Maureen Flavin Sweeney, 98, received a special US House of Representatives honor for her part in World War II.
As a young woman at Blacksod lighthouse in 1944, she forecast an impending storm which changed the timing of the D-Day landings.
On the morning of June 3, 1944, the day she turned 21, Maureen dispatched a weather report from Blacksod Bay -- a bay of the Atlantic Ocean in Erris, North County Mayo, Ireland.
The barometer showed pressure was dropping rapidly, indicating a major Atlantic storm was due to arrive.
Later that morning she received a phone call from an English woman asking that she "please check… please repeat" the report. Examining the barometer again, Maureen confirmed that a storm would indeed hit the English Channel on June 5th.
Unbeknownst to her at the time this was the initial date chosen by Allied command for the invasion of Normandy, an operation that required clear skies for air support and calm water to ensure the safety of water-based landing craft.
Based on the reading, US General Dwight D Eisenhower postponed the D-Day landing by 24 hours.
The Sweeney family had been recording the weather every hour throughout the war.
They sent their observations to the Irish Met Service in Dublin, which were then forwarded without their knowledge to the headquarters of the Allied Expeditionary Force in England.
This hourly reporting continued until an automatic meteorological station was brought into operation in Belmullet in 1956. Only then, in 1956, did Maureen learn about the history-changing events that their reports had contributed to in 1944.
Recently she was presented with an award by the US House of Representatives for her role in the war.
"Her skill and professionalism were crucial in ensuring Allied victory, and her legacy will live on for generations to come," wrote Congressman Jack Bergman, who is the highest ranking veteran to serve in Congress.
Her son, Vincent Sweeney, said his mom was proud of her influence, but primarily "happy that she got it right".
While the death toll on D-Day was big, "it could have been a lot more" were it not for the report from Europe's most westerly weather station, he added.