Last month, the residents in the northern and northwestern regions of Ireland experienced much colder and heavier rainfall than those residing in other parts of the country, according to data procured by Met Éireann. Record-breaking rainfall for August was noted both at Malin Head in Co Donegal and Newport in Co Mayo. Markedly, Malin Head encountered rain on 29 days, as compared to Phoenix Park in Co Dublin which only had such days for half the period.
A day is officially classified as a ‘rain day’ when there is 0.2mm or more of recorded rainfall. August has been the second wettest month in Ireland’s recorded history and the rainiest since 1985.
The resident weather forecaster, Paul Moore explained that an individual’s geographic location has a profound influence on the weather one might encounter, even within a relatively small nation such as Ireland. He pointed out a significant variation in weather patterns between the northwestern and southeastern regions, drawing attention to the consistent trend towards warmer and wetter summers over two observable 30-year meteorological cycles.
Moore clarified that low pressure systems, carrying increased moisture, generally hovered over the north and northwest areas, losing strength by the time they reached the east and southeast. On a historical note, the previous month was noted as the 35th hottest since national temperature records were initiated 125 years ago.
Moreover, the mean temperature for August was calculated at 15.5°C, slightly higher namely by 0.20°C, than the most recent long-term average recorded from 1991 until 2020, 0.28°C higher than the figures for 1981 to 2020 and significantly warmer – by 0.79°C – than data from 1961 to 1990.
Preliminary rainfall information suggests that last month’s rainfall surpassed the long-term averages between 1981 to 2010 by 14 percent (equating to 117mm) and 13 percent more compared to the data recorded between 1991 and 2020.
In terms of precipitation, the northwest of the country experienced the largest amount of moisture, whilst the east and south witnessed the driest conditions. Rainfall compared to the Long-Term Average (LTA) from 1981-2010 varied across the nation. Dublin Airport, Co Dublin saw a meagre 36.6mm, equating to 50% of the monthly LTA – the minimum for the month. Contrastingly, Belmullet, Co Mayo endured a substantial 208.1mm, or 204% of its LTA, making it the rainiest August there since 1992. In Newport, Co Mayo, the precipitation reached a staggering 257.5mm, amounting to 194% of its LTA.
The variety in rainy day counts was also noteworthy. Both Phoenix Park and Casement Aerodrome in Co Dublin experienced a minimum of eight wet days. Conversely, Athenry, Co Galway was subjected to rainfall on 25 different days. The variance in the prevalence of very rainy days was considerable as well; ranging from none in Moore Park, Co Cork to as many as 13 in Newport, Co Mayo.
Newport also saw the most amount of rainfall in one day, with 34.6mm registered on Sunday 4th. Rainfall records for the month of August were broken at two stations. Malin Head, Co Donegal recorded 181.3mm, a record spanning 69 years and Knock Airport, Co Mayo marked 215.4mm, surpassing a 28-year record.
Temperature extremes for the month were observed in Casement Aerodrome, Co Dublin, with a peak of 24.3 degrees on Sunday 11th, and at Mount Dillon, Co Roscommon, recording a low of 3.5 degrees on Saturday 31st.