On which floor do weather phenomena such as clouds, rain, fog and snow occur?

Weather phenomena such as clouds, rain, fog and snow occur in the troposphere.

Meteorological problems related to human life basically occur in the troposphere. It extends upward from the sea level by about 17 km, but it contains 75% of the air on the earth. It is the area where convection (hot air rises and cold air falls) is the most vigorous, and it is also the place where weather phenomena occur. About 80% of the water vapor in the atmosphere exists in the troposphere, and the closer to the ground, the higher the water vapor content. The efficiency of absorbing sunlight in the atmosphere is not high. About 50% of sunlight is absorbed through the ground and released into the air.

The plane flies in the stratosphere to avoid being affected by the weather.