Creating Ties Between Aviation Forecasting and Warn-on-Forecast System Development

The Warn-on-Forecast System (WoFS) keeps pace with the chaotic nature of thunderstorms via a continual 15-minute data assimilation cycle and the relaunch of ensemble-based, multi-hour probabilistic forecasts every 30 minutes, on a relocatable regional grid. Resulting gains in predictive skill and quantification of uncertainty have proven beneficial to severe weather and flash flood forecasting, particularly at 1–3 hour lead time. WoFS is likely applicable to aviation forecasting, but the product needs of aviation forecasters and decision support needs of aviation customers may differ from related needs in the severe weather realm. With WoFS on a track toward potential operationalization at the NWS, the National Severe Storms Laboratory and Aviation Weather Center are creating ties to inform WoFS development and to understand how its value can best be harnessed for aviation.

Several WoFS aviation use cases were documented and forecasters were surveyed, participated in focus groups, or volunteered their insights as part of a) Aviation Weather Testbed (AWT) experiments in 2022 and 2024, and b) a 4-week WoFS Aviation Experiment in 2024 that was led by the AWT and involved Center Weather Service Units. The WoFS Aviation Experiment enabled study of the logistics of WoFS grid placement and timing to support decision-making in aviation. For example, on 12 July 2024, a WoFS run was initiated at 0300 UTC, a first in the history of WoFS, and was followed by a new domain spun up in the same location at 1500 UTC; sequential runs in the same location was also a WoFS first. Much was also learned about forecaster preferences for WoFS products and potential new products. Aviation forecasters were most often concerned with permeability, and relied on ensemble representations of thunderstorm growth and timing, and mean and probability products for echo tops and lightning. Operations to research relationships forged during the experiment will help inform new WoFS development. A summary permeability product and better-calibrated echo top probabilities have already been suggested.

One area that will need much more study is best practices for applying WoFS to aviation decision making. The NWS aviation weather product suite is mostly schedule- rather than event-driven; WoFS is particularly skillful at short, event-driven lead times. Many aviation customers are accustomed to or prefer deterministic forecasts, which may not take advantage of WoFS’ probabilistic design. There were, however, several instances in the 2024 experiment of forecasters using WoFS to brief partners on-the-fly, or adding/eliminating thunderstorm areas depicted in graphical forecast products such as the Traffic Flow Management Convective Forecast. This presentation will illustrate the newly developing conversation on WoFS in the aviation forecast community.