so on a lifeguarded beach and do not go to secluded areas or places where it will be difficult to spot you.
Young children should not use inflatable toys in the sea as they can rapidly be swept away from the shore.
Kevin Rahill, RNLI water safety lead, said people should tell someone where you are going and what time you will be back.
“For those going afloat, wear a lifejacket or personal flotation device, and carry a reliable means of raising the alarm such as a VHF radio or mobile phone.
“Go prepared by checking the weather forecast and tide times, tell someone where you are going and what time you will be back, and importantly, what to do if you do not arrive back on time.
“Should you get into difficulty or see someone else in trouble, dial 999 or 112 and ask for the Coast Guard.”