Testing and Verifying Potential Severe Timing Forecasts in the Hazardous Weather Testbed

The Forecasting A Continuum of Environmental Threats (FACETs) project aims to transform the current dichotomous watch/warning system into a streamlined continuum of probabilistic hazardous weather information. One of the challenges of creating the FACETs continuum is bridging the gap between long lead time convective outlook probabilities and short lead time warning-scale probabilities. Previous work has shown that a majority of convective outlook day events occur in just 4-hours of the 24-hour day. This lead to the development and testing of a forecast product aimed at identifying when that 4-hour period would occur. The latest version of this product, called Potential Severe Timing (PST) areas, was tested in the 2018 HWT with both forecasters and end users. Forecasters expressed a preference for this version of the timing product, as it seemed to be more straightforward and easier to create than previous versions. However, challenges still exist in testing verification techniques and providing guidance for the creation of this timing product.

Emergency managers and broadcast meteorologists also had positive reactions to the PST areas, often citing the need for a way to communicate both area and timing of severe weather. However, they had concerns over how certain weather events would be conveyed with this product. Feedback from both forecasters and end users will be used to develop verification techniques, guidance products and different visualizations of the PST product for future HWT testbeds.