Forum 2/2003

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Introductory Page


Mesoscale NWP

Managing Metadata

Object Data System

GPS Forecasting

Data Distribution

Weather Products


Recent Publications

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Nita Fullerton

Will von Dauster
John Osborn

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2/2003 Forum - ATCC By Dennis Rodgers and Gregory Pratt

FSL is currently in the initial phase of a four-phase project designed to address unmet or newly identified weather information needs of the Federal Aviation Administration (FAA) Traffic Management Unit (TMU) in the following air traffic weather-related hazard areas:

  • Phase 1 – Convective;
  • Phase 2 – Icing;
  • Phase 3 – Turbulence;
  • Phase 4 – Ceiling and Visibility.

Each phase will address the tactical (0 – 1 hour) and strategic (2 – 6 hour) application of the above products to help the TMU decision-maker in directing air traffic into and out of Air Route Traffic Control Center (ARTCC) airspace. All phases will be subjected to the iterative process of defining, developing, demonstrating, and evaluating the weather-related hazard graphic and its presentation to Traffic Management users.

This project is sponsored by FAA Air Traffic System Requirements, FAA Aviation Weather Research Program (AWRP), FAA Southwest Region Headquarters, and National Weather Service Southern Region Headquarters. The purpose of this project is to address the requirements that were found in the in-depth FAA study on "Decision-Based Weather Needs for the Air Route Traffic Control Center (ARTCC) Traffic Management Unit." In response to these needs, FSL is is working closely with the Dallas/Fort Worth (ZFW) Traffic Management Unit and Center Weather Service Unit (CWSU) on Phase 1, the Tactical Convective Hazard Product (TCHP) graphic. Approval was granted to demonstrate and evaluate this graphic at Dallas/Fort Worth, since it is nationally recognized as a high-quality facility that has successfully hosted tests and evaluations of other technologies. There is, therefore, a high likelihood of success at this facility with minimal impact to operations. Also, the Dallas/Fort Worth area experiences significant impact to TMU operations from thunderstorms throughout a large portion of the year.

The goal of the TCHP is to consolidate all tactical thunderstorm information into a single graphical product or a limited suite of products for presentation to TMU decision-makers in an easily understood format. The process is designed to capitalize on development of advanced products from the AWRP and to optimize the use of conventional advisories. Through the process of defining, developing, demonstrating, and evaluating the product, feedback from the Dallas/Fort Worth TMU and CWSU participants will help refine the content and presentation. The demonstration and evaluation will expedite fielding of advanced products by obtaining operational input early in the process. When everyone involved agrees that we have a satisfactory product, specific recommendations will be made for national implementation on FAA operational systems, such as the Enhanced Traffic Management System (ETMS) at the Volpe National Transportation Systems Center.

The planned time frame for TCHP development and evaluation is for convective season 2003, beginning with the first seasonal thunderstorm activity. The iterative process of adjusting the definition, reworking the graphic, redemonstrating, and reevaluating the product will continue until there is a consensus among participants. Additional phases of the project will start as soon as sutiable ARTCCs have been identified as good locations for evaluating the weather hazard and agree to participate in this effort.

The current TMU Website,, (Figure 1) is the location where demonstration and evaluation participants will view the TCHP and other products that have been defined and developed into graphics as they become available for demonstration and evaluation. Currently, participants access supporting documentation, publications, contact information, and move to the desired TCHP view for their area concern by clicking on one of the thumbnail displays.

FAA Hazard Product Home Page

Figure 1. Homepage for the FAA Tactical Convective Hazard Product Demonstration and Evaluation Website.

During the demonstration phase, the Traffic Management user will be presented with the product viewer initialized to the default state that was determined in the definition phase (Figure 2). This display will automatically update as new convective products are received, and the user will also have the ability to change views, maps, and data overlays to help in their decision-making process. The demonstration phase will consist of capturing all weather data during the evaluation process, capturing all Traffic Manager mouse clicks, and verifying all convective weather products.

