The Atlantic multidecadal oscillation (AMO) which relates to the North Atlantic sea surface temperatures, explains over 90% of the pronounced decadal variation in annual land temperatures and summer precipitation- Met Eireann, 2015.
This clearly shows that the AMO and mean annual land temperatures over Ireland are in phase i.e. when decadal averages are considered mean temperatures over Ireland are warmer when the North Atlantic ocean is warmer than average. Mean summer rainfall over Ireland is also correlated to the AMO, with drier summers on average when the AMO is in a negative phase.
Understanding the impact of these ocean variations when interpreting long climate records, particularly in the context of a changing climate, is crucial.
So in general, when Ireland has warm temperatures, the AMO is in positive phase, and vice versa.
Heavy rains in summer are mostly driven by a positive AMO and drier summers occur mostly during negative AMOs. Presumably, the hotter weather causes more evaporation over the oceans, and therefore, more rain.
This means that we should be seeing colder, drier weather in Ireland in the coming years as the AMO moves to it's negative phase. This should see an upsurge in demand for heating fuel and electricity and an impact on harvests.
The full article can be read here : http://mobile.met.ie/news/display.asp?ID=330 and https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/wea.2543