County Louth climate

Monthly averages for Dundalk, 2021–2025 · Leinster

Louth, the smallest county, is on the east coast and among the driest in Ireland. The Cooley Mountains in the north catch more rain, while the coast from Drogheda to Dundalk is sheltered and relatively sunny.

Rain: about 1063 mm falls in a year at Dundalk, on roughly 172 days, making Louth the 23rd wettest of the 32 counties. October is the wettest month (126 mm) and January the driest (64 mm).

Temperature: July is the warmest month, with afternoons averaging 19°C, and January the coldest, with nights averaging 2°C. Frost is rare.

Sunshine: about 2524 hours a year, the 7th sunniest of the 32 counties. June is the sunniest month (10.5 hours a day) and December the dullest (3.0).

Compare Louth with its neighbours →

Rainfall

Average total rainfall each month, in millimetres. 1063 mm a year.

Temperature

Bars run from the average night-time low to the average daytime high, in °C.

Sunshine

Hours of sunshine on an average day in each month. About 2524 hours a year.

Louth and its neighbours
County	Rain mm/yr	Rain days	July high	January low	Sun h/yr
Louth	1063	172	19°C	2°C	2524
Meath	978	169	20°C	2°C	2506
Monaghan	1064	185	19°C	2°C	2375
Armagh	1008	177	19°C	2°C	2433
Down	1071	168	18°C	3°C	2679

Recent extremes, 2021–2025

Hottest day: 27.3°C on 17 July 2021
Coldest night: −5.4°C on 9 January 2021
Wettest day: 44.5 mm on 21 July 2025
Wettest month: September 2022, 170 mm
Driest month: March 2025, 17 mm

Ireland's all-time records are on the records page.

Dundalk month by month
Month	High °C	Low °C	Rain mm	Rain days	Sun h/day	Wind km/h
January	7	2	64	12	4.0	14
February	9	4	76	13	4.3	17
March	11	4	84	15	6.3	14
April	12	5	82	16	8.7	13
May	15	8	74	15	10.4	12
June	18	11	76	14	10.5	13
July	19	12	90	15	9.4	12
August	19	12	84	14	9.4	13
September	17	10	115	14	7.4	13
October	14	9	126	17	5.2	15
November	11	5	90	15	4.2	15
December	9	4	102	14	3.0	16
Year	13	7	1063	172	2524 h	14

Figures are averages for 2021–2025 at each county town, from the ERA5 weather reanalysis via Open-Meteo. They describe typical lowland weather in each county; hills and exposed coasts are wetter and windier.

Bordering counties: Meath · Monaghan · Armagh · Down. All counties: rainfall, temperature, sunshine.