Abstract
We present weather data acquired during the last four years with the meteorological station of the 1.5 m telescope at the Observatorio Astronómico Nacional at San Pedro Mártir. Measured temperatures are in the range of -15^o C to 20^o C. The relative humidity shows a seasonal dependence although with high variations in short scale times, specially during the summer nights. Measured pressure values are in the range of 550 to 565 mmHg. The median values for wind speed are 3.9 m/s during the day and 5.3 m/s during the night
