Communicating Threat Level for Flash Floods in the Hazardous Weather Testbed Hydrology Experiment 2014

The inaugural Hazardous Weather Testbed Hydrology Experiment (HWT-Hydro) was held over a four-week period in July 2014 to assess the use of experimental flash flood prediction models. HWT-Hydro brought together researchers and NWS forecasters in an effort to evaluate the FLASH (Flooded Locations and Simulated Hydrographs) product suite along with other experimental flash flood prediction models. During the testbed, forecasters from across the United States used the tools to issue experimental flash flood watches and warnings. A unique component of the experiment was the introduction of a set of probabilistic and categorical threat attributes to communicate forecast information. For each experimental watch or warning, forecasters assigned a probability of a specific threat level (nuisance and major flooding). At the end of each week, the forecasters participated in a focus group designed to gather feedback about the new threat attributes.

This presentation will cover the findings from a qualitative analysis of the focus group discussions. While the addition of this threat information was viewed in a very positive manner, themes from the discussion included concern for public communications and factors that affected their ability to assign a threat level. Nevertheless, HWT-Hydro participants felt that assigning threat level attributes allowed them to communicate their mental models to forecast consumers.