Portend (verb)

1. To indicate or foreshadow in advance; to be an omen of; to serve as a warning of.
2. To indicate a future event or condition; to be a sign or warning of.

Origin:

Middle english portenden, from latin portendere, from por- + tendere to stretch — more at thin.

Examples:

1. The dark clouds portend a storm.
2. The market's performance this week portends a bearish trend.
3. His behavior portended trouble ahead.
4. The stars portend a prosperous future.
5. The portending signs of war were clear to those who cared to see them.