Pilot reports (PIREPs)

From Transport Canada

Pilot reports (PIREPs) are the only direct source of information on cloud heights, turbulence, visibility, winds and icing between weather reporting stations and at some airports. They’re particularly important on flights below 10,000 feet.

When done properly, PIREPs give valuable information to flight service controllers, weather briefers/forecasters and other pilots. One day, your PIREP could save someone’s life.

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Clearly report worse-than-forecast conditions

“Long River radio, this is Birdman 621. I'm on a VFR flight plan between Centreville and Blanktown. I’ve got a PIREP for you. Turbulence is pretty bad, visibility is dropping quite a bit and clouds are low in places. Looks like I’ll be a little late on my ETA.” 

How much useful information did this pilot share? Did he:

  • Provide his exact location or altitude?
  • Clearly describe the turbulence visibility or cloud base?
  • Explain why his estimated time of arrival is off?

Details on air temperature, cloud types, bases and tops, thunderstorm activity and visibility restrictions are helpful. But clear reports on worse-than-forecast conditions are vital.

How to describe turbulence and icing


Light – Turbulence that momentarily causes slight, erratic changes in altitude and/or attitude. Occupants may feel a slight strain against seat-belts or shoulder straps.

Moderate – Turbulence similar to light turbulence, but more intense. Changes in altitude and/or attitude occur but the aircraft remains in positive control at all times. Occupants feel definite strains against seat-belts.

Severe – Turbulence that causes large, abrupt changes in altitude and/or attitude. It usually causes large variations in indicated airspeed. Occupants are forced violently against seat-belts or shoulder straps.


Light – The rate of accumulation over a long flight may create a problem.

Moderate – Even short exposure could be a hazard, and it is necessary to use de-icing equipment or divert flights.

Severe – De-icing or anti-icing equipment fails to reduce or control the hazard. Divert flights immediately.

Preparing your PIREP

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