October much warmer and wetter than normal

As the mild weather continues, Met Éireann has confirmed that last month the air temperature at Malin Head was 1.2 °C degrees above the Long-Term Average (LTA).

"Deviations from mean air temperature ranged from 1.2 °C (11.9 °C mean temperature) at Malin Head, Co. Donegal to 2.2 °C at both Dunsany, Co. Meath and Casement Aerodrome, Co. Dublin (11.8 °C and 12.2 °C mean respectively),” Met Éireann said.

All rainfall totals were above their 1981-2010 LTA and Donegal had most rainy days.

"The highest daily rainfall total was 54.9 mm at Cork Airport, Co Cork on Sunday, October 16, (its highest daily value for October since 1995).

"The number of rain days ranged from 20 days at both Dublin Airport and Casement Aerodrome, Co. Dublin to 30 days at Finner, Co. Donegal,” said Met Éireann.

Sunshine totals were above average were comparisons were available but this was not the case in Donegal, which recorded the lowest amount of sunshine.

"Monthly sunshine totals were lowest at Malin Head, Co. Donegal with 71.6 hours,” Met Éireann confirmed.

Meteorologists characterised October as ‘a very mild and wet month’ dominated by Atlantic low pressure.

"The first half of the month saw low pressure to the north and northwest of Ireland, steering several Atlantic weather fronts across the country from the west and southwest, interspersed with sunny spells and showery periods.

"Active weather fronts brought widespread heavy rain on the 4th, 5th and 9th, with the bulk of the rain in the West.

"A semi stationary trough of low pressure stalled to the southwest of Ireland for the second half of the month. This steered up numerous active weather fronts and surface low pressure systems from the south and southwest, which brought widespread spells of heavy and often thundery rain, interspersed with bands of heavy and often thundery showers, with the South, East and Midlands worst affected during this period,” the forecasters at Glasnevin observed.

Further active fronts brought heavy rain on October 15 and 16, with flooding in the South.

"A deep area of low pressure to the southwest of Ireland, named storm Armand by Portuguese weather service, steered up a very warm and moist air mass from the southeast over Ireland, which brought some very active thunderstorm activity and heavy rain on the 19th, especially in the South and East.

"Active weather fronts brought widespread rain on the 22nd and 23rd, with further falls of heavy rain on the 28th and 31st, especially in the Midlands and South,” said Met Éireann.

The Armagh Observatory reported the wettest October at Armagh for 11 years and probably the fourth-wettest October since daily rainfall records began in 1838.

The Observatory stated: “Total measured precipitation was 149.45 mm (5.88 inches) including one trace value, that is, 149.4 mmm if trace values are ignored.

"This is nearly 86% more than the 183-year long-term (1838-2020) average October precipitation at Armagh (80.4 mm) and 85% more than the most recent (1991-2020) 30-year average (81.0 mm).

"Three of the five wettest Octobers at Armagh since 1838, namely October 1870 (193.75 mm), October 2011 (182.75 mm), October 2002 (158.10 mm), October 1865 (150.0 mm) and October 2022 (149.45 mm), have occurred in the last 20 years.”

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