Temperature readings of 30 degrees were recorded at two weather stations, according to Met Éireann.
The national forecaster said that this number was recorded at Casement Aerodrome in Co Dublin, and Oak Park in Co Carlow, marking the fourth consecutive month that a primary station has reached the 30 degree mark in Ireland.
Prior to this, the longest run recorded was two months, in both 1976 and 2022.
This comes as a Status Yellow High temperature warning was put in place for both Leinster and Co Tipperary, a warning which has come into effect from 6am and remains valid until 6am on Friday. Temperatures are expected to surpass 27C during the day and 15C at night.
People have been warned about issues like heat stress, uncomfortable sleeping conditions, water safety issues from the rise in use of beaches, lakes and rivers, as well as animal welfare issues.
According to reports in RTÉ, senior forecaster, Gerry Murphy has said the weather warning is as serious as those which were issued earlier in the summer.
"All heat warnings are basically the same, in that they are predicting temperatures in excess of 27 degrees by day and temperatures in excess of 15 degrees by night," he said "The other heat warnings that we issued earlier in the summer would have been very similar to this".
"It is equally as significant as all the others because people need to be aware of taking care of the sun and also stay hydrated, and it may cause heat stress to some vulnerable people at night".
Mr Murphy went on to explain that the main difference with the current warning and earlier weather alerts was that this one was shorter.
"In terms of precautions associated with high temperatures it's the same as before. The difference in this period of warm weather though is that it's very short," he said. "We had a prolonged period heatwave in a number of stations for between five and 13 days during July, whereas this is not really a heatwave, it's a short hot spell".
"This is for the rest of today, tomorrow and into Friday but then it cools down from Friday onwards". (All quotes according to RTÉ).
Gerry Murphy added that these temperatures are not unusual for this time of year, despite the Carlow station hitting a mercury reading of 34.4c.
"From a meteorological perspective, August is still in the summer. Statistically the three warmest months in Ireland are June, July and August", he said. "You can say that we don't often get these temperatures in Ireland anyway, but it's not unprecedented to have a warm August ... it's not a month that you couldn't expect to have potentially very high temperatures".
He went on to say that Friday is to see a drop in temperatures.
"The temperatures drop back to the high teens to low 20s on Friday and they stay that way through the weekend and next week. Those are more normal temperatures that you'd expect for this time of year," he said. "The weekend is largely dry apart from one or two showers.
"At the moment, it looks like Monday is the most likely day to bring us some significant rain". (All quotes according to RTÉ).
It was also confirmed that a water conservation order from Uisce Éireann would remain in place until August 26, with low rainfall levels leading to shortages with low reservoir levels.
