28 | SEPTEMBER 2019 FLYINGMAG.COMPILOT’S DISCRETION The Reverse Weather Briefing
ISTOCK/^ TRIFONOV_EVGENIYone location? We’re not quite there yet, so it’s up to the pilot
to determine a f low that works best.
Before going on, I don’t want to completely discount
the Flight Service NextGen weather briefing available
in ForeFlight and 1800wxbrief.com because this is still
a great way to get a complete weather briefing all in one
spot. It’s where I teach my students to start when learning
to f ly and perfect for the casual f lyer who isn’t interested
in all the advanced model-based forecasts.
So I’ve taken a new approach when f lying IFR, which
I call the “reverse weather briefing,” accepting the fact
that I’ll be going on a bit of a scavenger hunt for weather
products based on the conditions of the day.
The “reverse” part of the briefing gets its name because
it starts with the graphical depiction of the Pilot Report
layer on an interactive map to take a big-picture view of the
location and severity of hazards being reported, such as tur-
bulence, icing and wind shear. You can quickly interpret the
condition, intensity and altitude of each report based on the
color, symbol and altitude code listed to get a good feel for
the potential trouble spots.Next, add the radar imagery as a second overlay to
determine which of the pireps were likely caused by
precipitation—which more often than not is the key
indicator for where you’re likely to find thunderstorms,
heav y ice, turbulence and low-IFR conditions. I use
this as a jumping-off point to then decide which other
advanced charts to reference, either in the same app or
one of the NWS websites.See lots of icing pireps? It’s time to check out the icing
forecast layers, severity/probability charts, temps aloft,
freezing level charts and airmets. Finding lots of turbu-
lence pireps in a convective weather system? Head over
to the Convective Outlook, Convective Forecast, sigmets,
TAFs and NWS Forecast Discussion to learn more about
the strength of the system and how the timing of expected
development will impact your route.
I’ve found that by approaching the briefing with a look
at actual conditions first, you can more accurately iden-
tify potential weather hazards early and direct your focus
to specialty charts to better understand the big picture.
There are just as many days you’ll find only a handful
of pireps with high pressure and clear skies along your
route, greatly reducing the number of charts and reports
you’ll need to reference for that day’s briefing.
The reverse weather briefing has its limitations depending
on when and where you are flying. First, it works better for
the IFR pilot flying through active weather systems, so VFR
pilots may not find it as effective when focused on visibility
and the height of cloud bases. Then, there are many times
you’ll find nearly all the pireps are coming from the airlines,
so you’ll have to mentally calibrate the intensity level with
your airplane type in mind. Light or moderate turbulence
or ice reported from a Boeing 767 will have a greater effect
on the lighter and slower airframe of a Cessna 182. There
are also times of day and regions in the United States when
the flight volume is light or nonexistent, so starting off with
pireps won’t work well.
We’re closing in on the technology that will soon enable
affordable internet connectivity in the cockpit, allowing
you to quickly submit pireps in flight from your main EFB
app. The Aerovie app from Appareo can do this now. This
will lead to a substantial jump in the number of pireps gen-
erated every hour, making this briefing method even more
effective. I’d suspect too that the NWS would be able to use
the increased volume of real data to improve its weather
modeling and improve forecasting along the way.I USE THIS AS A JUMPING-OFF POINT
TO THEN DECIDE WHICH OTHER
ADVANCED CHARTS TO REFERENCE,
EITHER IN THE SAME APP OR ONE
OF THE NWS WEBSITES.
General aviation pilots may want to rethink how they go about
gathering preflight weather information.