Maureen Sweeney (1923-2023)

An Irish woman whose weather observations at Blacksod Point, Co. Mayo in 1944 changed the timings of the D-Day landings, Maureen Sweeney, has died aged 100 on 17th December 2023.

Maureen (née Flavin) was working in Blacksod post office at the time and took that vital hourly reading on her 21st birthday, 3rd June 1944. The readings at the weather station at the lighthouse showed a steady wind and increasing rain as the pressure continued to drop. This indicated unsettled, stormy weather that would affect the English Channel on 5th June, the planned date for the D-Day landings known as Operation Overlord. When the reports reached England, officials rang the post office at Blacksod to confirm the readings directly. Maureen did not learn of the importance of her readings until 1956. During an interview with RTÉ, Maureen noted that the US Army “could arrange everything, but they couldn’t pre-arrange the weather.”

The area of low pressure, identified by Sweeney, resulted in strong southwesterly winds in the English Channel. This would have made the seas too rough for the landing of troops, with too much cloud for bombing operations to be successful. A temporary ridge of high pressure that followed on 6th June offered the perfect window for the landings. German weather forecasters were far more limited in the information available to them, as they had limited vessels in the Atlantic and their weather stations in Greenland had been shut down. Although early June was identified as a possible date for invasion by German military planners, the expected continuation of the disturbed pattern of weather was considered to make a landing impossible. They stood down some of their troops on defensive duties, leaving the coast without numerous senior officers.

An observation sheet completed by Maureen on 3rd June 1944

An observation sheet completed by Maureen on 3rd June 1944

Maureen was honoured by the United States government in 2021 with a medal, acknowledging how her observations led to the delaying of the critical landings by 24 hours, thus ensuring their success and saving the lives of countless US soldiers during the operation. A proclamation of her achievements was placed in the US Library of Congress.

A native of Co. Kerry, Maureen moved to Co. Mayo where she took up the job in Blacksod post office. She later married the son of the post mistress, Ted Sweeney, who had confirmed her readings that day in 1944. She ran the post office until she retired in the 2000s. She passed away at a nursing home in Belmullet, Co. Mayo on 17th December 2023.

Met Éireann would like to offer our sincerest condolences to Maureen’s family, and to celebrate the legacy of Maureen for her part in this pivotal moment in Irish and International weather history.

Further reading: Met Éireann’s Exceptional weather event report – Forecasting D-Day landings 

Omaha Beach, June 6, 1944 by Robert F. Sargent, National Archives and Records Administration, Public domain, via Wikimedia Commons

Omaha Beach, June 6, 1944 by Robert F. Sargent, National Archives and Records Administration, Public domain, via Wikimedia Commons