July 2023 Breaks Rainfall Records in Cork and Ireland
July 2023 will go down in history as the wettest July on record in Cork and Ireland, according to provisional figures released by Met Eireann. The month was characterized by relentless rain, with barely a day passing without significant rainfall in Munster. In fact, Cork and Munster saw four times as much rain in July 2023 compared to the same month in 2022. This comes after a near record-setting June for sunshine and temperatures, making the contrast even more striking. However, there is a glimmer of hope as the weather may be improving.
Aside from the heavy rain, July also brought unusually low temperatures, cold nights for high summer, frequent thunderstorms, and regular spot flooding. While Cork has experienced wet and cold summers in the past, including in 1979, 1985, and 1997, this year’s weather has been particularly severe. Unless August brings a significant turnaround, which currently seems unlikely, 2023 will be remembered as one of the worst summers in a century.
Met Eireann’s data for July reveals that Ireland had 217% of its 1981-2010 Long term Average (LTA) rainfall, making it the wettest July on record. Compared to July 2022, July 2023 had more than four times the amount of rain and more than double the amount observed in July 2021. The previous wettest July was in 2009, with 202% of the LTA rainfall. Over the past 12 months, Ireland has experienced record-breaking rainfall in October 2022 and March 2023, in addition to the recent July downpour.
Seventeen primary weather stations across Ireland reported rainfall in excess of 200% of the normal average for July. While this was observed in most parts of the country, the station with the highest above-average rainfall in Cork was Moore Park, located outside Fermoy in North Cork. It received a soggy 150mm of rain, which is 242% of its average and a record-breaking amount.
The highest daily rainfall total in July 2023 was 41.6 mm, recorded at Dunsany, Co Meath on Saturday 22nd. This was closely followed by 41.2 mm at Oak Park, Co Carlow on Monday 10th. In comparison, the highest daily total in the previous wettest July in 2009 was 68.5 mm at Caherkirby, Co Cork.
The persistent wet weather can be attributed to a continuous succession of Atlantic low-pressure systems, predominantly moving in a westerly or cyclonic airflow. Ireland found itself on the cooler northern side of the North Atlantic jet stream for most of the month, which was unusually strong for this time of year. Met Eireann explains that numerous active weather fronts crossed the country, bringing intense, sometimes thundery, convective rainfall.
While Ireland experienced low pressure and cool air masses, southern Europe was dominated by blocking high pressure. This inhibited cloud formation and allowed extreme heat to build up in those regions. Unfortunately, major changes in the weather pattern are not expected in the near future. Met Éireann’s latest monthly forecast predicts that the current meteorological setup will continue into the early days of August, with the North Atlantic jet stream remaining south of the country and low-pressure systems continuing to dominate our weather.
In conclusion, July 2023 will be remembered as a month of relentless rain and below-average temperatures in Cork and Ireland. The records broken this year highlight the severity of the weather, with four times the normal amount of rain falling compared to the previous year. While there may be some improvement on the horizon, the current weather patterns are likely to persist into August.