Why does it stay warm when the sun is behind a cloud?

Answer

Dear Hannelore

When it is very hot, it is nice if a cloud appears in front of the sun. It then feels noticeably cooler because the direct sunlight no longer hits the body. However, the ambient temperature does not change significantly at that time and so it can still remain very warm. Only when the sun has disappeared for a longer period of time, behind the clouds or behind the horizon, does the air lose more heat than it receives from the sun and the ambient temperature will also decrease significantly until the sun comes out again.