Precipitation types the preceding adjective "freezing", becoming known as freezing rain or freezing drizzle. Frozen forms of precipitation include snow, ice needles, sleet, hail, and graupel. Their respective intensities are classified either by rate of fall, or by visibility restriction. Precipitation falls in many forms, or phases. They can be subdivided into: The parenthesized letters are the METAR codes for each phenomenon. Precipitation occurs when local air becomes saturated with water vapor, and can no longer maintain the level of water vapor in gaseous form. This occurs when less dense moist air cools, usually when an airmass rises through the atmosphere. However,
David Sleet David Sleet David A. Sleet is an American scientist recognized for championing the application of behavioral science to unintentional injury prevention and helping to establish injury prevention as a global public health concern. He has published hundreds of articles and book chapters and was co-editor of the Handbook of Injury and Violence Prevention.; Injury and Violence Prevention: Behavioral Science Theories; Derryberry’s Educating for Health; and the international prize-winning World Report on Road Traffic Injury Prevention. In 2016, Dr. Sleet retired from the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia where he served as the Associate Director for