Freezing fog is a super cool weather phenomena that happens in the cool winter months! We were lucky enough to see some just the other day.

Fog occurs when cold air settles in over relatively warm, moist ground. It’s basically a cloud on the ground. Freezing fog is happens when the air becomes saturated with water vapor that is supercooled.

Supercooled water is between 32 degrees and 5 degrees Fahrenheit. The water is cold enough to freeze, but since it is not in contact with anything solid, ice crystals don’t form.

The water vapor in freezing fog is so cold that when the droplets touch something, like a spider web, leaf, of tree bark, it instantly freezes.

Fun Fact – Freezing differs from ice fog, which is extremely rare and only occurs at temperatures well below freezing. The water vapor in ice fog is actually tiny ice crystals suspending close to the ground.

Teaching Science at Home

Want to learn more about fog? Check out the following articles:

• What is freezing fog?
• What is the difference between ice fog and freezing fog?
• Freezing Fog {Video}

Related Homeschool Science Activities

Keep the learning going with these science activities!

• Homemade Fog – Make your own fog at home, all you need is a glass jar, hot water, rubbing alcohol, plastic wrap, rubber band, and ice. Fill the jar a third of the way with the hot water. (Caution- The jar will get very hot; be sure to use the necessary precautions.)
• Instant Ice – Make your own instant ice from super-cooled water.