Temperatures may again exceed 30 degrees on Friday, as the heatwave continues to bring hot and sunny conditions.
A status yellow temperature warning for the entire country comes into effect at midday and will remain in place until Sunday, with hot, dry and sunny days forecast for the weekend.
Met Éireann said highest temperatures will generally be between 25 and 30 degrees on Friday, with the possibility of reaching low 30s in a few inland spots around Leinster and Munster.
Meanwhile, coastal areas will not be as warm with sea breezes developing in the afternoon, and light winds appearing elsewhere.
Temperatures will increase further on Saturday, with highs of between 26 and 31 degrees forecast, but with the mercury potentially rising higher than that in a few parts of Leinster and Munster.
There is a chance of an isolated shower developing, the national forecaster said.
It will remain hot for the rest of the weekend, but temperatures will begin to fall back to more seasonal highs early next week.
There will be scattered showers on Sunday which will mark the start of more changeable conditions for the week ahead.
Irish Water said there are currently 24 supplies affected by shortages and the utility has implemented a range of measures such as tankering or night-time restrictions to protect supplies.
In addition, there are approximately 60 supplies around the country that are being closely monitored by Irish Water to ensure that normal supply is maintained for the rest of the summer and into autumn.
The National Parks and Wildlife Service (NPWS) has appealed to members of the public to be conscious of the risks posed by fire, adding that recent similar hot weather conditions resulted in “increased fire activity associated with public recreation activities”.
Malcolm Noonan, Minister of State for Heritage, said: “Don’t light fires or barbecues, keep access roads clear for emergency vehicles and if you’re camping, let someone know where you’ll be.”
Meanwhile, new research from the Irish Cancer Society found one third of people underestimate the threat posed by the Irish sun and are “not at all worried” about sunburn in Ireland.
The survey, conducted by Core Research on behalf of the charity, also found that while just a third would apply sun cream regularly, nearly one in seven would never apply sun cream when in Ireland. This rises to one in five among men.
Kevin O’Hagan, cancer prevention manager with the Irish Cancer Society, said sun safety is “vital”.
“Even on cloudy days in Ireland, UV rays can damage skin cells. Taking steps like applying sunscreen, covering up by wearing a hat and sunglasses and seeking shade can reduce your risk of skin cancer,” he said.
“Knowing your local UV index is also important, as when the UV index is higher than 3, you need to protect your skin.”