Glossary

Automated Surface Observation System (ASOS)

Automated Surface Observing System (ASOS) units are automated sensors provide local weather information to an air charter operator before and during their flight. In the United States, there are more than 900 ASOS units at various airports and other locations. They report in hourly intervals, but may increase in frequency if meteorological conditions rapidly change. However, information can be accessed by the minute if needed.

Always Putting Safety First

As an air charter operator, a pilot will take every step to ensure each and every flight is as safe as possible. One of the steps taken to ensure this is accurately monitoring the weather. One of the most important features of an ASOS is to report the conditions on any given airport runway. Having access to the readily available weather information ensures a safe take-off and landing.

ASOS at Work

There is so much weather-related information out there that comes in handy to aircraft operators. They rely on an ASOS to provide accurate and timely information. Some of the information an ASOS unit will provide includes:

  • Sea-level pressures
  • The direction, speed, and character of the wind
  • Precipitation accumulation
  • Visibility
  • Conditions of the sky relating to cloud coverage
  • Ambient temperature and dew point temperature
  • Visual obstructions such as fog and haze
  • Basic weather conditions – the type and amount of snow, rain, and hail