An Automated Weather Observing System (AWOS) enhances aviation safety by providing real-time weather data to pilots, air traffic controllers, and airport operators. These systems play a crucial role in ensuring safe and efficient aviation operations. In this article we will look at AWOS, what is is, the benefits, and key differences from similar systems. This article focuses on Non-Fed AWOS in the United States.
What is AWOS?
An Automated Weather Observing System (AWOS) enhances aviation safety by providing real-time weather data to pilots, air traffic controllers, and airport operators.
What is AWOS?
Understanding Automated Weather Observing Systems
But what exactly is AWOS, and why is it so important?
An Automated Weather Observing System, or AWOS, is a collection of sensors and communication technology designed to monitor and report real-time weather conditions at airports and other aviation facilities. These systems operate 24/7, providing continuous updates on critical weather parameters such as:
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Temperature: Measures the current air temperature in degrees Celsius or Fahrenheit, a critical factor for engine performance, fuel calculations, and overall flight safety.
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Dew Point: Indicates the temperature at which air becomes saturated with moisture, crucial for understanding humidity levels and the potential for fog or icing conditions.
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Wind Speed and Direction: Captures the speed (in knots) and direction of the wind, which directly impacts takeoff, landing, and in-flight navigation.
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Visibility: Assesses the distance pilots can see along the runway and in the surrounding airspace, a key metric for safe operations, particularly during adverse weather.
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Cloud Cover and Ceilings: Reports the amount and altitude of cloud layers, helping pilots determine the best approach and departure paths.
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Altimeter Setting (Pressure): Provides the barometric pressure used to calibrate altimeters, ensuring accurate altitude readings critical for navigation and safety.
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Relative Humidity: Measures the amount of moisture in the air as a percentage, which affects passenger comfort and weather conditions.
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Precipitation: Detects the presence and intensity of rain, snow, or other forms of precipitation that could impact airport operations.
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Cloud Height: Monitors the vertical distance of clouds above ground level, aiding in safe navigation.
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Present Weather: Identifies current weather phenomena, such as fog, haze, or snow, providing critical situational awareness.
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Thunderstorm Detection: Alerts operators to thunderstorm activity near the airport, enhancing safety during severe weather.
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Freezing Rain: Detects freezing rain conditions that can pose significant risks to aircraft operations.
Why is AWOS Important?
AWOS enhances aviation safety and operational efficiency by offering pilots and airport operators reliable and accurate weather data. The information helps pilots make informed decisions about takeoffs, landings, and flight routes, especially under challenging weather conditions. Many commercial flight operations need Certified Weather for operations. For airports, AWOS ensures compliance with regulatory requirements and helps maintain uninterrupted service.
How Does AWOS Work?
AWOS units consist of multiple weather sensors strategically installed on or near the airport premises, see Order JO 6560.20C - Siting Criteria for Automated Weather Observing Systems (AWOS). These sensors collect data and transmit it via radio frequencies, telephone lines, or the internet to:
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Pilots using onboard communication systems
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Air traffic control towers
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Online aviation weather platforms
The data is processed and often broadcast in METAR format, a standard for aviation weather reporting worldwide.
Types of AWOS
In the US, only FAA-Certified AWOS can be used for official flight planning. International regulation can vary, ICAO compliance is the general standard. There are several classifications of AWOS, each offering different levels of capability:
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AWOS-A: Reports altimeter settings only.
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AWOS-I: Provides additional data on visibility.
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AWOS-II: Includes visibility and cloud ceiling.
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AWOS-III: Adds temperature, dew point, and wind information. (Minimum level to desiminate a METAR and transmit on the FAA's online network)
- AWOS-IIIP: Adds precipitation identification.
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AWOS-III PT: Enhances AWOS-III with precipitation and thunderstorm detection.
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AWOS-IV: Delivers the most comprehensive data, including runway surface conditions.
Benefits of AWOS
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Improved Safety: Real-time weather information reduces risks during takeoff, landing, and mid-flight.
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Operational Efficiency: Automation minimizes the need for manual weather observations.
- Pilot Prefernce: Attract General Aviation pilots.
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Cost-Effective: AWOS systems provide continuous data without requiring large personnel resources.
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Compliance: Ensures airports meet FAA and international aviation standards.
AWOS vs. ASOS: What’s the Difference?
While both AWOS and ASOS (Automated Surface Observing System) provide automated weather observations, there are key differences:
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Ownership: AWOS is typically owned and maintained by state, local, or private entities, whereas ASOS is federally operated.
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Data Frequency: AWOS can update more frequently (every minute, like Mesotech's AWOS Live platform), compared to ASOS (typically every hour).
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Capabilities: Reporting capabilities can be similar. ASOS can sometime feature more complex systems with multiple field stations.
Learn more about AWOS vs. ASOS vs. ATIS
Conclusion
AWOS systems are an indispensable tool in modern aviation, providing essential weather data that enhances safety, efficiency, and operational readiness. Whether you’re a pilot planning a flight or an airport operator ensuring compliance, understanding and utilizing AWOS is critical for success.
AWOS Live
Available for all of our systems, provides a secure live data stream from your AWOS to our cloud platform for viewing using a computer, tablet, or phone.
No app required —your users simply browse to your dedicated awos.live web address and up-to-the-second AWOS data will be at their fingertips.