The 8th Conference on Aviation, Range, and Aerospace Meteorology


R G. Hallowell, MIT Lincoln Lab, Lexington, MA; and M. M. Wolfson, B. E. Forman, M. P. Moore, B. A. Crowe, T. M. Rotz, D. W. Miller, and T. C. Carty

A significant fraction of air traffic delay in the U.S. is caused by thunderstorms. Aviation users have indicated that a 30-60 minute forecast of precipitation would be very useful for alleviating delay by allowing controllers and dispatchers to anticipate gate and runway closures and reopenings.

The FAA Aviation Weather Research program has established the Convective Weather Product Development Team (PDT) to study the aviation convective weather problem. As part of this PDT, MIT Lincoln Laboratory has developed and is demonstrating an experimental aviation convective weather forecast product at Dallas/Ft. Worth (DFW) International Airport. The forecast product delivers animated loops of the past weather and forecasts of precipitation out to one hour.

The experimental system utilizes a full resolution 2-D map of the Vertically Integrated Liquid (VIL) water made from NEXRAD wide-band data for the base precipitation map. (NEXRAD wide-band data is available through the ITWS prototype operating at DFW.) The "Growth and Decay Tracker" (Wolfson, 1998) is executed on successive NEXRAD filtered images to obtain the motion of large-scale features in the radar data. The resultant vectors are used to advect the raw weather image, producing a precipitation forecast in ten-minute steps out to one hour. These 2-D images are then displayed using a combination of Tcl/Tk graphics, GIF images, and HTML. The final product is provided to users through a private web page. Direct line connections are used for Air Traffic positions in Dallas, while the Internet is used for all other users (primarily airlines).

Users are shown a two-tone representation of the probability that the forecasted precipitation will be of moderate [VIP Level 3 (38 dBz)] intensity or greater. Users may select 50 NM (terminal) or 200 NM (regional) scales, and loops of past weather and forecast images from 30 minutes in the past to 60 minutes in the future. Images are also made available via FTP for sites that wish to display the images on their own internal networks. In addition, the web page contains real-time scoring information based on the algorithm's past performance, enabling users to understand when the algorithm has been working well and when it has not.

This paper presents details of the Terminal Convective Weather Forecast Demonstration ongoing at DFW and discusses how users are utilizing the new system to improve aviation efficiency.


Wolfson, M.W., 1999: "The Growth & Decay Storm Tracker". Abstract modified to this conference.

* This work was sponsored by the Federal Aviation Administration. The views expressed are those of the authors and do not reflect the official policy or position of the U.S. Government.

+ Opinions, interpretations, conclusions and recommendations are those of the authors and are not necessarily endorsed by the United States Air Force

The 8th Conference on Aviation, Range, and Aerospace Meteorology