Smoke from the cigarette has a higher temperature than the surrounding, giving it lower density, which makes it rise. As it rises, it cools down, which also decrease the net force on the smoke parcel.

Does cigarette smoke rise or fall outdoors?

Outdoor levels of tobacco smoke can be as high as indoors. If there is no wind, tobacco smoke will rise and fall and flood the local area with second-hand smoke; if there is a breeze, tobacco smoke will spread in many directions.

Does cigarette smoke float or sink?

Smoke will only rise as long as it is warmer than the surrounding air. At night a pocket of smoke will rise a bit, but as the air around it becomes warmer, it will actually sink back towards the ground and spread out horizontally.