Pilot Weather Reports (PIREPs)

AIM ¶ 7-1-18 Pilot Weather Reports (PIREPs)

AIM 7-1-18 explains when ATC solicits PIREPs, the standard format, and how pilot weather reports are used by ATC, FSS, ARTCC, and the NWS.

In Plain English

Pilot Weather Reports (PIREPs) are firsthand observations you give to ATC about the weather you're actually flying through. Per AIM 7-1-18, FAA facilities are required to solicit PIREPs when these conditions are reported or forecast:

  • Ceilings at or below 5,000 feet
  • Visibility at or below 5 miles (surface or aloft)
  • Thunderstorms and related phenomena
  • Icing of light degree or greater
  • Turbulence of moderate degree or greater
  • Wind shear
  • Reported or forecast volcanic ash clouds

Pilots are urged to volunteer reports on cloud bases/tops/layers, flight visibility, precipitation, visibility restrictions (haze, smoke, dust), winds aloft, and temperature aloft. Make the report to whoever you're talking with — FSS, ARTCC, or terminal ATC. If you can't get one out by radio, call the nearest FSS or Weather Forecast Office after landing.

PIREPs use a standard coded format (TBL 7-1-8). Items 1–6 are always included: station ID, report type (UA/UUA), location (/OV), time (/TM), altitude (/FL), and aircraft type (/TP). Items 7–13 cover sky, weather, temperature, wind, turbulence, icing, and remarks. Don't worry about perfect phraseology — just get the information out so other pilots, ATC, and the NWS can use it for briefings, advisories, and hazardous weather warnings.

