Dew happens when the temperature drops in the night lower than the air is able to hold water. The warmer it is the more water the air can hold. As the temperature drops in the night the water content will stay the same but the air loses its ability to hold that much water. The result is dew.
In the morning the sun will come out and the dew will evaporate back into the air.
Sheep sometimes will get enough water from eating grass that has an abundance of dew. Dew can be a type of gift from God that is accessed in the morning before the hustle and bustle of life makes it harder to hear from God. As we sit in God's presence reading the Bible we gain insight from the Holy Spirit who teaches us the Bible.
Deut 32:2 "Let my teaching drop as the rain, My speech distill as the dew, As the droplets on the fresh grass And as the showers on the herb."
Psalm 5:3 "In the morning, O LORD, You will hear my voice; In the morning I will order my prayer to You and eagerly watch."