Pilot reports and the weather observation from someone who is actually up there right now

Every other piece of weather data in your preflight briefing is either a ground-level snapshot or a forecast. METARs observe conditions at the surface. TAFs and prog charts predict what might happen later. Pilot reports (PIREPs) are different — they come from a real pilot, in a real airplane, reporting exactly what they found at a specific altitude, time, and location. That makes them one of the most valuable and most underused tools in your weather briefing.

Once you understand how to read PIREPs and how to file them, you become part of the system that keeps every pilot safer.

What Is a PIREP and Why Should You Care?

A PIREP is a standardized weather observation filed by a pilot in flight. Unlike ground-based instruments, PIREPs describe conditions between the surface and cruising altitude — the airspace you actually fly through.

This fills a critical gap. The METAR at your destination might report ten miles visibility on the ground, but a pilot twenty miles out at three thousand feet could be reporting five miles in haze. A TAF might call for overcast at five thousand, but a pilot who just climbed through reports tops at six thousand five hundred. That three-dimensional picture is something no ground station or forecast model can give you.

How to Decode a PIREP: Field by Field

The encoding follows a standard sequence. Once you learn the order, it reads like a sentence.

Type (UA or UUA) — UA is a routine report. UUA is urgent, triggered by encounters with severe icing, severe turbulence, low-level wind shear, tornadoes, or volcanic ash. If you see UUA, pay close attention.

Location (/OV) — Where the pilot was, given as a distance and direction from a VOR or navaid. Example: OV DEN090025 means 25 nautical miles east of the Denver VOR.

Time (/TM) — Reported in Zulu. A report from 30 minutes ago is highly reliable. A report from six hours ago may still show trends, but conditions could have changed entirely.

Flight Level (/FL) — Altitude in hundreds of feet. FL060 means 6,000 feet. FL120 means 12,000 feet. Weather changes with altitude, so match the report’s altitude to your planned cruising altitude.

Aircraft Type (/TP) — More important than most pilots realize. A Boeing 767 reporting light turbulence might feel like moderate turbulence in a Cessna 172. Mentally adjust every report for your aircraft’s size and weight.

Sky Condition (/SK) — Cloud bases, tops, and coverage as observed by the pilot. This tells you how thick a layer is and where the gaps are — information that can make or break a VFR go/no-go decision.

Weather and Visibility (/WX) — Rain, snow, haze, mist, and the pilot’s flight visibility, which may differ significantly from surface observations.

Temperature (/TA) — Critical for icing assessment. If the temperature at your planned altitude is near freezing and there is visible moisture, you have an icing environment.

Wind (/WV) — Direction and speed at altitude. This is a real-world check on the winds aloft forecast. A forecast calling for westerly winds at 20 knots might actually be gusting to 35 from the southwest — and that changes your fuel burn, your groundspeed, and possibly your route.

Turbulence (/TB) — Scaled from light (noticeable but not uncomfortable) to moderate (difficulty maintaining altitude) to severe (momentary loss of control possible) to extreme (violent tossing, structural damage possible). Most student pilots should think twice about flying in anything beyond light turbulence.

Icing (/IC) — Scaled from trace (barely visible) to light (slow accumulation, manageable with deice equipment) to moderate (rapid accumulation, hazardous even in short encounters) to severe (deice equipment cannot keep up). If you fly a typical training aircraft, you have zero deice equipment. Any icing report at your planned altitude along your route is a serious red flag.

Where to Find PIREPs During Your Briefing

• 1-800-WX-BRIEF: Briefers are required to include PIREPs as part of a standard weather briefing
• ForeFlight and similar EFBs: Plot PIREPs on the map and filter by recency
• Aviationweather.gov: The National Weather Service PIREP plotting tool displays reports geographically

How a Single PIREP Can Change Your Go/No-Go Decision

Consider this scenario. You are planning a 120-nautical-mile cross-country to the west. METARs report clear skies and ten miles visibility. The TAF looks good. Winds aloft are manageable. Everything says go.

Then you pull up PIREPs along your route and find one from 40 minutes ago: a Piper Cherokee at 5,500 feet, about 60 miles along your course, reporting moderate turbulence and light icing in clouds with tops at 7,000 feet. Temperature at altitude: minus 2°C.

That pilot is in roughly the same airplane as you, at roughly your planned altitude, and found conditions that are uncomfortable at best and hazardous at worst. The METARs did not reveal this. The TAF did not reveal this. The PIREP did.

Your options: fly lower if terrain permits, wait for conditions to improve, pick a different route, or make the no-go call entirely. Without that PIREP, you would have launched into conditions that looked great on paper but had a hazard waiting in the middle.

How PIREPs Factor Into Your Checkride

The Airman Certification Standards (ACS) for the private pilot certificate specifically list pilot reports as weather information you must be able to obtain, read, and analyze. When your DPE asks you to brief the weather for your cross-country, do not just cover METARs and TAFs. Pull up the PIREPs. Discuss what other pilots are reporting along the route.

Also discuss what the absence of PIREPs might mean. No reports along your route does not necessarily mean good conditions — it might mean nobody has filed one. If a SIGMET is active for severe icing in an area and zero PIREPs exist from that area, smart pilots saw the advisory and stayed away. That silence is itself a kind of weather report.

How to File a PIREP (and When You Should)

Any pilot can file a PIREP, and the FAA actively encourages it. You do not need to be an airline captain.

How to file:

• Contact Flight Service on 122.0 or the appropriate frequency and say you have a pilot report — they will walk you through the format
• Call 1-800-WX-BRIEF after landing
• File online through Flight Service

When to file:

• Conditions differ from what was forecast
• You encounter turbulence at any level
• You observe icing
• Cloud tops or bases differ significantly from the forecast
• The ride is remarkably smooth when turbulence was forecast — confirming good conditions is just as valuable as reporting bad ones

Every PIREP you file helps another pilot make a better decision. A student pilot you will never meet might be sitting at their home field right now, deciding whether to go, and your report from 30 minutes ago could be the information that keeps them safe.

How to Evaluate PIREPs: Look for Patterns

A single report of light turbulence might reflect one pilot’s experience in one spot. But three or four reports in the same area, all reporting moderate turbulence within the last hour — that is a pattern you can rely on. The more reports saying the same thing, the more weight they carry.

Key Takeaways

• PIREPs are the only weather product that comes from a pilot actually in the air at a specific altitude, time, and location
• Always match the report’s altitude and aircraft type to your planned flight — conditions vary dramatically by altitude, and turbulence hits light aircraft harder than heavy jets
• Fresh PIREPs (under an hour old) are the most reliable; older reports still show trends but should be weighted less
• The ACS requires you to include PIREPs in your weather analysis — bring them to your checkride briefing
• File a PIREP on every flight where conditions differ from the forecast, including when conditions are better than expected