Group Captain James Martin Stagg, CB, OBE, FRSE (30 June 1900 – 23 June 1975) was a British Royal Air Force meteorologist who notably persuaded General Dwight D. Eisenhower to change the date of the Allied invasion of Europe in World War II, from the 5th of June to the 6th of June 1944. He was born in Dalkeith Scotland and graduated from Edinburgh University firstly becoming a science master at a school in Edinburgh. He later joined the British Meteorological Office and in 1943 he was commissioned a Group Captain in the RAF and appointed as the chief meterological officer for Operation Overlord. He remained at the Met Office until 1960 and lived in Carlton Road Seaford until his death in 1975 aged 74.
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