– Why does playground equipment get wet sometimes in the mornings when it hasn’t rained?



Simple question but was having trouble finding the information + sources googling in Australia.

But when visiting local playgrounds sometimes the equipment is wet in the morning even when it hasn’t rained or when the playground has a shade sail over it. Why is that?


In: Earth Science

It’s condensation. The equipment cools over night, and usually the coldest part of day is just before sunrise. As the air temperature rises and the playground equipment lags behind to warm up the moisture in the air accumulates on its surface.

The night sky is really really cold. Things exposed to the sky radiate heat, cooling themselves down. When their temperature drops low enough, warmer air that comes in contact with them cools, loses some of its ability to carry water vapor, and the excess water is deposited on the cold things.

The wetness is called dew, the temperature at which dew deposits is called the dew point.