The average national temperature for January 2025 was 5.37°C, which according to Met Éireann is 0.45°C below the most recent 1991-2020 long-term average (LTA).

Overall, Met Éireann is saying that January was cool and rainfall varied from dry in the north and northwest to progressively wetter towards the south and east.

Early in the month, high pressure to the west allowed a cold arctic air mass to sink south over the country, which remained in place for the first third of the month.

Low pressure

Low pressure to the southwest pushed weather fronts northwest into the cold air mass over Ireland and brought heavy snow to the south midlands, south, southwest and west on Saturday 4 and Sunday 5 January, while the east saw heavy rain.

High pressure developed to the southeast and brought milder, drier and cloudier conditions for the second third of the month.

The final third was dominated by a powerful Atlantic jet stream, which steered several active low pressure systems towards western Europe, one of which was storm Éowyn.

Another system, named storm Herminia, became slow moving as it passed over the country between Sunday 26 and Tuesday 28 and brought further wet and windy spells. The month finished quieter, as pressure rose to the south.

Rainfall

Provisional rainfall data suggests January 2025 averaged at 116.7mm, which is just 88% of the LTA.

The majority of monthly rainfall totals across the country were below average. The lowest monthly percentage rainfall was 47% (57.7mm) of its LTA at Athenry, Co Galway. In contrast, the highest was 173% (165.3mm) at Roches Point, Co Cork.

Monthly rainfall totals ranged from 57.7mm at Athenry to 198.8mm at Valentia Observatory, Co Kerry.

Met Éireann also said that rain days ranged from 13 days at Dublin Airport to 27 days at Belmullet, Co Mayo.

Meanwhile, Johnstown Castle, Co Wexford, had its wettest January since 1998 with 153.8mm.

Wind

Storm Éowyn brought hurricane-force winds and new wind speed records for Ireland.

On Friday 24 January 2025 during storm Éowyn, the provisional highest (sustained and gust) wind speeds in the digital climate record for Ireland were reported at Mace Head, Co Galway.

The highest gust was 99.5 knots (184km/h), while the highest 10-minute mean wind speed was 76.5 knots (142km/h).

Four stations broke their highest gust records - Mace Head, Co Galway, and Finner, Co Donegal, with 150km/h (81 knots); Athenry with 139km/h (75 knots); and Gurteen, Co Tipperary, with 124km/h (67 knots).

Two stations reached hurricane force 12 on the Beaufort wind scale.

Four stations reached violent storm force 11 and eight stations reached storm force 10 on the Beaufort wind scale.