The power of prayers & The miracle at Dunkirk

During the 2nd world war several thousand allied soldiers, mostly British, were trapped by the Germans at a French coast called Dunkirk. All escape routes were sealed off. The sea escape route was impossible as the German submarines and war ships were heavily guarding it. The Germans were closing in from all other directions and a bloody massacre was expected the next day. No one was expected to live.
The British PM, Winston Churchill told the nation, “There is only one hope. Let’s all pray for them.”
Throughout that day and night the whole of Britain prayed for them. Special masses and prayers were conducted in every church.
That night, suddenly, there was a heavy and dense fog. It was totally the wrong season for fog and it never happened before. Under the cover of the heavy fog, the British ships crossed the French channel as the German subs and war ships could not detect them in the fog and rescued each and every one of the soldiers.
As soon as the ships returned home, the fog vanished. 
How and why the heavy fog formed and vanished is still one of the biggest meteorological mysteries.