The storm of January 1, 2000, north of the city of Mendoza

Abstract

The objective of this paper is the study of the conditions observed before and during the development of the convective storm recorded the last hours of January 1, 2000, that affected an area located north of the city of Mendoza, including the International Airport. The work also attempts to determine the behavior of the dynamic and thermodynamic variables that triggered off this case of severe convection. The hourly surface data and daily radiosoundings of Meteorological Station Mendoza Aero, identified as SAME, were analyzed for the period December 30, 1999 to January 2, 2000. The synoptic scale analysis was done with information of National Center for Enviromental Prediction and National Center for Atmospheric Research (NCEP/NCAR), USA, and the results from Centro de Previsao de Tempo e Estudos Climaticos (CPTEC), Brazil. Mesoscale precipitation information was obtained from Instituto Nacional del Agua (INA) network, Argentina. During one hour of the storm the record in SAME was 66.1 mm, surpassing the historical daily and hourly maximum. Principal results shows that there was an intense advection of warm and humid air on the surface, proceeding from the northeast of the country, while a short wave trough axis came from the Pacific Ocean. Nevertheless wind hodograph showed similar characteristics like a weak isolated storm, the intensity was enhancement by a dynamic trigger represented by the trough. Even though the phenomenon did not differ from the usual storms with respect to the time of occurrence and duration, it had extraordinary features in regards to the precipitation intensity, that surpassed the historical daily values at the SAME. It is necessary to improve research about physical mechanisms of the storms and its climatology for better indentification and predictions, and also to understand the mechanisms that led to the production of intense precipitation.