Uploaded June 2025 | Updated September 2026, 3 weeks ago

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We look at the most important weather map in history at the National Meteorological Library and Archive. More links below ↓↓↓

More pics for patrons: patreon.com/posts/extra-pics-from-130496628

Objectivity on Patreon: patreon.com/objectivity

Featuring Catherine Ross from the National Meteorological Library and Archive speaking with Brady.

The Met Office Library and Archive: metoffice.gov.uk/research/library-and-archive

More weather videos on Objectivity: youtube.com/playlist?list=PLd5y2WfrtsProO1DnNNe-psb82_C2ZiXV

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Films by James Hennessy and Brady Haran

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Some keywords: D-Day, weather, maps, Met Office, Catherine Ross, predictions, forecast, film footage, Normandy, France, WWII, moon, tides, Air Ministry, weather observations, isobars, wind, cloud circles, fronts, James Stagg, lead meteorologist, Eisenhower, Stagg diary, chief forecaster, ship observations, U-boats, German map, Enigma, Bletchly Park, home for lunch