Does the sentence use modifiers correctly?

Waking at five o'clock, I found the sky pitch black and the usually frenetic city almost painfully quiet.

Yes, the sentence uses modifiers correctly. The modifier "Waking at five o'clock" describes the subject of the sentence, "I." The modifiers "pitch black" and "usually frenetic" describe the nouns "sky" and "city," respectively. The modifier "almost painfully quiet" describes the verb "quiet."