The observatory in Trinity College recorded some of the county’s earliest weather records since it was built in the middle of the 19th century but the meticulous daily readings came to an abrupt halt the day the rising started on April 24, 1916 and didn’t resume until almost a month later on May 18.
In the RTÉ series Creedon’s Four Seasons In One Day, Met Éireann librarian Máiréad Traynor has revealed how a note from a student written into the record books in the spring of 1916 explains the gap in the painstaking records was due to the Republican uprising.
A note in the college’s 98-year-old weather records, signed by student S A Clark on April 24, 1916, simply reads: “Owing to the disturbances in Dublin the observations were not taken from the 24th to the end of the month.”
“In fact it lasted right up until the 18th of May,” said Ms Traynor.
“There is another note saying ‘owing to the rebellion in Dublin the observations were not taken in Dublin during this time’, again signed S A Clark.”
Ms Traynor told the documentary that S A Clark — the student tasked with taking the weather readings — could have been busy protecting the college from the Republicans.
“The rebels tried to take Trinity College but it was defended by the students and the graduates and by soldiers who came down from Dublin Castle,” said Ms Traynor.
“So the report the week after the rebellion — they called it the Sinn Féin rebellion in the Irish Times — said Trinity College remained true to its traditions, so it was a bastion for the empire.
“I often wonder if Clark had any role in defending the college. He was a student at the time. He would have been taking the [weather forecast] as part of his studies.”
The Met Éireann librarian reveals that the earliest records in Met Éireann date back to 1855 and contain more than just the weather, even noting the type of illnesses prevalent in the area.
Meanwhile, the documentary also revealed how a Mayo lighthouse changed the course of the Second World War.
A weather forecast predicting an incoming Atlantic storm from the Blacksod station — the most westerly point in Co Mayo — saved the D-Day invasion from potential disaster.
When Irish Coast Guardsman and lighthouse keeper Ted Sweeney passed on the weather report of a falling barometer which forecast a major storm, D-Day was postponed by the Allies for a day. His son, Jerry Sweeney, who is the current lighthouse keeper, said his parents changed the course of history by forecasting stormy seas.
He said: “On June 3rd, my parents were taking the weather as usual in Blacksod. They forwarded the weather to Dublin and it went from Dublin to England. But on that day they received two phone calls back from England, it was a woman on the phone and my mother answered both calls. The woman asked my mother [Maureen] to please recheck the report.
“The first time she rang and then an hour afterwards she got a second phone call asking to check again. The exact weather forecast was ‘the glass was falling in the [barometer] and the sea was rising’. It was bad storm weather coming in from the Atlantic.”
“Based on the weather forecast from Blacksod they decided to postpone the D-day landings by 24 hours. My father found out long after the war.”