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Experimental Graphic Aviation Weather for Alaska

The National Weather Service is looking for your help to provide comments on the Experimental Graphical Forecast for Aviation (GFA) covering Alaska.  This tool has been operational in the rest of the country since 2017, and is now being populated with datasets to cover Alaska.  The public notice announcing the availability of this product indicates that it is anticipated to potentially replace the text-based Area Forecast (FA) for Alaska in the future.  But the GFA really is much more than a replacement for the string of text that used to spit out of a teletype machine.  It is really an integrated display that allows pilots to visualize multiple types of information in a graphical form. This includes aviation forecasts up to 18 hours in the future, and providing current conditions—METARs, PIREPs, satellite and radar products, up to 18 hours in the past.  Along with the increase in the potential amount of weather information provided, there are additional tools for pilots to use to select the specific weather information they are looking for. These tools are different and will take some getting used to but are well worth the time to learn. For example, the ability to display a multi-leg route can help the user apply the forecast conditions to the route they are intending to fly.

Using the GFA
As a new user to the system, it helped me to realize that one first must choose whether to look at the future (Forecast button) or current and past conditions (Obs/Warn button), and that for each of these products, selecting the Map Options button allows the user to change features such as the base map, size and opacity of map features.  This is especially important when dealing with some elements, such as PIREPs.  The default for PIREPs is to display those no older than ninety minutes but using the Map Options control allows one to display them in 90 minute increments back to a maximum of 12 hours.  This is a very dynamic system—each map product has its own legend displayed at the bottom of the frame, and most have different feature settings, allowing a high degree of customization.  I personally like the ability to display airports and rivers, for geographic reference.  Learning the nuances of each map and how to customize them to your preferred view will take time and some willingness to understand the new system.

Graphic Forecast: A view of the Experimental GFA looking at the forecast ceilings and visibility for a route between Fairbanks and Anchorage via Healy River and Talkeetna. Being able to display a multi-leg route helps relate to the forecast conditions along each leg of the flight.

Some of these custom options include controls for layers that allow a user to select times and altitudes to display information specific to those settings.  These options demand some study to ensure you have correctly adjusted your settings to display the desired information.  Winds, turbulence, and icing forecasts can be selected for different altitudes. Care will also be needed when viewing PIREPs.  An altitude selector scale is provided but it might be good initially to use the ALL option to get the complete picture before focusing on a single altitude range.

For those of us long-time users of the Alaska Aviation Weather Unit website, the GFA is different—and will take getting used to.  This system combines point observations such as METARs and PIREPs with graphic layers showing the lateral extent of sky cover and includes yet a third element– spot features that forecast cloud bases, tops, and sky cover at regular intervals.  This last layer shows what we used to get in a paragraph of text for an entire forecast zone, but it is now broken into smaller elements, providing additional spatial resolution (see figure below).

Gridded Forecast: This example shows a forecast predicting sky cover, bases, and tops on a gridded basis. The pilot selected route depicted as the pink line is superimposed along with rivers and public use airports in this example help provide for geographic reference. The legend, displayed at the bottom, is never far away.

This weather evaluation product is highly customizable.  The number of features displayed change as one zooms in and out of the product, while continuing to show the route selected in the first place. I particularly like being able to turn on the major rivers for situational awareness.

Share Your Thoughts
The comment period for this experimental product is slated to run through September, 2022.  Please take some time now, during the short dark days of mid-winter, to try planning some routes you normally fly, and see how this system delivers the data. If you are unfamiliar with the GFA, a short video tutorial is available to help get started.  The Info button at the upper right corner of the window will provide a brief description, with links to the tutorial video, the product description document, and a link to the survey to provide feedback. You may also use the “Contact AWC” link in the “fine print” at the bottom of the page if you want to comment on the product.

