I must have been reasonably awake, or I would not have received the impression that was creeping into me. It was not unlike one I had last winter, and I shivered, though the night was hot. The feeling grew until the atmosphere in the courtroom was exactly the same as a cold February morning, when the mockingbirds were still.

– Harper Lee

To Kill a Mockingbird, Chapter 21. If Jem is optimistic about Tom Robinson’s acquittal, his sister Scout is not. She describes the gloomy, pessimistic atmosphere in the courtroom as the verdict is awaited.