A status-yellow temperature warning was put in place by Met Éireann from Thursday, with temperatures of up to 27 degrees forecast.
However, there is the possibility of isolated thundery downpours and spot flooding over the coming days.
Met Éireann put the status-yellow weather warning in place from 8am on Thursday until 8am on Saturday, due to “very warm and humid weather”.
“Daytime temperatures in excess of 27 degrees in many areas away from coasts with night time temperatures not falling below 15 degrees,” the warning states.
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The forecaster outlined some potential effects of the weather including heat stress, uncomfortable sleeping conditions and risk of water-related incidents.
On Thursday morning, the forecaster said, there would be spells of sunshine and scattered showers that would spread northwards over the country. The day will be more unsettled, and some of the showers are likely to be heavy and thundery, with the potential for spot flooding.
The afternoon will see plenty of warm sunshine and isolated heavy downpours, according to Met Éireann. Highest temperatures will generally range from 24 to 27 degrees.
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Looking further into the week, it is set to stay very warm and humid with sunny spells and occasional thundery downpours. Friday will be a warm day, with lots of autumn sunshine. A few heavy showers or thunderstorms may break out inland during the afternoon and evening, with maximum temperatures of between 24 and 27 degrees.
However, there will be a lot of mist and fog around on Friday night with well-scattered heavy showers or thunderstorms. Saturday will begin with a cloudy and misty morning, with isolated heavy showers.
Sunshine will develop in many areas during the afternoon but mist or fog may linger in some coastal areas. Further isolated heavy or thundery showers are possible.
Sunday will bring a mix of cloud, sunshine and showers, with highest temperatures of up to 24 degrees.
