Why Does Morning Dew Form on Grass?
What It Is
Morning dew is liquid water that appears on grass and other surfaces during the early morning hours.
How It Works
At night, the ground and plants lose heat. As grass cools, it can become colder than the surrounding air. When warm, moist air touches the cooler grass, water vapor condenses into droplets.
Why It Happens
Dew forms when specific overnight conditions are present:
- Clear skies that allow heat to escape
- Calm air that prevents mixing
- Moist air near the ground
Common Examples
- Wet grass early in the morning
- Dew on leaves or car roofs overnight
- Dew disappearing after sunrise
What to Know Next
As the sun rises, surfaces warm and the dew evaporates back into the air.
Simple Cautions
Dew is not rainfall. It forms from moisture already present in the air.
Closing Summary
Morning dew forms on grass when overnight cooling causes water vapor in the air to condense into liquid droplets on cool surfaces.
