DURING JULY’S HEATWAVE the mercury rose above 30 degrees across many parts of Ireland with a temperature of 30.8 degrees recorded in Mount Dillon Co Roscommon, making it the hottest temperature recorded in the month of July since the weather station opened.

According to a climate statement on the month from Met Éireann published this week most weather stations recorded their hottest July since 2013.

Heatwaves lasting ten consecutive days between 16 July and 25 July were reported at six weather stations across the country.

High temperatures became the norm for July but this year they were even higher than average. Weather stations across the country recorded at least a 0.5 degree increase from the average July temperatures between 1981 and 2010.

Below-average rainfall was recorded in the west of the country across the month, with Malin Head, Co Donegal recording a dry spell of 22 days between 5 and 26 July.

The east, in contrast, experienced heavy downpours causing 173% of the average rainfall monthly rainfall to occur in July at Casement Aerodrome, Co Dublin.

The hot weather first emerged in Ireland through the presence of a weather system known as the Azores high.

The climate report noted the weather movements that brought the July heatwave into place:

“A hot and dry tropical continental air mass was drawn up from the southeast between the 17th and 25th as the high-pressure system intensified over Ireland and the UK blocking any Atlantic weather fronts from approaching. This led to heatwave conditions in many places.”

The unusual weather was exemplified through the recording of two tropical nights at Valentia Observatory, Co Kerry. Tropical nights are a very rare occurrence in Ireland as they require the temperatures to stay above 20 degrees throughout the night.

Status Yellow and Orange high temperature warnings were put in place throughout the country over the course of the heatwave.

The return to average July temperatures at the end of the month was a welcome relief for many. The report notes that “the final six days of the month brought a return to Atlantic westerlies and low-pressure with rain or showers on most days, heavy and thundery in places, and average temperatures.”

Further climate analysis studies will be carried out to determine the full consequences of July’s heatwave. Yet the impacts of the heatwave are already emerging, with the largest fish kill of the year linked to “very high” water temperatures recorded last month.

Due to the impact of climate change the occurrence of heatwave events looks set to become a more regular phenomenon.

Indeed Dr. Darren Clarke, Environmental Geographer at DCU, expects these trends to continue in the years ahead.

“The record temperatures that we are seeing in many parts of Ireland are likely to be broken again over the next couple of decades because we’re in the midst of a climate crisis,” he explains.

Research from Climate Ireland shows that since 1900, there has been an increase in the surface temperature here of 0.8 degrees.

It suggests that in the coming years, average surface air temperatures are expected to rise across Ireland during all seasons, with more intense and longer heatwaves.