Walker S. Ashley, Ph.D., CCM

Distinguished Teaching and Presidential Research, Scholarship, and Artistry Professor

Weather, Climate, and Society Research Group

Department of Earth, Atmosphere, and Environment - Northern Illinois University

Certified Consulting Meteorologist (#668) - StormForensics.com

© Steve Larson

 

 

219-D Davis Hall

Northern Illinois University

DeKalb, IL  60115

 

 

 

 

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I am an atmospheric scientist and disaster geographer with interests in extreme weather and societal impacts. My research team uses an interdisciplinary approach, employing techniques that span the social and physical sciences—from qualitative, survey-based research, to remote sensing and GIS, to the use of computer algorithms on remotely sensed data and numerical model output generated via high-performance computing. My scholarship characterizes the distributions of hazardous weather phenomena, their societal impacts, and how, ultimately, disasters will change in the 21st century. The goal is to supply government and industry stakeholders, policy makers, and the public with information necessary to mitigate disasters and build resilience in the face of rapid environmental and societal change.
   

  

How will supercells change this century?

Courses I teach: (next time offered)

MET 291 Field Experience in Meteorology

EAE 306 Severe and Hazardous Weather (Sum. '24)

MET 360 Radar Meteorology (Sp. '25)

EAE 406/506 Science of Disaster (F '25)

MET 444/544 Mesoscale Meteorology (Sp. '25)

EAE 495/790c Adv. Meteorological Applications

 

Journal publications: (Google Scholar citations; Research Gate; ORCID)

Zeeb, A. W., W. S. Ashley, A. M. Haberlie, V. A. Gensini, and A. C. Michaelis, 2024: Supercell precipitation contribution to the United States hydroclimate. International Journal of Climatology. 10.1002/joc.8395 [PDF]

Andrews, M., V. A. Gensini, A. Haberlie, W. S. Ashley, and M. Taszarek, 2024: Climatology of the elevated mixed layer over the contiguous United States and northern Mexico using ERA5: 1979–2021. Journal of Climate, 37, 1833-1851, 10.1175/JCLI-D-23-0517.1 [PDF]

Wallace, B. C., A. M. Haberlie, W. S. Ashley, V. A. Gensini, and A. C. Michaelis, 2023: Decomposing the precipitation response to climate change in convection allowing simulations over the conterminous United States. Earth and Space Science, 10, 10.1029/2023EA003094 [PDF]

Haberlie, A. M., W. S. Ashley, V. A. Gensini, and A. Michaelis, 2023: The ratio of mesoscale convective system precipitation to total precipitation increases in future climate change scenarios. npj Climate and Atmospheric Science, 6, 150, 10.1038/s41612-023-00481-5 [PDF]

Ashley, W. S., A. M. Haberlie, and V. A. Gensini, 2023: The future of supercells in the United States. Bulletin of the American Meteorological Society, 104, E1-21, 10.1175/BAMS-D-22-0027.1 [PDF]

Strader, S. M, W. S. Ashley, A. Haberlie, and K. Kaminski, 2022. Revisiting U.S. nocturnal tornado vulnerability and its influence on tornado impacts. Weather, Climate, and Society, 14, 1147-1163. 10.1175/WCAS-D-22-0020.1 [PDF]

Haberlie, A. M., W. S. Ashley, C. M. Battisto, and V. A. Gensini, 2022: Thunderstorm activity under intermediate and extreme climate change scenarios. Geophysical Research Letters, 49, e2022GL098779. 10.1029/2022GL098779. [PDF]

Gensini, V., A. Haberlie, and W. S. Ashley, 2022: Convection-permitting simulations of historical and possible future climate over the contiguous United States. Climate Dynamics. 10.1007/s00382-022-06306-0 [PDF]

Stevens, B. R., and W. S. Ashley, 2022: Fatal weather-related carbon monoxide poisonings in the United States. Weather, Climate, and Society, 14, 373-386. [PDF]

Gensini, V. A., C. Converse, W. S. Ashley, and M. Taszarek, 2021: Machine learning classification of significant tornadoes and hail in the United States using ERA5 proximity soundings. Weather and Forecasting, 26, 2143–2160. [PDF]

Eboh, H., C. Gallaher, T. Pingel, and W. S. Ashley, 2021: Risk perception in small island developing states: A case study in the Commonwealth of Dominica. Natural Hazards, 105, 889–914. [PDF]

Haberlie, A. M., W. S. Ashley, and M. Karpinski, 2021: Mean storms: Composites of radar reflectivity images during two decades of severe thunderstorm events. International Journal of Climatology, 41, E1738-E1756. 10.1002/joc.6804 [PDF]

Ashley, W. S., A. M. Haberlie, and V. Gensini, 2020: Reduced frequency and size of late twenty-first-century snowstorms over North America. Nature Climate Change, 10, 539-544. [PDF]

