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. Data for specific coordinates can be downloaded for in the Data Download page.
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.
- Average temperatures have increased by 0.8°C since 1900, an average of 0.07°C per decade.
- The number of warm days (over 20°C) has increased while the number of cold days has decreased.
- Increase in average annual national rainfall of approximately 60mm or 5% in the period 1981-2010 was observed, compared to the 30 year period 1961-1990.
- The largest increases are observed over the west of the country (below 0°C).
This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.