Convective Hazard Display

Figure 2. Default Traffic Management Tactical Convective Hazard display. Default maps: state boundaries, VOR IDs (very high frequency omni-directional radio beacon identifications), Air Route Traffic Control Center (ARTCC) areas, and Dallas/FortWorth (ZFW) TRACON (Terminal Radar Approach Control) area. Default overlays: National Convective Weather Forecast, hazard detection image, hazard tops and movement graphic, and National Convective Weather 1-hour Forecast (blue polygon).

To evaluate the usefulness of the current Tactical Convective Hazard Product, the Traffic Manager will be interviewed by the development team, using the archived datasets, Traffic Manager mouse events, and statistics from the verification of the convective products to help redefine the Tactical Convective Hazard Product graphic. The information gathered during the interview process will be entered into an evaluation form and saved to a database so we can ensure that the process is working and help determine when the Tactical Convective Hazard Product graphic has been defined.

Future efforts in the definition of the Tactical Convective Hazard graphic are to add Center Weather Advisories (CWA), enhance the graphic with human intervention, and remove inconsistencies in the convective weather forecast by allowing collaboration efforts between adjacent Center Weather Service Units and the Aviation Weather Center. CWAs are issued when the Traffic Management airspace will be affected by weather events that may be missed by other weather reports. We feel that the meteorologist can add value by editing the TCHP graphic to better represent the situation. We also believe that inconsistencies between convective weather products can be minimized if forecasters with the same area of concerns work together to remove them.

Another goal of this project is to determine the correct presentation for the Traffic Manager. The simple Tactical Convective Hazard Product graphic may contain information that is necessary in the decision-making process, but may still be too complicated for a nonmeteorologist to decipher in a timely manner. We believe that the end display should be as simple as: "Is this airspace opened or closed to air traffic?". We are currently in the definition and development process focused on impacts to aviation jet routes, airport arrival and departure gates, and high- and super-high sectors (Figure 3). By following the same process as described above for the Tactical Convective Hazard Product graphic, we will determine when areas of airspace used in the guidance of aircraft are impacted by aviation weather hazards. Once this has been defined, we envision a simple gridded display of airspace area versus time that will be colored green when there are no hazards, red when the airspace is impacted, and blue, if the airspace is forecasted to be impacted.

Jet Route Display

Figure 3. Impacted Jet Route display over the Dallas-Fort Worth (ZFW) ARTCC.

The impacted jet route product (Figure 3) is currently ready for demonstration and evaluation. The colors of the jet route line segments are based on the following convective product impact to the route (Figures 4 and 5):

  • Green – No Impact;
  • Yellow – Weather advisory for convection (Convective SIGMET Nowcast);
  • Red – Currently impacted by convection (NCWF Hazard Detection);
  • Blue – 1-hour forecast for convection (NCWF and Convective SIGMET Forecast).

Impacted Jet Route

Figure 4. Impacted Jet Route with C-SIGMET Nowcast.

Impacted Jet Route 2

Figure 5. Impacted Jet Route with Hazard Detection.

Concluding Remarks

Future efforts include adding more aviation-related maps (airport arrival and departure gates, high- and super-high sectors, and playbooks) and determining impact criteria, and also developing the Web-based grid described above. Airport arrival and departure gates, jet routes, and high- and super-high sectors affect flow into and out of airports and national airspace. Playbooks are the alternate routes into the ARTCC airspace when there are impacts to areas of the ARTCC airspace. The Web-based color-coded grid, we believe, is a delivery mechanism that is presented in an easily understood display for the Traffic Manager. The goal is that through the iterative process of defining, developing, demonstrating, and evaluating, the TMU user will not only help in the creation of the end graphic product and presentation, but will also develop confidence in the Hazard product being created.

Note: More information on this topic is available at the following FSL Website -

(Dennis Rodgers is a Meteorologist in the Aviation Division, headed by Dr. Michael Kraus. He can be reached at or 303-497-6933.

Greg Pratt is Chief of the Aviation Systems: Development and Deployment Branch of the Aviation Division. He can be reached at or 303-497-7237.)

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