In 1944, a young Irishwoman called Maureen Flavin drew up a weather report that helped change the course of World War Two.

Maureen was working at a post office on the far west coast of Ireland. Her duties included recording rainfall, wind speeds, temperature and air pressure.

On 3 June, she sent one of her hourly reports to Dublin, unaware that the figures were being passed on to the Allied headquarters in England.

It was the first indication of bad weather heading towards the coast of France, where hundreds of thousands of servicemen had gathered for the most ambitious operation of the war - the assault of the Normandy beaches on 5 June.

But after reading Maureen’s report, chief meteorologist Group Captain James Stagg advised a delay of 24 hours. D-Day was finally launched on 6 June, 1944. A date that went down in history.

Maureen's son Edward Sweeney spoke to Jane Wilkinson in 2024 about his mother’s role.

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(Photo: Omaha Beach, D-Day, 1944. Credit: US National Archives/AFP via Getty Images)

The weather report that changed the date of D-Day

Witness History

The weather report that changed the date of D-Day