Spring 2026 - General Discussion

Still hasn't fallen below 10C in Dublin since the 18th May. Even May 2024 wasn't as persistent with this and had the odd night dip below 10C to break up a period. I don't recall a period as persistently mild at night as this in May before here.

7 20C days in May for Dublin Airport is exceptional @compsys. You have to go back all the way to 1952 to find anything close to that and it's only 6 such days. Recently 2020 and 2018 had 5.

Not quite, there was 18 days that achieved 30C from 1986 to 2006 though 10 of those were from 1995 alone!

2006 to 2026 has had 28 such days.

Bear in mind, this is NOT a homogenised dataset so whilst it may be indicative of the trend, it cannot be used to show trend in of itself as the station availability in some modern years will be skewing it.

Though I'm sure many already know here, I thought I'd share this post I did on IWO this morning surrounding the idea of Leaving Cert weather.

The "Leaving Cert Weather" phenomenon is often a throw around term in Ireland to describe a period of fine weather coinciding with the Leaving Certificate exams and then a change happens once the exam period passes.

Is there some truth to this? Well yes there actually is to an extent but there's more nuance than what initially meets the eye. I will try and explain this as simple as I can. During the months of April and May, the stratospheric polar vortex (a ribbon of air surrounding the arctic circle in the stratospheric level of the atmosphere), which keeps Irish winters relatively mild and sometimes stormy due to enhanced westerly winds off the North Atlantic, dies down and increases the risk of easterly winds. Easterly winds often give our best weather in Ireland in terms of warmth and sunshine though the east coast can be an exception due to being exposed so significantly cooler here. May is the sunniest month of the year on average in Ireland due to this phenomenon so even though June and July have a higher theoretical maximum sunshine, this is rarely fulfilled here.

This phenomenon can last into early June due to the same physics but later in June as pressure rises over the ocean and falls over the continent due to increasing heat and instability, we can get what's called a return of the westerlies or European Monsoon where the westerly winds return bringing cloudy, humid air in off the North Atlantic. This especially becomes apparent through July and August. So whilst say Spain gets hotter and sunnier, Ireland gets cloudier and more humid.

With the scientific explanation out of the way, is the Leaving Cert period actually that reliable for fine weather and how has it fared in recent years? Are any of these how you remember? It's actually more variable than you think.