The second line on this page contains the start of a sentence with "First, black boiling clouds..." But there is no "Second,..." or "Next...."
Usually when you start a sentence with "First", you intend to start another sentence in succession, i.e., "Next" or "Second" or "Then". "First", this happens. "Then", that happens. etc.
If you read this section out loud it really sounds awkward.

I can find 'em, but I don't know what they mean. Other than grammar is not MS's strong point.