Ash, K, M. J. Egnoto, S. M. Strader, W. S. Ashley, D. B. Roueche, K. E. Klockow-McClain, D. Caplen, and M. Dickerson, 2020: Structural forces: Perception and vulnerability factors for tornado sheltering within mobile and manufactured housing in Alabama and Mississippi, USA. Weather, Climate, and Society, 12, 453–472. [PDF]

Ashley, W. S., A. M. Haberlie, and J. Strohm, 2019: A climatology of quasi-linear convective systems and their hazards in the United States. Weather and Forecasting, 34, 1605-1631. [PDF]

Haberlie, A. M., and W. S. Ashley, 2019: A radar-based climatology of mesoscale convective systems in the United States. Journal of Climate, 32, 1591-1606. [PDF]

Haberlie, A. M., and W. S. Ashley, 2019: Climatological representation of mesoscale convective systems in a dynamically downscaled climate simulation. International Journal of Climatology, 39, 1144-1153. [PDF

Strader, S. M., and W. S. Ashley, 2018: Fine-scale assessment of mobile home tornado vulnerability in the Central and Southeast U.S. Weather, Climate, and Society, 10, 797-812. [PDF; "Paper of Note" in BAMS]

Haberlie, A. M., and W. S. Ashley, 2018: Identifying mesoscale convective systems in radar mosaics. Part I. Segmentation and classification. Journal of Applied Meteorology and Climatology, 57, 1575-1598. [PDF]

Haberlie, A. M., and W. S. Ashley, 2018: Identifying mesoscale convective systems in radar mosaics. Part II. Tracking and application. Journal of Applied Meteorology and Climatology, 57, 1599-1621. [PDF]

Strader, S. M., W. S. Ashley, T. J. Pingel, and A. J. Krmenec, 2018: How land use alters the tornado disaster landscape. Applied Geography, 94, 18–29. [PDF]

Freeman, A., and W. S. Ashley, 2017: Changes in the U.S. hurricane disaster landscape: The relationship between risk and exposure. Natural Hazards, 88, 659–682. [PDF]

Ferguson, A. P., and W. S. Ashley, 2017: Spatiotemporal analysis of residential flood exposure in the Atlanta, Georgia metropolitan area. Natural Hazards, 87, 989–1016. [PDF]

Strader, S. M., W. S. Ashley, T. J. Pingel, and A. J. Krmenec, 2017: Projected 21st century changes in tornado exposure, risk, and disaster potential. Climatic Change, 141, 301–313. [PDF] [featured as News & Views piece in Nature Climate Change]

Briley, L. J., W. S. Ashley, R. B. Rood, and A. Krmenec, 2017:  The role of meteorological processes in the description of uncertainty for climate change decision-making. Theoretical and Applied Climatology, 127, 643-654. [PDF]

Strader, S. M., W. S. Ashley, T. J. Pingel, and A. J. Krmenec, 2017: Observed and projected changes in United States tornado exposure. Weather, Climate, and Society, 9, 109-123. [PDF]

Ashley, W. S., and S. M. Strader, 2016: Recipe for disaster: How the dynamic ingredients of risk and exposure are changing the tornado disaster landscape. Bulletin of the American Meteorological Society, 97, 767-786.  [PDF

Fultz, A. J., and W. S. Ashley, 2016: Fatal weather-related general aviation accidents in the United States. Physical Geography, 37, 291-312. [PDF]

Strader, S. M., T. J. Pingel, and W. S. Ashley, 2016: A Monte Carlo model for estimating tornado impacts. Meteorological Applications, 23, 269-281. [PDF]

Haberlie, A., W. S. Ashley, A. Fultz, and S. Eagan, 2016:  The effect of reservoirs on the climatology of warm-season thunderstorms in Southeast Texas, USA. International Journal of Climatology, 36, 1808–1820. [PDF]

Roeder, W. P., B. H. Cummins, K. L. Cummins, R. L. Holle, and W. S. Ashley, 2015:  Lightning fatality risk map of the conterminous United States. Natural Hazards, 79, 1681-1692. [PDF]

Strader, S. M., and W. S. Ashley, 2015: The expanding bull's-eye effect. Weatherwise, 68, 23-29. [PDF; quick explanation of effect]

Ashley, W. S., S. Strader, D. Dziubla, and A. Haberlie, 2015:  Driving blind: Weather-related vision hazards and fatal motor vehicle crashes. Bulletin of the American Meteorological Society, 96, 755-778. [PDF]

Rosencrants, T., and W. S. Ashley, 2015:  Spatiotemporal analysis of tornado exposure in five U.S. metropolitan areas. Natural Hazards, 78, 121-140. [PDF]

Strader, S. M., W. S. Ashley, and J. Walker, 2015: Changes in volcanic hazard exposure in the Northwest USA from 1940 to 2100. Natural Hazards, 77, 1365-1392. [PDF]

Haberlie, A., W. S. Ashley, and T. Pingel, 2015:  The effect of urbanization on the climatology of thunderstorm initiation. Quarterly Journal of the Royal Meteorological Society, 141, 663-675. [PDF]

Strader, S., W. S. Ashley, A. Irizarry, and S. Hall, 2015: A climatology of tornado intensity assessments. Meteorological Applications, 22, 513-524. [PDF]

Ashley, W. S., S. Strader, T. Rosencrants, and A. J. Krmenec, 2014: Spatiotemporal changes in tornado hazard exposure: The case of the expanding bull's eye effect in Chicago, IL. Weather, Climate, and Society, 6, 175-193. [PDF; "Paper of Note" in BAMS; quick explanation of effect].

