Pilot Reports - the underused superpower in your weather briefing

Pilot reports (PIREPs) are real-time weather observations filed by pilots in flight, and they are the single most underused tool in the aviation weather system. Forecasts are models and METARs are surface point measurements at airports, but only a pilot flying through the actual sky between airports can report what the weather is truly doing there. Filing one takes about two minutes of radio time and can directly shape a safer flight for the pilot behind you.

What Is a Pilot Report?

A PIREP is a human pilot telling air traffic controllers, flight service, and the broader aviation community what the weather is actually doing at a specific location, altitude, and time. It is not a forecast and not a surface measurement. It is eyewitness testimony from cruise altitude.

There are two types:

• UA — a standard, routine pilot report. Most reports you file will be UA.
• UUA — an urgent pilot report. Reserved for tornadoes, severe or extreme turbulence, severe icing, hail, low-level wind shear within 2,000 feet of the surface, or volcanic ash. Flight service prioritizes UUAs and distributes them quickly.

Most filings are routine: cloud bases sitting lower than forecast, light chop at a given altitude, visibility reduced in haze. Nothing dramatic — just truth.

Why PIREPs Matter More Than You Think

Forecasts degrade the farther they reach into the future. A 6-hour TAF is reasonably solid. A 12-hour TAF is decent. A 24-hour TAF is an educated guess wrapped in conditional probability. Once a forecast period enters your actual flight window, the most accurate weather data available is whatever the pilot a few miles ahead of you just reported.

The ACS (Airman Certification Standards) explicitly expects pilots to know how to obtain and interpret PIREPs during weather information tasks. The instrument ACS is even more pointed, because instrument flying without real-world weather data is significantly harder.

How Do I Read a PIREP?

Raw PIREPs look like a license plate from another planet. Here is a real example, decoded line by line:

KMRY UA /OV MRY180030 /TM 1432 /FL055 /TP C172 /SK BKN045-OVC070 /TA 05 /WV 21020 /TB LGT /RM SMOOTH ABOVE CLOUDS

• KMRY UA — Routine pilot report filed near Monterey, California
• /OV MRY180030 — Over the Monterey VOR, 180-degree radial, 30 nautical miles out (south-southwest)
• /TM 1432 — Time: 14:32 Zulu
• /FL055 — Altitude: 5,500 feet
• /TP C172 — Aircraft type: Cessna 172
• /SK BKN045-OVC070 — Sky: broken at 4,500, overcast at 7,000
• /TA 05 — Temperature aloft: +5°C
• /WV 21020 — Wind: 210° at 20 knots
• /TB LGT — Turbulence: light
• /RM SMOOTH ABOVE CLOUDS — Remarks: smooth on top

That single report describes the actual cloud layers, temperature, wind, ride quality, and the useful fact that it smooths out above the deck — far more than any model output can capture.

Where Do I Find Pilot Reports?

Four reliable sources:

1. ForeFlight — Enable the PIREP map layer and tap any symbol for the decoded text.
2. Aviation Weather Center — At aviationweather.gov, pull PIREPs by region or route, color-coded by severity on a map.
3. Flight Service by phone — Call 1-800-WX-BRIEF and ask the briefer to read you any reports along your route. It is part of their job, and most briefers appreciate the question.
4. In-flight radio — Monitor flight service on 122.0 or 122.2 and ask for recent reports. Note: the old en route flight advisory service, Flight Watch, was discontinued in 2016. Call flight service directly instead.

How Do I File a Pilot Report?

This is the part most pilots skip. Roughly 95% of general aviation pilots never file, while consuming reports filed by the other 5%.

You do not need the encoded format. You do not need a special form. Plain English is fine — the receiver encodes it for you.

Contact the nearest flight service station or the controller providing flight following. Here is how it sounds:

“Cessna 752 Sierra Mike, pilot report.”

“Go ahead with your report.”

“Cessna 752 Sierra Mike, pilot report. Cessna 172 over Centralia at 5,500. Ceiling broken at 4,500, overcast at 7,000. Smooth ride. Visibility about 8 miles in haze. Outside air temperature plus 4 Celsius.”

That is the entire transaction. Within minutes, the report is available to every pilot, dispatcher, and briefer in the country.

What Should I Include in a PIREP?

The minimum is position, altitude, and the one observation worth sharing. You do not need every element on every report. Useful fields include:

• Position (over a VOR, airport, or city)
• Altitude
• Sky conditions with specific layer altitudes
• Ride quality (smooth, light chop, moderate turbulence)
• Visibility and restrictions (haze, smoke)
• Outside air temperature
• Icing with type and intensity
• Wind at altitude if known

If your report is only about turbulence, just report turbulence. If it is only about cloud tops, just report tops.

What About Icing and Cloud Top Reports?

For instrument pilots, cloud top and icing reports are pure gold. If you climb through a layer and break out at 6,200 feet, say so — there is a pilot below wondering whether to request a higher altitude to get on top.

For icing, use the standard language:

• Intensity: trace, light, moderate, severe
• Type: clear ice or rime ice
• Altitude band: for example, “trace rime between 3,000 and 4,000”

Icing reports save lives. They are the single most valuable piece of information you can give to the pilot behind you.

How Often Should I File?

Build a personal standard of one PIREP per flight. Many pilots file one within the first 30 minutes of cruise as a default — position, altitude, cloud situation, ride. Two minutes of radio time.

File additional reports if conditions change or you encounter anything unexpected. Even “no significant weather” is useful — it confirms the forecast and tells the next pilot the model was right.

Common Mistakes Pilots Make With PIREPs

1. Waiting for something dramatic. Routine reports are valuable. The system needs them.
2. Trying to use the encoded format. Plain English is fine. Flight service encodes it for you.
3. Hesitating to bother flight service. This is exactly what flight service exists for.
4. Feeling uncertain about estimates. If bases look like 3,000, say 3,000. “Light bumps that occasionally bounce my coffee” is useful.
5. Treating reading and filing as separate skills. They are the same skill. The system is reciprocal — you only get out what you put in.

A Real-World Scenario

A 100-hour private pilot plans a 140-nautical-mile flight to a fly-in breakfast. The 6:30 a.m. briefing shows clear above 12,000, light winds, visibility greater than 10. Thirty minutes after a 7:45 departure, an unforecast haze layer appears. Visibility drops to about three miles. No clouds, not IMC — but nothing the forecast captured.

The pilot lands safely and eats pancakes. If no PIREP gets filed, the next pilot launching toward that same breakfast sees the same clean forecast, makes the same plan, and flies into the same haze. With less experience, that pilot might panic or end up scud running.

That chain of events — forecast missed the conditions, earlier pilots did not report it, a later pilot got surprised — appears in a significant number of general aviation accident reports.

Key Takeaways

• PIREPs are eyewitness weather data filed by pilots in flight — the most current and location-specific information in the system.
• Two types exist: UA for routine, UUA for urgent hazards like severe turbulence, severe icing, wind shear, or volcanic ash.
• Plain English is acceptable when filing — call flight service or your flight-following controller and describe what you see.
• Only about 5% of GA pilots file regularly, so every report you contribute meaningfully improves the data available to others.
• Make one PIREP per flight a personal standard — position, altitude, and one observation worth sharing.