During the 2017 Spring Forecasting Experiment in NOAA’s Hazardous Weather Testbed, 62 meteorologists completed a survey designed to test their understanding of forecast uncertainty. Survey questions were based on probabilistic forecast guidance provided by the NSSL Experimental Warn-on-Forecast System for ensembles (NEWS-e). A mix of 20 multiple-choice and open-ended questions required participants to explain basic probability and percentile concepts, extract information using graphical representations of uncertainty, and determine what type of weather scenario the graphics depicted. Multiple-choice questions were analyzed using frequency counts, and open-ended questions were analyzed using thematic coding methods. Of the 18 questions that could be scored, 60%–96% of the participants’ responses aligned with the researchers’ intended response. Some of the most challenging questions proved to be those requiring qualitative explanations, such as to explain what the 70th-percentile value of accumulated rainfall represents in an ensemble-based probabilistic forecast. Additionally, participants providing answers not aligning with the intended response oftentimes appeared to consider the given information with a deterministic rather than probabilistic mindset. Applications of a deterministic mindset resulted in tendencies to focus on the worst-case scenario and to modify understanding of probabilistic concepts when presented with different variables. The findings from this survey support the need for improved basic and applied training for the development, interpretation, and use of probabilistic ensemble forecast guidance. Future work should collect data for a larger sample size to examine the knowledge gaps across specific user groups and to guide development of probabilistic forecast training tools.

Southeastern U.S. mobile and manufactured housing (MH) residents are the most tornado-vulnerable subset of the population because of both physical and socioeconomic factors. This study builds upon prior MH resident tornado vulnerability research by statistically and geographically analyzing responses from a survey administered to these residents in the Southeast. Specifically, 257 Alabama and Mississippi MH residents were administered a survey with questions pertaining to their perceived tornado risk and vulnerability, protective action and decision-making, and beliefs about the structural integrity of their homes. Results indicate that, despite the weather and emergency management enterprises consistently suggesting that MH residents evacuate their homes for sturdier shelter during tornado events, more than 50% of MH residents believe their homes are safe sheltering locations. The prevalence of larger MHs in northern Alabama partially influences willingness to shelter within one’s MH, while higher levels of negative affectivity stemming from recent impactful tornadoes in northern Alabama influences people to evacuate their MHs for safety. Study findings also uncovered a perception and vulnerability paradox for these residents: Those who have the means to evacuate their MH often feel they have no need to do so, whereas those who recognize the potential peril of sheltering in their home and want to evacuate often lack the resources and/or self-efficacy to carry out more desirable sheltering plans. Overall, study results provide valuable information for National Weather Service forecasters, emergency managers, and media partners so that they may use it for public outreach and MH resident education.