cold drop

Synoptic configuration equivalent to a dana. The expression is deeply rooted along the Spanish Mediterranean coast -particularly in the Valencian Community and the Region of Murcia- where most torrential rain episodes are referred to as such, regardless of whether a dana is present or not. It originates from the German word kaltlufttropfen (cold air pool/drop), which was coined in 1937 by meteorologist Richard T. A. Scherhag (1907-1970). He used that word to define a mid-latitude, cold-core depression isolated from the general westerlies, present only in the mid and upper levels of the troposphere, but not at the surface. In international meteorological terminology, it is known as a cut-off low. In Spain, meteorologist Manuel Ledesma (1916-2011) was the first to translate it as 'gota fría' around 1950, while fellow meteorologist Mariano Medina (1922-1994) helped popularize the term, defining it as 'a whirlwind [low-pressure system] of cold air, isolated within tropical air'. Its use began to spread widely in the 1980s following the catastrophic flooding caused by the collapse of the Tous Dam (Valencia) on October 20, 1982, as a result of an extraordinary torrential rain event. The improper use that began to be made of the expression led forecasters at the former National Institute of Meteorology to propose the use of the term DANA (acronym for isolated depression at high levels). Today, this latter term has achieved a certain level of penetration in society thanks to its dissemination in the media, but it has not managed to eradicate 'gota fría'. There are still many people who use this expression instead of dana, whose usage is dominant only within the meteorological community.