As snowmelt (old German: Snesleiphi ) refers to the thawing snow to water when the ambient temperature, mostly due to the change of the season, increases. For snowmelt may occur even in winter when mild air is sucked in from the southwest to the front of a depression. A special case is the snow melt under Föhneinfluss when the air after crossing a mountain range is heated trockenadiabatisch. Since the relatively dry air can then record especially moisture, the effect of snowmelt is particularly large. Melting snow usually cause increased water level in streams, rivers and lakes, and often lead to floods, which make many people homeless and causing millions in damages.
Already by the Romans is known to use the point of melting snow, like for example a watershed " divergia aquae " to define natural boundaries. The definition of snowmelt can be seen more clearly from the Old German word Snesleiphi (snow loop). Mone describes this as the point from which the melting snow or falling snow slides down or grinds.