Ask Marilyn
Sun Up, Temperature Down
Allen Bunn of Blytheville, Arkansas writes:
Marilyn: I am an early-to-bed and early-to-rise type. When I get up around 5 am, I look at the temperature. After dawn, I see that the temperature has usually dropped a degree or two. Why?!
Marilyn responds:
During a clear night with no change in the weather, air temperature drops hourly as the Earth loses heat. This loss continues beyond the time the Sun starts to rise because the planet needs to receive enough solar energy to slow, then stop, and finally reverse the flow of energy. The turnaround takes up to an hour or so.