Graphical Forecast for Aviation

Friday, September 8, 2017

Matt Gabbard, CFII, Ferry Pilot

Matt has been flying for over two decades and has extensive knowledge of different aircraft and avionics, he is a talented photographer and enjoys traveling, history and astronomy. 

Quote to live by: "Whatever you are, be a good one." ~ Abraham Lincoln


From my Desk to the Sky... Graphical Forcast for Aviation

As of this writing (September 2017), a venerable weather product from the National Weather Service (NWS) that has seen decades of service to pilots and other aviation professionals is about to retire.

On October 10, 2017, the NWS will officially cease publishing the Aviation Area Forecast (FA). 

I am pretty happy about that. Taking the FA’s place is the new Graphical Forecast for Aviation (GFA), found on NOAA’s Aviation Weather Center website (www.aviationweather.gov). According to the FAA’s InFO (Information for Operators) no. 17013, “GFAs cover the CONUS from the surface up to 42,000 feet (ft) mean sea level (MSL).” One of the primary reasons for discontinuing the FAs is that so much of the information included in them is available elsewhere within the NWS. While the FA will still exist in the Gulf of Mexico, Alaska, Hawaii and the Caribbean, pilots flying in the Contiguous US will benefit from the vast number of tools, colorful display and interactive features of the GFA.

That’s why I like it. I am a visual learner. I tend to remember a visual image, and when it comes to weather, having a three-dimensional picture of weather patterns and systems will be extremely helpful. 

 
The GFA can be divided into two main features: forecast and current observations/warnings:  
 
Most pilots will be concerned with what they can expect – weather forecasts for the time of their departure – and they will be able to do so from their departure time up to 15 hours into the future. There is a time slider at the top of the page that allows the user to select the desired forecast time:   
 
 
Once selected, a wide range of weather products can be chosen: TAFs, ceiling/visibility, clouds, precip/weather, thunderstorms, winds, turbulence and icing. If the user would like to look back in time to get an idea of the weather trend (big picture) along his or her route of flight, the “Obs/Warn” button should be pressed. Doing so will allow the pilot to select, on the same time slider, up to 14 hours in the past. The array of products available in this feature are METAR, precip/weather, ceiling/visibility, pireps and radar/satellite. Whether using the forecast feature or the current observations/warnings feature, the “Settings” button will take the user to a menu which allows him or her to tailor the map to his or her liking.
 

Features here include the opacity of warnings and forecasts over the map, the type of base map (terrain, satellite, etc.), and map overlay items (VORs, airports, airways, etc.). The possibilities and combinations are seemingly endless. 

 
Several of the weather products, whether for current/past conditions or for forecasted, are color coded. For example, if I select the ceiling/visibility feature on the forecast page, and then select the “FLT CAT” button, I can see that LIFR is depicted as purple, IFR as pink, and MVFR as blue. The same applies to visibility (though with a few more shades of those colors – see the legend) and ceiling. VFR areas are transparent – there is no color coding on those areas of the map.
 

One area of concern I’ve seen others talk about is the inability of the GFA to accurately predict cloud tops, which could be a concern for IFR operations flying at and below FL180.

 
A warning on the GFA’s information page says “NOTE: the color-coded grid and the grid circles [on the GFA map displays] are model-derived data. Users should check TAFs for forecast conditions.” Cloud tops are included in the forecast data, but computer models (specifically the NOAA Rapid Refresh Model [RAP] cloud fraction) are responsible for the output. Humans are not directly involved, and this could be an issue during days with lots of convective activity. As I write this, there is a scattered layer of clouds at 4,300, but the GFA says the LEX area should be clear (the grid circles on the GFA map). While it’s not an unsafe flying day, there’s a pretty big leap from SKC and SCT043. But overall, I think being able to see color coded areas of scattered, broken or overcast clouds, along with the grid circles, will be helpful for pilots – with the caveat that pilots need to gather more information (METARs, TAFs, Pireps) to have a complete picture of the cloud cover for their route of flight. 
 
I just pulled up the GFA on my little Motorola smart phone and could access the features of the tool, albeit with a small screen to view it on. This new forecasting tool is designed to be accessed on the aviationweather.gov website, so there is some concern that it may not be compatible with other flight planning apps and/or devices, unless one is on that specific website.
 

But I can tell much thought has gone into the design of the GFA, and I am confident the powers that be will adapt it to be functional across a wider array of platforms.

 
The new Graphical Forecast for Aviation is something that I believe will be useful to aviation professionals for a long time. Yes, it has a few shortcomings and bugs to work out, but I believe the pros outweigh the cons as of now. The main question now is if anyone will throw the old FA a retirement party. I doubt it.