Weather in History 1900 to 1949 AD Weather in History 1900 AD to 1949 AD 1940 (May & June): FINE WEATHER: FALL OF FRANCE/DUNKIRK EVACUATION WARM & SUNNY. Allowed air operations on both sides [ i.e. RAF & Luftwaffe ] to proceed unhindered during the 'Fall of France', Dunkirk [ Operation 'Dynamo' ] etc. The last week of May, and the first week of June, 1940, the weather in the eastern Channel was unusually quiet, which allowed the 'little' ships to operate where they were not designed to do so. Even Force 5 or 6 winds would have significantly changed the course of history, as many fewer than the ~364 000 troops of all nationalities (mainly British & French, but also Poles and Belgians) would have been recovered to the English side of the Channel: ended 4th June, but the principal period of evacuation was 27th May to 1st June. The weather wasn't the primary factor - it allowed, for example, the Luftwaffe to attack formations trying to embark to cross the Channel; the main reason the troops were evacuated in such large numbers was that German High Command failed to press home the advantage for whatever reason. (Ref: 14)
