Portents marking significant historical events. In Scripture the phrase refers principally to signs indicating the coming of the Messiah and the kingdom of God (both in the ministry of Jesus Christ and at the end of time).
Signs of the times signifying the future deliverance of Judah
2 Kings 19:29-31 pp
Isaiah 37:30-32The fruitfulness of the earth is to be a sign to Hezekiah that there will be a fruitful remnant of Judah.