00:00This lake looks like it's boiling, but the cause is cold air above it.
00:04You're watching steam fog, a familiar fall site.
00:07Here's how it happens.
00:08Lakes and ponds retain heat from the summer and early fall, while the air turns sharply
00:14colder, especially overnight.
00:15On chilly nights, water evaporates from the relatively warm lake, adding invisible water
00:20vapor to the air.
00:21As the humid air rises away from the warm lakes, it cools and water vapor condenses
00:26into tiny droplets, which we see as fog.
00:28Those ghostly wisps are a cloud forming right above the water.
00:32Add the golden light of sunrise, and everyday science becomes something spectacular.
00:37So after the next chilly night, look toward your nearest lake or pond.
00:40You might catch fall putting on its own smoke show.
