AWOS

Automated airport weather stations are automated sensor suites which are designed to serve aviation and meteorological observing needs for safe and efficient aviation operations, weather forecasting and climatology. Automated airport weather stations have become part of the backbone of weather observing in the United States and Canada and are becoming increasingly more prevalent worldwide due to their efficiency and cost-savings.

In the United States, there are several varieties of automated weather stations that have somewhat subtle but important differences. These include the Automated Weather Observing System (AWOS), the Automated Surface Observing System (ASOS), and the Automated Weather Sensor System (AWSS).

The Automated Weather Observing System (AWOS) units are mostly operated, maintained and controlled by the Federal Aviation Administration (FAA) in the United States, although there are AWOS units that are also operated by state or local governments and some private agencies. The American National Weather Service (NWS) and Department of Defense (DOD) play little to no role in the operation, maintenance or deployment of AWOS units. These systems are among the oldest automated weather stations in the United States, and many of them predate ASOS.

AWOS systems disseminate weather data in a variety of ways:

The following AWOS configurations are defined below in terms of what parameters they measure:

Also, custom configurations such as AWOS AV (AWOS A parameters plus visibility) are possible. Non-certified sensors may be attached to AWOS systems, but weather data derived from those sensors must be clearly identified as "advisory" in any voice messages and may not be included in any METAR observations.

As of January 31, 2015, the following manufacturers provide FAA-certified, non-Federal AWOS systems:

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