A strange day in July

It was a cold day in July and Lily and John are by the bay watching the tide come in.
Suddenly a dark spot appears in the water."Lily come here i see something in the water come quick " yelled John.

Lily came over to were John was and she said "there is nothing there".
"There is i saw something there i did i swear".
"It must be a figure of your imagination".
"No it isn't."

So they went home and ate dinner and went to bed. That night John opened the window and climed out and went to the bay and saw nothing. The next day at the bay he saw nothing again so he decided that there was nothing there.