PIREP Decoder
Paste a U.S. Pilot Weather Report below to decode its location, observation time, altitude, aircraft type and reported weather observations.
What is a PIREP?
A PIREP is a Pilot Weather Report used in the United States to communicate weather conditions observed or encountered by an aircraft. PIREPs provide direct observations that can include clouds, visibility, turbulence, icing, temperature, wind and other operationally important conditions.
The FAA PIREP format is a U.S.-specific reporting format. International aircraft reports use the separate AIREP format, which is not treated as the same grammar by this decoder.
UA and UUA PIREPs
UA identifies a routine PIREP. UUA identifies an urgent PIREP containing weather considered hazardous or potentially hazardous to flight operations.
Urgent reports can include severe or extreme turbulence, severe icing, qualifying low-level wind shear, hail, volcanic ash and certain other hazardous phenomena.
PIREP report groups
The decoder recognizes the FAA slash-group structure, including location (/OV), time (/TM), altitude or flight level (/FL), aircraft type (/TP), sky condition (/SK), weather and flight visibility (/WX), temperature (/TA), wind (/WV), turbulence (/TB), icing (/IC) and remarks (/RM).
Location and altitude
PIREP locations may reference an airport or navigation aid directly, use a radial and distance, or describe a route segment between two references. Altitudes are reported in hundreds of feet MSL unless otherwise specified by the source format.
Turbulence and icing
Turbulence information can include duration, intensity and intensity ranges, CAT, chop, negative reports and reported altitude relationships. Icing decoding includes intensity, icing type and applicable altitude or layer information.
Weather and clouds
PIREP weather information can include flight visibility, weather codes and reported weather layers. Sky-condition information can include cloud amounts, bases, tops, unknown heights, multiple layers and clear-above reports.
Remarks
PIREP remarks may contain specialized contractions or unrestricted plain language. The original remarks remain visible when their meaning is not explicitly decoded.
The documented low-level wind-shear and volcanic-eruption remark forms are also recognized when they appear in a PIREP.
PIREP versus AIREP
PIREP and AIREP are different aircraft-observation formats. This page decodes the U.S. PIREP UA/UUA format. For ARP and ARS aircraft reports, use the AIREP Decoder.
For observed aerodrome weather rather than pilot-reported conditions, use the METAR Decoder.