AIM Source Text
FAA AIM ¶ 7-1-18
7-1-18. 7-1-18. Pilot Weather Reports (PIREPs) FAA air traffic facilities are required to solicit PIREPs when the following conditions are reported or forecast: ceilings at or below 5,000 feet; visibility at or below 5 miles (surface or aloft); thunderstorms and related phenomena; icing of light degree or greater; turbulence of moderate degree or greater; wind shear and reported or forecast volcanic ash clouds. Pilots are urged to cooperate and promptly volunteer reports of these conditions and other atmospheric data such as: cloud bases, tops and layers; flight visibility; precipitation; visibility restrictions such as haze, smoke and dust; wind at altitude; and temperature aloft. PIREPs should be given to the ground facility with which communications are established; i.e., FSS, ARTCC, or terminal ATC. One of the primary duties of the Inflight position is to serve as a collection point for the exchange of PIREPs with en route aircraft. If pilots are not able to make PIREPs by radio, reporting upon landing of the inflight conditions encountered to the nearest FSS or Weather Forecast Office will be helpful. Some of the uses made of the reports are: The ATCT uses the reports to expedite the flow of air traffic in the vicinity of the field and for hazardous weather avoidance procedures. The FSS uses the reports to brief other pilots, to provide inflight advisories, and weather avoidance information to en route aircraft. The ARTCC uses the reports to expedite the flow of en route traffic, to determine most favorable altitudes, and to issue hazardous weather information within the center's area. The NWS uses the reports to verify or amend conditions contained in aviation forecast and advisories. In some cases, pilot reports of hazardous conditions are the triggering mechanism for the issuance of advisories. They also use the reports for pilot weather briefings. The NWS, other government organizations, the military, and private industry groups use PIREPs for research activities in the study of meteorological phenomena. All air traffic facilities and the NWS forward the reports received from pilots into the weather distribution system to assure the information is made available to all pilots and other interested parties. The FAA, NWS, and other organizations that enter PIREPs into the weather reporting system use the format listed in TBL 7-1-8 . Items 1 through 6 are included in all transmitted PIREPs along with one or more of items 7 through 13. Although the PIREP should be as complete and concise as possible, pilots should not be overly concerned with strict format or phraseology. The important thing is that the information is relayed so other pilots may benefit from your observation. If a portion of the report needs clarification, the ground station will request the information. Completed PIREPs will be transmitted to weather circuits as in the following examples: EXAMPLE- 1. KCMH UA /OV APE 230010/TM 1516/FL085/TP BE20/SK BKN065/WX FV03SM HZ FU/TA 20/TB LGT NOTE- 1. One zero miles southwest of Appleton VOR; time 1516 UTC; altitude eight thousand five hundred; aircraft type BE200; bases of the broken cloud layer is six thousand five hundred; flight visibility 3 miles with haze and smoke; air temperature 20 degrees Celsius; light turbulence. EXAMPLE- 2. KCRW UV /OV KBKW 360015-KCRW/TM 1815/FL120//TP BE99/SK IMC/WX RA/TA M08 /WV 290030/TB LGT-MDT/IC LGT RIME/RM MDT MXD ICG DURC KROA NWBND FL080-100 1750Z NOTE- 2. From 15 miles north of Beckley VOR to Charleston VOR; time 1815 UTC; altitude 12,000 feet; type aircraft, BE-99; in clouds; rain; temperature minus 8 Celsius; wind 290 degrees magnetic at 30 knots; light to moderate turbulence; light rime icing during climb northwestbound from Roanoke, VA, between 8,000 and 10,000 feet at 1750 UTC. For more detailed information on PIREPs, users can refer to the current version of the Aviation Weather Handbook , FAA-H-8083-28. TBL 7-1-8 PIREP Element Code Chart PIREP ELEMENT PIREP CODE CONTENTS 1. 3-letter station identifier XXX Nearest weather reporting location to the reported phenomenon 2. Report type UA or UUA Routine or Urgent PIREP 3. Location /OV In relation to a VOR 4. Time /TM Coordinated Universal Time 5. Altitude /FL Essential for turbulence and icing reports 6. Type Aircraft /TP Essential for turbulence and icing reports 7. Sky cover /SK Cloud height and coverage (sky clear, few, scattered, broken, or overcast) 8. Weather /WX Flight visibility, precipitation, restrictions to visibility, etc. 9. Temperature /TA Degrees Celsius 10. Wind /WV Direction in degrees magnetic north and speed in knots 11. Turbulence /TB See AIM paragraph 7-1-21 12. Icing /IC See AIM paragraph 7-1-19 13. Remarks /RM For reporting elements not included or to clarify previously reported items
Oral Exam Questions a DPE Might Ask
Q1When are FAA air traffic facilities required to solicit PIREPs?
Per AIM 7-1-18, ATC must solicit PIREPs when the following are reported or forecast: ceilings at or below 5,000 feet; visibility at or below 5 miles (surface or aloft); thunderstorms and related phenomena; icing of light degree or greater; turbulence of moderate degree or greater; wind shear; and reported or forecast volcanic ash clouds.
Q2What six items are always included in a transmitted PIREP?
Per AIM 7-1-18 and TBL 7-1-8, every PIREP includes items 1–6: the 3-letter station identifier, report type (UA routine or UUA urgent), location (/OV) relative to a VOR, time in UTC (/TM), altitude/flight level (/FL), and aircraft type (/TP). Additional items (sky, weather, temperature, wind, turbulence, icing, remarks) are added as applicable.
Q3Who uses PIREPs and for what purposes?
Per AIM 7-1-18, the ATCT uses them to expedite traffic flow and for hazardous weather avoidance; FSS uses them to brief pilots and issue inflight advisories; ARTCC uses them to manage en route traffic, determine favorable altitudes, and issue hazardous weather information; and the NWS uses them to verify or amend forecasts, trigger advisories, and support pilot briefings and meteorological research.
Related Paragraphs in AIM Chapter 7
Master the AIM
Stop guessing. Drill it.

Adaptive questions tied to the live AIM + FAR. Mock checkrides predict your DPE pass rate.

5 questions/day free • No credit card
AIM 7-1-18 — Pilot Weather Reports (PIREPs)