On average, the time of day when air temperature is the highest is usually about 3 PM, as heat continues to build up after noon. However, after 3 PM the Sun is low enough in the sky for more heat to be lost than absorbed, causing a gradual decline in air temperature.
When is air temperature the highest?
When do temperature inversions occur?
Temperature inversions occur when the normal heat gradient of the atmosphere—air is warmer near the ground and cooler in the sky—is reversed. A temperature inversion typically occurs in the late evening and disappears just after sunrise. A visual cue that a temperature inversion has happened is fog (or smog in an urban environment).