NWS wants our feedback.  Using the Survey button near the top right corner of the frame to provide feedback will help the product designers and interface experts at the NWS better understand how to adjust the weather evaluation tool as required for Alaska and ensure the system is user-friendly and meets the needs of pilots. Please also share your thoughts on this system with AOPA by email at [email protected]. The time you invest in this today will impact the quality of the product we have to work with in the future!

 

Experimental Alaska weather product predicts clouds along routes

Update: October 10, 2019–This experimental period has been extended another 30 days, and will be available through November 8th.

A new generation of weather satellites is making it possible to help Alaska pilots anticipate weather along their route of flight.  An experimental Cloud Vertical Cross-Section (CVC) Product shows the estimated extent of cloud cover along a route, as well as whether the clouds contain ice, liquid or supercooled water.  These products are available on an experimental basis from September 11th to November 8th.  Check them out, and help provide feedback!

Background
Imaging sensors on new NOAA weather satellites are supporting R&D activities by NOAA and Colorado State University’s Cooperative Institute for Research in the Atmosphere to create a number of new weather products for Alaska.  While the rest of the country relies primarily on geostationary satellites, parked some 22,000 miles above the equator, they don’t provide very detailed information as you go toward the poles. At Alaska’s latitudes, we are better served with polar-orbiting satellites that make multiple passes per day sweeping over the state a little more than 500 miles overhead, capturing swathes of imagery as they fly by.  Image data from these passes are extracted, processed and used to create a new generation of weather products for Alaska.  Starting in mid-September, one set of these products is available to users for evaluation.

Entry page to the Experimental Cloud Vertical Cross-Section Product. Click on the highlighted link on this page to see what satellite passes covered Alaska.

Cloud Vertical Cross-Section (CVC)Product
Shortly after a satellite passes over a portion of the state, data from the sensors is extracted and processed to created a cross-section product.  Four routes that have been defined, to estimate cloud conditions between the cities of Anchorage and Bethel, Fairbanks and Juneau, plus a route from Fairbanks to Barrow (Utqiagvik).  With each satellite pass that covers some or all of these routes, a cross-section product is generated and made available through a website:

http://rammb.cira.colostate.edu/ramsdis/online/npp_viirs_arctic_aviation.asp

This window shows an animation of satellite passes over Alaska, used to create the CVC Product. It also provides an overview of synoptic weather pattern motion.

Navigating the CVC Product
To get a sense of how these products work, click on Pop-up Loop on the Overview with Flight Routes panel.  This animated loop will show the progression of satellite passes that covered the state, and which passes cover the defined routes.  It also provides a good depiction of the cloud cover over the last day or so. Use the controls on this window to change the animation speed, or to step through individual frames for an overview of weather system motion across the state. Times are listed in both UT and Alaska Daylight Time for your convenience.

A sample product from Anchorage to Fairbanks, depicting cloud conditions expected along the route.

Using the Route Product
After pursuing the overview, select a route of interest.  Either the HTML5 Loop or the Pop-up Loop launches an animation that steps through the products available for the route you picked.  Here too, the animation speed can be adjusted.  Or one can hit STOP and step through each frame individually.  This product is highly derived and is pulling data from several intermediate products that estimate cloud height, the cloud base, as well as the type of cloud they think will be present (water, ice or supercooled liquid).  Notice that at times there is missing data, color coded as light gray. In this case the product is not able to make a prediction.  The cross sections also have a backdrop of the terrain along each routes, and an estimate of the freezing level.

How you can help
As described, these are experimental products, and your help is needed to validate them.  First and foremost, please file Pilot Reports when you are flying anywhere within 50 miles of these routes.  During this experimental period, PIREPs are needed to help the science team learn about their accuracy.  Since they forecast the cloud base, as well as top, PIREPs for better than forecast conditions are needed, as well as those associated with icing, and cloud tops.  In addition, if you have questions or specific feedback, there is a Feedback link on the site which will put you directly in touch with the researchers involved in this effort.

This is an exciting step forward in providing weather information for aviation.  Please try out these new products during the 30 day experiment, and do all you can to help the science team understand how their products are working!