You probably noticed some nights seem to cool off much quicker than some, especially those calm, clear nights. We can thank radiational cooling for that!
As high pressure sits overhead and the winds calm down along with low dew points, radiation from the earth’s surface is allowed to escape into our atmosphere. As radiation leaves the surface, a cooling effect occurs and the temperature drops.
At night, cloud cover can stop this process because the water vapor within the clouds can reabsorb this radiation and reemit it towards the ground. This will keep temperatures from falling as fast because the radiation can’t leave the surface as quickly.
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