How meteorological variables recorded at 4000m can provide useful information for inhabitants affected by mountain weather in the Argentinean subtropical Andean region

During 2004 at the Subtropical Andes (26° 52' 35”S – 68° 18' 37”W, 4000 m) an automatic weather station was installed. From April to December, meteorological conditions on the mountain were observed in order to better understand the atmospherics signals in high levels. The weather station was surrounded by several mountains between 4000 an 5000 m and situated next to the a gendarmerie post where an small quantity of people lives and works and close to the San Francisco pass in the border between Argentina and Chile. This pass (4747 m) can be reached by the paved national road number 60. The region belongs to the province of Catamarca; an small or middle size town with lodging facilities and thermal waters is not far from the area. Since 1950, a climatological station from the Servicio Meteorológico Nacional is located 230 km to the southeast, at the city of Tinogasta (28° 04'S – 67° 34'W, 1201 m). Data from both stations are useful for those whose lives are affected by mountain weather in either recreational or residential settings.

Several notions on mountain weather are examined over both stations. Observed indicators of atmospheric conditions, such as temperatures, daily extreme temperatures, winds, temperature, and humidity from both weather stations were described, compared and analyzed. Weather phenomena such as the Foehn effect over the Andes (Zonda Wind) were recorded during that period. Conclusions about the local circulation are reached using the information recorded, which benefits those who use Route 60 as a means of crossing countries, as well as for those living in the region.