Abstract
Sierra Negra, one of the highest peaks in central Mexico, is the site of the Large Millimeter Telescope, a 50 m antenna that will operate between 1-3 mm. The site combines high altitude (4600 m) and extremely low atmospheric water content. We report the results of a comprehensive analysis of the weather data measured in situ from October 2000 to December 2006. The conditions at the site are benign given its altitude: the median value for the temperature is 1.1°C, for the wind velocity is 3.6 m/s, for the relative humidity during the dry season is 56% and for the atmospheric pressure is 590.1 mbar. We show that our measurements are consistent with a warm standard atmosphere model.
