The summer night air was feverish. The whisper of the breeze curled within my ear. The crowd's roar was thunder. Question How does the author use metaphors in the sentences

The writer uses metaphors in the sentences to exaggerate as it shows how loud the crowd was at night as they refer the noise of the crowd like thunder. Thuder is extremly loud. the writer describes the night air as feverish which tells the reader that it was a very cold night and someone could get a fever.