Why it’s always colder during clear nights

Why it’s always colder during clear nights
Temperatures are usually cooler when the sky is clear at night (Source: KSLA News 12)

(KSLA) - Temperatures of course range a lot over the course of 24 hours, but the clouds can play a major role in the temperatures during the overnight hours.

Clouds can keep the temperature slightly warmer at night
Clouds can keep the temperature slightly warmer at night (Source: KSLA News 12)

As we all know, the sun will heat the Earth’s surface during the day. Then at night, the sun is on the other side of the globe, so temperatures cool back down. The clouds can be a difference maker, day or night.

On nights with cloudy conditions, the sun will set and the temperature will begin to cool like normal. However, the clouds will serve as a “blanket” to keep the temperature a little warmer. The clouds can actually re-emit some heat back towards Earth’s surface.

Temperatures are usually cooler when the sky is clear at night
Temperatures are usually cooler when the sky is clear at night (Source: KSLA News 12)

On the other hand, during nights with clear conditions, the heat will escape back out to space with nothing to stop it. Therefore it will continue to cool down with no incoming heat! This can also lead to frost during cold winter nights! You can read about that here.

Just like the clouds affecting temperature at night, the wind also can. If there is a breeze at all, that can slow the cooling process down overnight. If the winds are calm, then the temperatures can fall quicker. Wind direction also plays a part too. If it is blowing out of the south, that can make it much warmer overnight. If the wind is from the north, then the temperature can be cold, but not as cold as if it was a calm wind.

When you combine the clear conditions with calm wind, that is usually when the temperature will cool down at its fastest rate during the evening and overnight.

You can always catch the latest forecast on air, online, and on our KSLA First Alert Weather App:

Copyright 2020 KSLA. All rights reserved.