Climatology
This page presents Ireland's climate context for the current climatology, 1991-2020, derived from observed, historical data. Information should be used to build a strong understanding of current climate conditions in order to appreciate future climate scenarios and projected change. You can visualize data for the current climatology through spatial variation, the seasonal cycle, or as a time series. Analysis is available for both annual and seasonal data. Data presentation defaults to national-scale aggregation, however sub-national data aggregations can be accessed by clicking within a country, on a sub-national unit. Other historical climatologies can be selected from the Time Period dropdown list.
Observed, historical data is produced by the Climatic Research Unit (CRU) of University of East Anglia. Data is presented at a 0.5º x 0.5º (50km x 50km) resolution.
In Ireland, the highest rainfall occurs in the Western half of the country and on high ground, while rainfall decreases to the Northeast. The average annual rainfall is approximately 1230 mm, but totals in excess of 3000 mm may occur on high ground. The driest seasons are Spring and Summer, with an average of approximately 260 mm, while Autumn and Winter have averages of approximately 350mm. The driest months are April, May, June and July, with an average of approximately 80 mm each month. February, March, August and September have average rainfall totals of approximately 100 mm, while October, November, December and January have averages of approximately 130 mm.