Storms blow in from the Atlantic without a moment’s notice, drenching the land and then leaving before you know what hit you. Rain can fall in thick droves, which the Irish refer to as “lashing,” or it can fall in fine mists that give way to dazzling rainbows. It can “spit” rain, where a few isolated raindrops fall, or it can “shower,” lasting only a few minutes and often occurring when the sun is shining. Only when it is a steady downpour of rain, worthy of a brolly (an umbrella), do the Irish classify it as true rain. All of this rain is due to Ireland’s oceanic climate, which is ruled by the Atlantic Ocean. This means the temperature across the island remains fairly moderate throughout the year, dominated by rain that is accumulated from the ocean. But this rain is what keeps the grass a lush green and the temperamental sea off its coast a deep, steel blue.
However, the weather in Ireland can also be quite changeable, so even if you awaken to clouds and rain in the morning, you are likely to see at least a peekaboo sun, especially during the summer months. On the flip side of this, don’t be fooled by bright morning sunshine, as the clouds and rain can roll in and start lashing at any second. Storms blow in from the Atlantic without a moment’s notice, drenching the land and then leaving before you know what hit you.
Even still, while most foreigners have the impression that it rains nonstop in Ireland, two out of three hourly observations do not have any measurable rainfall at all, according to The Irish Meteorological Service. Rainfall varies greatly, depending on the area of the country you are in. The average hourly rainfall in Ireland ranges 0.04–0.08 inch (1–2 millimeters). Much of the eastern half of Ireland receives 74–99 centimeters (29–39 inches) of rain a year, while the traditionally wetter west of Ireland receives 99–124 centimeters (39–49 inches) a year.
Temperatures in Ireland rarely get below 0°C (32°F) in the winter, although there have definitely been exceptions to this. When the weather does turn freezing or even a sprinkling of snow falls, the country typically grinds to a halt and people panic. Generally, however, the temperatures hover right around 4–10°C (40–50°F). In the summer months the temperature is typically between 16–21°C (60–70°F), with July and August being the warmest months, and May and June the sunniest months.
Excerpted from the Second Edition of Moon Living Abroad in Ireland.