The Allied Commanders had had to postpone the invasion in the early hours of the 4th. It had proved to be a false start for some forces that had already departed for France. On the evening of the 4th the departure of the first wave of ships had got under way again, subject to a final review in the early hours of the 5th June.
Once again everything rested on what the weather was expected to be in 24 hours time. At the time they considered the weather forecast the rain was lashing the windows outside the conference room.
Admiral Sir Bertram Ramsay recorded the final decision in his diary:
Held a final meeting at 0415. This time the prophets came in smiling, conditions having shown a considerable improvement! It was, therefore, decided to let things be and proceed. The wind was still fresh and it is clear that Forces will have an uncomfortable initial journey, improving as the day proceeds.
Thus has been made the vital and crucial decision to stage and start this great enterprise which will, I hope, be the immediate means of bringing about the downfall of Germany’s ﬁghting power and Nazi oppression and an early cessation of hostilities.
I am under no delusions as to the risks involved in this most difficult of all operations and the critical period around H Hour when, if initial flights are held up, success will be in the balance.
We must trust in our invisible assets to tip the balance in our favour and to allow the landings to proceed without interruption. We shall require all the help that God can give us and I cannot believe that this will not be forthcoming.
As it happened the bad weather now convinced the senior German commanders in Normandy that an invasion could not possibly come in the next few days. Rommel took the opportunity to drive to Germany to see his wife and later Hitler. Others went on a table-top exercise away from the coast.
The German Atlantic weather ships had all been sunk or captured by the Allies, and with them their long range forecast abilities had been lost.