Met Éireann has issued a warning over "exceptionally" high temperatures this weekend and into next week.
On Sunday, Monday and Tuesday "exceptionally warm weather" will occur over Ireland with daytime temperatures of 25C to 30C generally and possibly up to 32C in places on Monday.
Met Éireann said it will remain uncomfortably warm overnight too with night-time temperatures ranging from 15 to 20 degrees.
Issuing a Yellow weather warning nationwide, it said there was a risk of water-related incidents, an impact of heat stress especially for more vulnerable people, and a high UV index.
The warning comes into effect from 6am on Sunday and lasts until 9pm on Tuesday.
Over the next few days a combination of factors will steer the high temperatures seen in Europe to Ireland for a brief spell, according to Met Éireann's operational meteorologist Paul Downes.
He said the high temperatures are caused by a portion of the Azores High extending from the southwest over Ireland for the weekend, bringing rising temperatures but still holding warmer air to the south.
Writing in his meteorologist's commentary, Mr Downes said as the high pressure moves away to the east it will also steer up air from the southeast.
"The cyclonic or anticlockwise flow of the low working in conjunction with the anticyclonic flow from the high will generate a strong surge of warm air between both systems thus pushing the warm air towards Ireland, transporting the air mass that has brought exceptional temperatures to Europe, towards Ireland," he said.
Over today and tomorrow temperatures will generally range in the low-to-mid 20s, Some upper cloud will sometimes make sunshine a little hazy and there is a chance of showers too.
Temperatures will rise into the upper 20s for Sunday and possibly above 30C for some locations on Monday.
"There is a little more uncertainty regarding Tuesday but it does look like it will be another hot day and perhaps as hot if not hotter than Monday," Mr Downes said.
People are advised to cover up, wear SPF protection, seek shade, and stay hydrated.
The warmer air also brings a chance of a few thundery bursts, "especially on Tuesday".
Night-time temperatures will also be warm and humid, with temperatures on Sunday and Monday night possibly not falling below the mid-teens.
"In some areas they may not fall below 20°C, which is known as a tropical night," Mr Downes said.
The breakdown of the system is expected over Tuesday or Wednesday, with a low-pressure system steering in cooler air and wet conditions.
Over recent decades we have observed an increase in the frequency, duration and intensity of extremely hot weather across most global land regions, Mr Downes said.
Human-caused climate change resulting from greenhouse gas pollution is the main driver of this increase in extreme heat.
"While extremely hot weather does occur within natural climate variability, the kinds of temperature extremes we are seeing in Europe are directly influenced by climate change," he wrote.
"June 2022 was Europe's second warmest on record, and the USA's warmest. The eight hottest Junes on record globally all occurred in the last eight years," he added.
Keith Lambkin, Head of Met Éireann’s Climate Services Division said: "Due to climate change, we are expecting to see heatwaves become longer, more frequent and intense than in the past. This increase in heat, increases the odds of temperature records being broken."
The highest ever temperatures recorded in Ireland were 33.3C at Kilkenny Castle on 26 June 1887, followed by 32.3C in Elphin, Roscommon on 19 July 2006.
Meanwhile, Water Safety Ireland has appealed to people to stay safe in the water during the hot weather.
It has advised people to stay within their depth, and to swim between the red and yellow flags at a lifeguarded waterway. IWS also said that alcohol is a factor in one third of drownings, and that people should not mix alcohol with water activities.