Term

PIREP

Daniel MarkFounder & Editor, Aviatopia
Published Mar 1, 2026Updated Mar 1, 20261 min read

Pilot Report — a report of actual weather conditions encountered in flight, submitted by pilots and used to supplement forecast data.

aviation-glossary

Quick Facts

Type
Pilot Weather Report
Also Known As
PIREP
Used By
Pilots, Dispatchers, ATC

Definition#

PIREP stands for Pilot Report (also written as PIREPs or UA/UUA). It is an observation of actual in-flight conditions — turbulence, icing, wind, cloud tops, and visibility — reported by flight crews.

Why It Matters Operationally#

PIREPs are the only source of real-time conditions between the surface and satellite/radar coverage. They supplement METARs and TAFs, and ATC uses them to advise other pilots of conditions on routes and at altitudes.

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