Pilot Reports (PIREP)

Pilots are urged to volunteer reports of cloud tops, upper cloud layers, cruising level wind velocity, and other meteorological information which may be significant to safe or comfortable flight conditions. The information is also used by meteorologists to confirm or amend aviation weather forecasts. PIREPs less than one hour old that contain information about conditions considered to be a hazard to aviation are broadcast immediately to aircraft in the affected area and will be included in subsequent scheduled weather broadcasts. PIREPs are also transmitted under the headings “UACN10” for normal PIREPs and “UACN01” or “UUA” for urgent PIREPs.

Sample

UACN10 CYXU 032133 YZ UA /OV YXU 090010 /TM 2120 /FL080 /TP PA31 /SK 020BKN040 110OVC /TA ‐12 /WV 030045 /TB MDT BLO 040 /IC LGT RIME 020‐040 /RM NIL TURB CYYZ‐CYHM

UACN10 Message Type: Regular PIREP. Urgent PIREPs are encoded as UACN01 or UUA.
CYXU Issuing office: London FIC.
032133 Date/Time of Issue: 3rd day of the month, at 2133Z.
YZ FIR: Toronto. If the PIREP extends into an adjacent FIR, both FIRs will be indicated.
UA /OV YXU 090010 Location: London VOR 090° radial, 10 NM. PIREP location will be reported with reference to a NAVAID, airport or geographic coordinates (latitude/ longitude).
/TM 2120 Time of PIREP: 2120Z
/FL080 Altitude: 8,000 feet ASL. Altitude may also be reported as “DURD” (during descent), “DURC” (during climb) or “UNKN” (unknown).
/TP PA31 Aircraft Type: Piper Navajo (PA31).
/SK 020BKN 040 110OVC Sky Cover: First layer of cloud based at 2,000 feet with tops at 4,000 feet ASL. Second layer of cloud based at 11,000 feet ASL.
/TA -12 Air Temperature: -12°C.
/WV 030045 Wind Velocity: Wind direction 030° true, wind speed 45 knots. Wind direction reported by pilots in degrees magnetic will subsequently be converted to degrees true for inclusion in PIREP.
/TB MDT BLO 040 Turbulence: Moderate turbulence below 4,000 feet ASL.
/IC LGT RIME 020-040 Icing: Light rime icing (in cloud) between 2,000 feet ASL and 4,000 feet ASL.
/RM NIL TURB CYYZ-CYHM Remarks: No turbulence encountered between Toronto and Hamilton.