PIREPs: Not Just For Pilots

Pilot weather reports or more simply PIREPs are not just a private conversation between you and a Flight Watch specialist – they are a broadcast to the world. As such, PIREPs are not only consumed by fellow pilots, but they are essential to many other stakeholders in aviation. This includes air traffic controllers, dispatchers and weather forecasters.

In fact, forecasters at the Aviation Weather Center (AWC) in Kansas City, Missouri, are alerted anytime an urgent PIREP is filed. They affectionally call this alert the “Kmart blue light special” since an audible alarm is sounded along with an alarm button that turns blue on their monitor (see below). Moreover, they have to acknowledge that alarm to silence it.

Blue-Light-Special

What you probably were not taught during your primary training is that SIGMETs for severe or extreme turbulence and severe ice live and die by PIREPs. While a forecaster at the AWC can issue a SIGMET solely based on their own detailed weather analysis before any PIREPs begin to surface, such a SIGMET is rarely issued until pilots begin to report those severe conditions. This is evident by reading the SIGMET text. That is, you will often see “RPTD BY ACFT” as shown in this SIGMET for severe turbulence:

WSUS06 KKCI 111855
SFOW WS 111855
SIGMET WHISKEY 2 VALID UNTIL 112255
SIGMET 
OR CA NV AND CSTL WTRS
FROM 40W BKE TO 30N BTY TO 60SW SNS TO 120W ONP TO 40W BKE
OCNL SEV TURB BLW 150. DUE TO STG LOW LVL WNDS AND STG UDDFS AND
LLWS. RPTD BY ACFT. CONDS CONTG BYD 2255Z.

PIREPs are also ingested into two popular automated weather tools, namely, the Current Icing Product (CIP) and Graphical Turbulence Guidance (GTG) product. You can find both of these analyses in the icing and turbulence ForeFlight static imagery collections. PIREPs of icing and turbulence are combined with many other meteorologically significant parameters that help bolster the algorithm’s confidence of the presence or absence of icing conditions and turbulence to produce the hourly CIP and GTG analyses, respectively. Essentially, your PIREPs can help both man and machine.

CIP-GTG

Speaking of PIREPs, when filing one through Lockheed Martin Flight Service or ATC, be sure to be as specific as possible when reporting turbulence or even airframe ice. Use specific radials from a navaid and avoid guesstimating by using cardinal directions such as “northeast” which can result in a large geographic area especially when you are far from the navaid. Try to provide specific altitudes and avoid general reports such as “icing in the climb” or “icing on descent.”

When you are reporting turbulence, imagine that you are holding a cup of coffee. When the turbulence is light, the coffee may slosh around a bit but doesn’t spill. With moderate, the coffee may spill out quite a bit. In severe turbulence, the entire cup of coffee ends in your lap. And extreme turbulence…well, you’ve got more to worry about than a lap full of coffee.

Lastly, when you file a PIREP for turbulence or ice, make sure you report whether you are within or outside of the cloud boundary. This not only helps pilots know if the hazard is associated with clouds, but may also help researchers at a later time. Researchers are often using PIREPs to fine tune a new tool or technique that may one day help you avoid a nasty turbulence or icing encounter.

Keep those PIREPs coming and get your ForeFlight on and fly safe.