RTE weather woman Joanna Donnelly has warned there will be "extreme uncertainty" over the coming days as Ireland is set to be hit with both cold air and the European heatwave.
Met Eireann have forecast temperatures to reach up to 26 degrees on Friday in parts of Leinster and Munster but it will only reach the mid-teens near the west and northwest coast.
Joanna explained this is because Ireland is "on the border" between a clash of cold air from the north and heat from the south.
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She said on Today with Claire Byrne: "The heat has been moving up through Spain and Portugal to France and it will head further north over the next few days, probably impacting the south east of England significantly over the weekend.
"We are faced with uncertainty over the next few days. We are on the border between very cold air coming down from the northwest from the Arctic and this heat coming up from the south.
"The two of those are extremes, so extreme heat and quite cold weather.
"Ireland is in prime position in north of the Atlantic and is right on the border for those two.
"With those extremes comes extreme uncertainty."
Joanna said current forecasts suggest that Friday will be "right on that border".
"We don't know how far south the cold air will get, we don't know how long the warm air is going to last or proceed up northwards the country," she said.
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"At the moment it looks like Friday will be right on that border. We'll have heat in the south east of the country and temperatures possibly getting up to 26 degrees.
"That cold air is coming down and with cold air means warm air rises and it turns into cloud and we get rain.
"And that rain then is the uncertain line where it's going to get on Friday."
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