Collaborative Research: Ensemble Sensitivity Analysis to Investigate Mesoscale Heterogeneity in Southeast US Tornado Events
G. Limpert (Univ. Nebraska), C. Kerr (Univ. Oklahoma/CIMMS), PIs
Plans:
- Further examine the role of rapid destabilization in distinguishing between non-severe and marginally severe events versus higher impact events in high-CAPE and low shear storm environments.
- Apply ensemble sensitivity analysis (ESA) to examine the links between mesoscale heterogeneity, rapid destabilization, and the resulting thunderstorm evolution and severity in several VORTEX-SE events.
- Develop an ensemble weighting system based on ESA that incorporates observations collected after the start of a new forecast cycle that assigns weights to ensemble members based on how well they fit the new observations to generate a weighted ensemble mean for forecasters.
- Evaluate if ensemble weighting improves the forecast skill of guidance that would have been presented to forecasters during the selected VORTEX-SE events using weighted ensemble means versus ensemble thresholding or an unweighted ensemble mean.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-07-06
How Should Forecasters Warn about Tornadoes? Providing a Scientifically Validated Risk Communication Toolkit and Training to the National Weather Service
A. Seate (Univ. of Maryland)
Plans:
- While a substantial focus has been placed on the characteristics of threat messaging (i.e. the message communicating the threat), there is a lack of research toward identifying the most effective strategies for threat messaging (i.e. the avenues and methods for delivering the threat message).
- One experiment will test risk communication by NWS offices in quiet weather. The focus will be on how “humanizing the NWS” and “building threat awareness” messaging approaches impact tornado literacy, trust in the source of the message (NWS), and office satisfaction among the publics. The other experiment will then test how these trust-building strategies in quiet weather and different hazard and safety instruction messaging techniques improve the publics’ responses to a tornado threat.
- Experiments will then be conducted to elucidate how the potential moderating influences of messaging a threat in the context of threat to family members and the convergence or divergence of NWS messaging to the messaging of media partners impact the effects of the previously tested messaging strategies.
- The final product will be a risk communication toolkit to be integrated into several NWS training outlets.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27
VORTEX-SE: Assessment of the Role of Cold Pools in Low- Level Vorticity Production using Direct Observation and Ensemble Sensitivity Analysis
C. Weiss (Texas Tech Univ.), C. Alexander and D. Dowell (NOAA GSL)
Plans:
- Analysis of stesonet data of cold pools of various storms sampled during the Meso18-19 field campaign, including multiple tornadic storms and comparison of cold pool buoyancy observations to past findings.
- Perform HRRRE ESA experiments on several past VORTEX-SE events to analyze impacts of the upstream state on low-level vertical vorticity forecasts in simulated convective storms.
- Use ESA experiments to inform asset placement in future non-classical tornadic storm (NCTS) experiments.
- Transition stesonet observation findings to operations through knowledge transfer and apply ESA findings to tool development (e.g. ensemble subsetting) for operational utility.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27
Achieving Greater Tornado Resilience through Informed Decision-Making about Reinforcing the Anchorage of Mobile and Manufactured Homes
G. Yan (Missouri Univ. Science and Technology), C. Shivers-Williams (CIMMS)
Plans:
- Determine tornadic wind loads on mobile/manufactured homes (MMHs) using large eddy simulations (LESs) and employ a finite element model (FEM) on the modeled MMHs to assess failure modes of MMHs under different designs anchoring systems.
- Develop fragility curves for MMHs to determine their vulnerability to anchoring failure at various tornado intensities.
- Obtain estimates for the cost of properly anchoring MMHs that currently either feature no anchoring, feature only pan anchoring that needs to be upgraded to in-ground anchoring, and corroded anchoring that needs to be updated.
- Perform human-subject study that examines MMH residents’ current knowledge of MMH anchoring practices, tests their willingness to upgrade their MMH anchoring given the information learned in the engineering experiments, and test different methods of educating MMH residents to examine which how different methods of educating MMH residents on proper anchoring techniques affects their willingness to adopt those techniques for their MMHs.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27
Public Interpretation and Use of Evolving Probabilistic Tornado Forecasts in the Southeastern United States
S. Savelli, S. Joslyn (Univ. Washington), J. Demuth, R. Morss (NCAR), K. ash (Univ. Florida)
Plans:
- Test the impact that reducing the accuracy of probabilistic forecast guidance has on the factors such as interpretation, worry, trust, and decision-making.
- Examine whether presenting a range of probabilities provides the same benefit in threat awareness and sheltering actions as presenting probabilistic forecast guidance as discrete values.
- Assess the impacts and practicality of presenting people with evolving tornado probabilities, including within the tornado warning timescale and in the transition from Warn-on-Forecast to tornado warning timescales.
- Conduct in-person interviews to compliment the experiments described above to validate the experiments and gain further insight into the experimental results.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27
Toward an improved understanding of tornado formation within quasi-liniear convective systems (QLCSs)
J. Trapp (Univ. Illinois)
Plans:
- QLCSs tornadoes are most apt to form either through a mechanism involving the tilting of horizontal vorticity and subsequent stretching, or the release of horizontal shearing instability and subsequent stretching.
• We hypothesize that the potential warning lead time, and ultimate tornado strength, will depend on the mode of tornadogenesis, which in turn will depend on the convective environment.
• This and subsidiary hypotheses will be addressed through climatological analyses of tornadic QLCSs, quantification of (operational) Doppler radar data, and assessment of pre-storm environments.
• The project will deliver a quantification of pre-tornadic radar-based characteristics of tornadic QLCSs, and their environments, as a function of genesis mode.
• The deliverables will provide for a baseline situational awareness of the likely evolution of a QLCS event on a given day.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27
Collaborative Research: Real-Time, In Situ Observations of Human Behavior and the Use of Probabilistically-Derived Guidance Among Publics in the U.S. Southeast
J. Friedman (Univ. Oklahoma), S. Jasko, L. Myers, J. Reed (Univ. Alabama)
Plans:
- The goal is to observe 1) the decisions that are taken throughout this temporal continuum; 2) the various sources of information and communication that enter the household, are circulated in the household, and are (at times) communicated out to others in a household’s social network; 3) the preparations and (when relevant) sheltering behaviors of the household; and 4) the longer term memory and recall of these events (as follow-up interviews are conducted days, weeks, and even months after the event).
- To capture naturalistic, in situ feedback from households regarding new probabilistic guidance graphics. Specifically, the study PIs are formally collaborating with both the Storm Prediction Center and the National Severe Storms Laboratory to create ad hoc, probabilistically-generated graphics for specific storm events on the days when the researchers will be in participants’ households.
- To observe how regular people understand probabilistic graphics and information in a familiar geographic setting, in a context in which they have already been alerted to potential storms, and in which they are already receiving local media coverage of potential storms.
- This study focuses on ethnographic, participant observation in order to capture behavioral data associated with naturalistic, in situ observations of study participant households. Background interviews and demographic surveys will be conducted with study participants before the planned field season (Spring 2021 and 2022). When a severe weather event is forecasted, teams of trained research assistants will deploy to their assigned households and conduct a recorded pre-event interview to capture what households know about the forecasted weather, in advance, and what, if any, preparedness actions they have taken.
Formal publications and reports (None)
Project commences Sept 2020
updated 2020-06-27