Meteorological facts about peak Moussala:

Systematic meteorological observations are held from 1932 by the Meteorological institute of the Bulgarian Academy of Sciences (now National Institute for Meteorology and Hydrology).

Altitude of the peak	2925 m
Average annual temperature	- 3,1° C
Average monthly wind speed	10,5 – 4,9 m/s
Average annual wind speed	7,5 m/s
Average annual rainfalls	1000-1300 mm

AWS is functional from 01.12.2003 at BEO “Moussala. The system consists of:

-Sensor Collector QLI 50;

-Atmospheric pressure sensor PTB100B;

-Humidity and temperature sensor HMP45D;

-Ultrasonic Wind Sensor WS 425;

-Rain Gauge RG13H.

Accuracy:

Pressure:  ±0.5 hPa. Calibrated at 14.03.2007 (certificate).

Humidity: - ± 2%. Calibrated at 26.03.2007 (certificate).

Temperature: ±0.2 ºC. Calibrated at 26.03.2007(certificate) .

Wind Speed: ± 0.135 m/s or 3% of reading. Calibrated at 13.06.2006(certificate).

Wind Direction: ±2º. Calibrated at 24.06.2006 (certificate).

Rain Gauge: 0.2 mm for rain. For snowfalls and during wind gusts data are not relevant.