ATIS and AWOS Broadcasts: How to Obtain and Use

Before you ever key the mic at a towered airport, you are expected to have already done your homework — and that homework begins with the Automatic Terminal Information Service, or ATIS. At non-towered airports equipped with weather sensors, the Automated Weather Observing System (AWOS) or its cousin the Automated Surface Observing System (ASOS) fills the same role. These broadcasts exist so that every pilot arriving or departing has a consistent, up-to-date snapshot of the weather and airport conditions without tying up the control frequency. Understanding how to find, decode, and use these recordings is not just a test requirement — it is a foundational cockpit habit that keeps communications crisp and situational awareness sharp.

This article walks you through what ATIS and AWOS actually contain, how to obtain them, what each element means, and the practical habits and regulatory context that show up on the FAA Private Pilot knowledge test.

What ATIS Is and How It Works

ATIS stands for Automatic Terminal Information Service. It is a continuous, pre-recorded broadcast of non-control information for busy, typically towered airports. The recording is updated whenever there is a significant change in conditions — typically when the weather observation changes, when a new hourly observation is issued, or when an important NOTAM (such as a runway closure or instrument approach in use) needs to be announced. Each update is assigned a successive letter of the phonetic alphabet — Alpha, Bravo, Charlie, and so on — called the information identifier. When the recording cycles through Zulu, the next update returns to Alpha.

ATIS is broadcast on a dedicated VHF frequency listed in the Airport/Facility Directory (now called the Chart Supplement) and on instrument approach charts. This means you can tune it on a second radio while on another frequency, or listen before you even start the engine. Many airports also broadcast ATIS on certain VOR frequencies and, at some locations, on a phone line or through digital ATIS (D-ATIS) accessible via the internet or a datalink receiver in the cockpit.

What ATIS Contains

A typical ATIS recording follows a standardized format. While the exact wording varies slightly by facility, the FAA Aeronautical Information Manual (AIM) describes the standard elements, which typically appear in this order:

• Airport name — identifies which airport's information you are hearing.
• Information identifier — the phonetic letter (e.g., "Information Delta") so you can confirm you have the current recording.
• Time of observation — given in Zulu (UTC) time.
• Wind — direction in degrees magnetic and speed in knots; gusts are included when applicable.
• Visibility — in statute miles (or fractions thereof).
• Sky condition — cloud layers described by coverage (few, scattered, broken, overcast) and height in feet AGL.
• Temperature and dewpoint — in degrees Celsius.
• Altimeter setting — in inches of mercury (e.g., "Altimeter 29.92") — one of the most critical elements for safe flight.
• NOTAMs and special notices — runway closures, taxiway construction, braking action reports, special procedures in effect, bird activity, and similar safety-relevant items.
• Instrument approach in use — at IFR-capable airports, the approach type and runway are announced.
• Active runways — the runways in use for arrivals and departures.
• The recording ends with an instruction to acknowledge receipt on initial contact with the controller, e.g., "Advise on initial contact you have Information Delta."

The altimeter setting deserves special emphasis. The FAA requires pilots operating at or below 18,000 feet MSL to use the current altimeter setting of a station within 100 nautical miles of the aircraft. Without the correct setting, your altimeter will display an incorrect altitude — a potentially dangerous error near terrain or during an approach.

AWOS and ASOS: Automated Weather at Smaller Airports

AWOS (Automated Weather Observing System) and ASOS (Automated Surface Observing System) serve a similar purpose to ATIS but are found at airports — often non-towered — where a full-time human observer or dedicated ATIS broadcast is not available. Both use sensor arrays to continuously measure and report weather conditions. ASOS is the FAA/National Weather Service standard system; AWOS is an FAA system that comes in several tiers:

• AWOS-1 — reports altimeter, wind, temperature, and dewpoint.
• AWOS-2 — adds visibility to the AWOS-1 package.
• AWOS-3 — adds cloud/ceiling data, providing what most pilots think of as a full weather report.
• AWOS-3P and AWOS-3PT — add precipitation identification and/or lightning detection sensors.

