REVISITING THE EXTREME COLD AIR OUTBREAK OF JUNE 1967 OVER CENTRAL ARGENTINA, FIFTY YEARS LATER
Ramiro I. Saurral y Juan J. Ruiz
Departamento Centro de Ciencias de la Atmósfera y los Océanos, FCEyN, UBA
Centro de Investigaciones del Mar y la Atmósfera (CONICET-UBA) y UMI-IFAECI/CNRS
Manuscript received on 7th January 2018, in its final form on 29th May 2018
During the month of June 1967 cold polar air moved from the Antarctic continent into central Argentina, where it brought extremely low minimum temperatures, snow and extensive damage to crops. Fifty years later, this paper revisits such synoptic situation making use of reanalysis data as well as numerical modelling in order to characterize the physical mechanisms at play. In a statistical context, this cold air outbreak was the most intense in the last 50 years in an extensive area covering central Argentina, not only at the surface but also at low and middle levels of the troposphere. The cold air outbreak was associated with the displacement of a cold front, behind which a polar air mass moved from subpolar latitudes onto central and northern Argentina. Although the air mass suffered a noticeable modification while traversing oceanic areas, as seen by the numerical simulations, temperature advection first and radiative cooling afterwards contributed to the extreme minimum temperatures.