The weather was crucial to the success of D-Day. Actor David Haig has written a play called 'Pressure'.
The play, at the Minerva Theatre in Chichester, tells the true story of the tensions between General Eisenhower, the Allied Supreme Commander, and Dr James Stagg, the Chief Meteorological Officer for the Met Office.
When should the attack be launched? Simon has been to find out more.
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The latest weather for the west with Philippa
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Nick Thomas, an experienced endurance athlete, set off from Dover on Saturday morning.