You can receive AWOS/ASOS in three ways: by VHF radio (the frequency is published in the Chart Supplement and on sectional charts), by telephone (a dedicated number listed in the Chart Supplement), and sometimes via digital datalink. At non-towered airports, tuning the AWOS frequency a few minutes before reaching the traffic pattern gives you current winds, altimeter, and visibility — critical inputs for choosing the correct runway and making safe pattern decisions.

Unlike ATIS, AWOS and ASOS broadcasts are largely automated and computer-generated. They do not include runway-in-use information or controller-generated NOTAMs — those decisions remain with the pilot at non-towered fields. Always cross-check AWOS data with your own visual observations and pilot reports (PIREPs) when conditions are rapidly changing, because sensor-based systems can momentarily lag behind developing weather.

How to Use ATIS and AWOS in the Cockpit

The practical workflow is straightforward. When departing a towered airport, obtain ATIS before calling ground control. Write down or mentally note the information identifier, active runway, wind, visibility, altimeter, and any NOTAMs. When you call ground, your opening transmission includes the phrase "with Information [letter]" — for example, "Cessna 172, Tango Sierra Romeo, at the FBO, VFR to Springfield, with Information Delta." This tells the controller immediately that you are current and briefed, saving everyone time.

For arrivals, obtain ATIS while still en route — typically 20 to 30 miles out, or when the airport appears in your radio range. This gives you time to set the altimeter, mentally prepare for the active runway, and note any special procedures before you need to contact approach control or the tower. The AIM specifically notes that pilots should obtain the latest ATIS broadcast before contacting approach control.

At non-towered airports with AWOS, tune the frequency early in your approach. Use the winds to select the runway, set your altimeter from the reported setting, and note the visibility to ensure you can fly VFR legally and safely into the pattern.

Key Numbers and Rules

• ATIS information identifiers cycle Alpha through Zulu and restart at Alpha after Zulu.
• ATIS is updated with each new hourly weather observation or whenever a significant change in conditions occurs (such as a ceiling dropping below 1,500 feet or visibility below 3 miles).
• Pilots must use the altimeter setting from a station within 100 NM of the aircraft when flying at or below 18,000 feet MSL (14 CFR Part 91).
• ATIS frequencies are listed in the Chart Supplement (A/FD) and on instrument approach charts.
• AWOS and ASOS frequencies and telephone numbers are published in the Chart Supplement and depicted on sectional aeronautical charts.
• AWOS-3 is the minimum tier that reports cloud coverage and ceiling — the tier needed for a complete weather picture.
• Acknowledging ATIS on initial contact is expected by ATC; failing to do so will typically prompt the controller to ask if you have the current information.

Common Test Traps

• Confusing ATIS with clearance delivery. ATIS is a recorded broadcast — it carries no ATC instructions or clearances. You listen passively; you do not talk back to it. Clearances come from clearance delivery or ground control.
• Thinking ATIS is only for IFR pilots. Every pilot operating at a towered airport is expected to have the current ATIS before contacting ATC, regardless of flight rules. The FAA knowledge test may test whether VFR pilots are obligated to monitor ATIS.
• Mixing up AWOS tiers. Test questions sometimes ask what a specific AWOS tier reports. Remember: AWOS-1 has no visibility, AWOS-2 adds visibility, and AWOS-3 adds ceiling — the full picture.
• Forgetting to update the altimeter from ATIS/AWOS. The recorded altimeter setting is perishable — conditions change. Use the most recent setting available and update it as directed by ATC or as new broadcasts become available during flight.
• Assuming AWOS replaces local knowledge. Automated systems can fail to detect localized phenomena such as fog patches, wind shear, or rapidly building thunderstorms. Always treat AWOS as one input among several, and request PIREPs or check METARs and TAFs for a fuller picture.

Mastering ATIS and AWOS is one of the quickest ways to sound like a competent, professional pilot on the radio. More importantly, it builds the habit of always knowing your weather environment before you fly — a habit that pays dividends at every level of aviation.