Commentaries:
"Morning" is the Hebrew boqer which Strong, Gesenius, and the Theological Wordbook of the Old Testament all more precisely define as "daybreak," "dawn," or "the breaking forth of light." The Old Testament writers also use it to mean "early" or "promptly," but is more frequently used to indicate the light part of the day as opposed to the dark. It is highly likely that God intends it to mean "daybreak."
John W. Ritenbaugh
God's Promises Are Sure!
This verse shows Pharaoh dreamed at night, and verse 14 records that Joseph was released from prison in the morning. This interesting contrast implies that while Joseph was in prison, he was in darkness. Metaphorically, the biblical writers use darkness to describe being ignorant of the right way, living in unbelief, and being dangerously subject to wandering, falling, injury, pain, and even death. Proverbs 4:19 says, "The way of the wicked is like darkness; they do not know what makes them stumble."
John W. Ritenbaugh
God's Promises Are Sure!