GFA Clouds

Still More Out with the Old, In with the New

Over the last few years, I have written a couple of posts about the demise of old weather products and the introduction of their replacements. Well, the National Weather Service is still hard at work (finally) getting rid of some older textual and static products in favor of new, interactive products and products based upon newer forecast models. We’ll take a look at a couple more changes in this post.

Goodbye Area Forecast, Hello Graphical Forecasts for Aviation

In October, 2017, the NWS issued their last text based Area Forecast for the Continental United States. The replacement product, which had been in testing for a while and live for shorter period, is the Graphical Forecasts for Aviation tool, also known as the GFA. It is available at https://aviationweather.gov/gfa.

Bret Koebbe briefly introduced the GFA in an article back in the summer. I’ll give a little more detail here.

The GFA are a set of web-based displays that provide observations and forecasts of weather phenomena critical for aviation safety. The interactive tool replaces the text based Area Forecast (FA) product for the continental United States (CONUS). Coverage is the CONUS from the surface up to FL480 (48,000′).

Multiple fields of interest are combined in categories that the user is able to select from the top of the display.

Data is time synchronized and available hourly from the previous 14 hours to present time on the Observations/Warnings tab, and from 1 to 18 hours in the future (+1 to +18 hours) in the Forecasts category.

Parts of the GFA

Additional information is available in text format when mouse-clicking on the map or using the hover function.

Clouds on the GFAOne of the unique pieces of information that may be found in the GFA which is useful for both visual and instrument pilots is a forecast of the cloud bases and tops for an area. While cloud bases may be found forecast for some airports via a TAF, this information is only good for 5 miles from the center of the runway complex at that airport. TAFs do not include cloud tops. The GFA provides a forecast of both and you can zoom in to see the information for areas not associated with a TAF airport. Clicking on a data block will provide a pop up with more detail. The color coding on the chart can be changed to show an overview of the bases, tops, or amount of cloud coverage. Scrolling the time slider will show you how the clouds will change over time.

Wind, icing and turbulence forecasts are available in 3,000 ft. increments from the surface up to FL180 and in 6,000 ft. increments from FL180 to FL480. Turbulence forecasts are also broken into LO (below FL180) and HI (FL180 and above) graphics. A maximum icing graphic and maximum wind velocity graphic (regardless of altitude) are also available.

The NWS has a short tutorial on the GFA at https://www.youtube.com/watch?v=kLe6Eu3fwS0 and additional info via the Products and Tutorial buttons at https://aviationweather.gov/gfa/help. The GFA has a wealth of weather information and it is well worth your time to explore the tool before needing it for your next flight.

Constant Pressure Analysis Charts

The old Constant Pressure Analysis charts do not appear to be available from the NWS any longer but an updated version of this product with less station detail is still available from Flight Service.

Forecast modelsThere are several constant pressure forecast charts available from the NWS using various models by going to https://mag.ncep.noaa.gov/model-guidance-model-area.php and selecting the model area (such as NAMER or CONUS) and one of the available models to use. These forecast charts have replaced the NWS analysis charts. The new products are future oriented (forecasts) rather than an historical analysis of radiosonde, aircraft, and satellite data.

For the new products, there is a View Product Description button on many of the pages to explain the information from the available models or forecast chart. Given the variations between the models and products available, their discussion is beyond the scope of this post but they are worth taking a look at to find your favorites.

Conclusion

For many years, change in aviation was a slow process and it really still is, but change does come and all of us need to keep up. While many of us, myself included, were concerned about the loss of the Area Forecast for our operations at non-TAF airports, the GFA does seem to fit the bill as a replacement. The Constant Pressure Analysis charts were a more hard core weather product likely only reviewed by the geekiest of weather geeks, again, myself included, but the new forecast charts are leading the way into the future. I think there may have been some improvements.