Met Éireann has issued a yellow weather warning for high temperatures on Sunday, Monday and Tuesday.
Daytime temperatures of 25 to 30 degrees are expected generally and possibly higher in places on Monday with night-time temperatures ranging from 15 to 20 degrees.
The incoming heatwave could result in Ireland’s hottest day since records began, with some models suggesting temperatures as high as 34 degrees on Monday.
The highest recorded temperature in Ireland of 33.3 degrees, which was recorded in Kilkenny on June 26th 1887, has stood for 135 years.
The national forecaster warned people of heat stress. water-related incidents and a high solar UV index.
The latest models from the Global Forecast Systems (GFS) and ICON-EU, the German weather service, show temperatures breaching the 33 degrees mark in parts of South Dublin and north Kildare, Galway, Limerick and around the Foynes estuary in Co Clare on Monday.
The UK-based independent weather service, Netweather, has values of 34 degrees in the south midlands.
The European Centre for Medium-Range Weather Forecasts (ECMWF) has highs of 32 degrees plus on Monday for the south midlands.
The Met Office issued a red warning for parts of England on Monday and Tuesday with temperatures expected to reach up to 40 degrees in certain parts.
Met Éireann forecaster Paul Downes said it was “not out of the realm of possibility” that the all-time record temperature for Ireland could be broken. He said it was certainly possible that the record temperature for July of 32.3 degrees recorded at Elphin, Co Roscommon on July 19th, 2006 will be breached.
“We are keeping a more cautious look at it, but it could get up to 33 or 34 degrees,” he said.
The record-breaking temperatures is being driven by a hot air mass from north Africa which is bringing 40 degrees plus temperatures to Spain at present.
Weather models show temperatures breaching 37 degrees (100 degrees Fahrenheit) on Monday in London with temperatures in England reaching 40 degrees for the first time in recorded history.
The hottest days will be Monday and Tuesday but then conditions are expected to deteriorate with showers and thunder on Tuesday night.
Coincidentally a new academic paper has disputed the 33.3 degree figure recorded at Kilkenny. Students at the Irish Climate Analysis and Research Unit (ICARUS) state that Ireland is an outlier in terms of having the hottest temperature recorded in the 19th century.
France, Belgium, Netherlands, England, Scotland and Northern Ireland have seen record-breaking temperatures in this century.
The paper, which is in being published in the European Geosciences Union — Climate of the Past journal, is authored by master’s students at ICARUS which is based in Maynooth University.
They claim the temperature is inconsistent with those observed at Birr Castle in Co Offaly, Markree Castle in Co Sligo and Sheffield in England or to the general forecast as observed on that day.
Nine of the 10 highest temperatures in Ireland were recorded in the 19th century. The ICARUS students maintain there is “grossly insufficient evidence” to support these temperature values given the nature of the equipment used in those days.
Maynooth Professor of Geography (climate change) Peter Thorne said there has long been questions over the Kilkenny temperature records as the records themselves no longer exist.
“The differences between Kilkenny and all surrounding stations constitute either an incredibly extreme outlier or lie entirely outside the range of differences seen in more modern observations for these sites. There is ... no physically plausible way that the Kilkenny observation that day could be correct,” he said.
“I would stress as is done in the paper that the official recognition rests with Met Éireann. They will have to decide whether to scrub the record.” Mr Downes said Met Éireann stood by the record.
The ICARUS scientists posit that the highest verifiable temperature recorded in Ireland was the 32.5 degrees recorded on June 29th at Boora, Co Offaly during the long, hot summer of 1976.