Why do you see your breath outside on a cold day? ?

Chilly, festive-feeling air has returned to South Central Texas!

When temperatures turn cold, sometimes you can see your breath when holding a conversation or simply just breathing outside.

So what exactly causes your breath to turn into a mini-cloud when you exhale? We dove into the science below:

The science

This process relies on just the right balance between the air temperature and the dew point temperature.

The human body contains nearly 70% water, so the air in our lungs largely consists of water vapor.

When you exhale a warm breath, the cold air outside quickly lowers the temperature of that breath, sometimes allowing it to reach the dew point.

Similar to how a cloud and fog forms, when the air temperature reaches the dewpoint temperature, that water vapor then condenses.

That process creates the small, brief cloud that we see when breathing outside in cold conditions.

So next time you are outside playing with the kiddos and see your breath, you’ll know the science behind why that happens!

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