28-05-2025
Is there such a thing as 'Leaving Cert weather'?
As generations of Irish people know, June means the start of the exam seasons - and that usually also means good weather. Indeed, it's a common scenario for Leaving Cert students to find themselves revising maths and trying to work out which Irish poet will come up in the midst of blue skies and sunshine. We talked to Met Éireann meteorologist Liz Gavin to find out if there really is a connection between the Leaving Cert season and good weather.
Do the weather records back up the popular notion of typical Leaving Cert weather for June?
The meteorological summer months (June, July and August) are the warmest months in Ireland. When we measure how warm, dry or sunny a month or season has been, it is in comparison with a standard reference period of 30 years that we compare it with.
Let's take a look back at the past seven years in Ireland in comparison to the climatological reference period 1961-1990. According to Dr Sandra Spillane from Met Éireann, "the last seven consecutive Junes in Ireland were all above their Long Term Average temperature, with June 2015 being slightly below normal. However while June is one of the warmest months of the year, it is usually not hotter than July.
From RTÉ News, Met Éireann forecasts good weather for the next week
Since we transition from the cooler meteorological spring months to our meteorological summer, it may feel warmer in the days of June around the time the Leaving Cert commences than if the temperatures had occurred at the end of the summer. You can find more details on the climate of Ireland here.
Is June usually the sunniest and driest month of the year weather-wise in Ireland?
"Because of the variation in length of day from winter to summer, the duration of sunshine has a marked seasonal variation." As a consequence December is on average the dullest month with the least sunshine and "normally May or June are the sunniest months in Ireland" according to Spillane.
Forecasting sunny weather is partly about observing what is not there, and that is of course the clouds. Forecasters also use their knowledge of atmospheric pressure to predict sunshine, along with satellite imagery which gives forecasters a picture of the sky from above and helps give greater detail about expected sunshine levels. The highest monthly total of sunshine hours that has been recorded for June in Ireland since 1942, was recorded in Rosslare, Co. Wexford in June 1959 with 301.0 hours of sunshine.
Although many of us may long for sunny weather, there are downsides also as sustained periods of dry and sunny weather can lead to dry periods. In Ireland, a climatological partial drought is a period of a least 29 consecutive days when the mean daily rainfall does not exceed 0.2mm and an absolute drought is a period of 15 consecutive days or more to which none are credited to 0.2mm.
Looking back at last summer, it was much drier than usual, reaching only 75% of typical rainfall compared to the 1981-2010 long-term average. June 2022 was drier, warmer and sunnier in the East but wetter, cooler and cloudier in the West. You can find our more on past weather in Ireland here.
Is this regularity down to any particular set of circumstances?
The hottest days occur in summer, when large areas of high pressure or anticyclones build up close to Ireland and they become slow-moving. In these situations, the jet stream may be forced to divert around the high pressure, often deflecting areas of low pressure to the north of Ireland leaving much of the country with dry and settled weather, often for days or even weeks at a time. In anticyclonic conditions, the air descends, which can reduce cloud formation and lead to clear blue skies, light winds and settled weather in summer.
From RTÉ Radio 1's The Business, what does sunshine do to our brains?
Our highest temperatures in Ireland usually occur when we are under the influence of tropical continental air, originating over North Africa and southern Europe. We are also likely to see sunny weather in Ireland with dry continental air coming from east to west, where as cloudy weather is more likely to be the result of a moist oceanic airflow from west to east
High temperatures and heatwaves are often front page news. A heatwave is an extended period of hot weather. In Ireland, a heatwave occurs when the daily maximum air temperature at a Met Éireann weather station is greater than 25 degrees Celsius for five or more consecutive days. Ireland occasionally experiences heatwaves but to a lesser frequency and intensity than those seen elsewhere around the world due to our more temperate climate being situated at the edge of the Atlantic Ocean. The longest heatwave in Ireland was for 14 days in August 1976.
As greenhouse gas concentrations continue to increase, research shows that extreme weather events such as heatwaves will increase in frequency and intensity over most land areas. For more information on understanding past Irish summers check out .