Strader, S., and W. S. Ashley, 2014: Cloud-to-ground lightning signatures of long-lived tornadic supercells in the Southeastern U.S. on 27-28 April 2011. Physical Geography, 35, 273-296. [PDF]

Stallins, J. A., J. Carpenter, M. Bentley, W. Ashley, and J. Mulholland, 2013: Weekend-weekday aerosols and geographic variability in cloud-to-ground lightning for the urban region of Atlanta, Georgia, USA. Regional Environmental Change. 13, 137-151. [PDF]

Ashley, W. S., M. L. Bentley, and J. A. Stallins, 2012: Urban-induced thunderstorm modification in the Southeast United States. Climatic Change, 113, 481-498. [PDF]

Bentley, M. L., J. A. Stallins, and W. S. Ashley, 2012: Synoptic environments favorable for urban-enhanced convection in Atlanta, Georgia. International Journal of Climatology, 32, 1287-1294. [PDF]

Gensini, V. A., and W. S. Ashley, 2011: Climatology of potentially severe convective environments from the North American regional reanalysis. Electronic Journal of Severe Storms Meteorology, 6(8), 1-40. [PDF]

Paulikas, M. J., and W. S. Ashley, 2011: Thunderstorm hazard vulnerability for the Atlanta, Georgia metropolitan region. Natural Hazards, 58, 1077-1092. [PDF]

Spencer, J. M., and W. S. Ashley, 2011: Avalanche fatalities in the western United States: A comparison of three databases. Natural Hazards, 58, 31-44. [PDF]

Black, A. W., and W. S. Ashley, 2011: The relationship between tornadic and nontornadic convective wind fatalities and warnings. Weather, Climate, and Society, 3, 31-47. [PDF]

Schoen, J., and W. S. Ashley, 2011: A climatology of fatal convective wind events by storm type. Weather and Forecasting, 26, 109-121. [PDF]

Black, A. W., and W. S. Ashley, 2010: Nontornadic convective wind fatalities in the United States. Natural Hazards, 54, 355-366. [PDF]

Gensini, V. A., and W. S. Ashley, 2010: An examination of rip current fatalities in the United States. Natural Hazards, 54, 159-175. [PDF; Formal comment and reply]

Bentley, M. L., W. S. Ashley, and J. A. Stallins, 2010: Climatological radar delineation of urban convection for Atlanta, Georgia. International Journal of Climatology, 30, 1589-1594. [PDF]

Bentley, M., T. Stallins, and W. Ashley, 2010: The Atlanta thunderstorm effect. Weatherwise, 63, 24-29. [PDF]

Ashley, W. S., and C. W. Gilson, 2009:  A reassessment of U.S. lightning mortality. Bulletin of the American Meteorological Society, 90, 1501–1518. [PDF]

Ashley, W. S., A. J. Krmenec, and R. Schwantes, 2008:  Vulnerability due to nocturnal tornadoes. Weather and Forecasting, 23, 795-807. [PDF; "Paper of Note" in BAMS]

Ashley, S. T., and W. S. Ashley, 2008:  Flood fatalities in the United States. Journal of Applied Meteorology and Climatology, 47, 805-818. [PDF]

Hall, S. G., and W. S. Ashley, 2008:  The effects of urban sprawl on the vulnerability to a significant tornado impact in northeastern Illinois. Natural Hazards Review, 9, 209-219. [abstract; email for PDF]

Ashley, S. T., and W. S. Ashley, 2008:  The storm morphology of deadly flooding events in the United States. International Journal of Climatology, 28, 493-503. [PDF]

Ashley, W. S., and A. W. Black, 2008:  Fatalities associated with nonconvective high-wind events in the United States. Journal of Applied Meteorology and Climatology, 47, 717-725. [PDF]

Ashley, W. S., 2007:  Spatial and temporal analysis of tornado fatalities in the United States: 1880-2005. Weather and Forecasting, 22, 1214-1228. [PDF]

Ashley, W. S., T. L. Mote, and M. L. Bentley, 2007:  An extensive episode of derecho-producing convective systems in the United States during May-June 1998: A multi-scale analysis and review.  Meteorological Applications, 14, 227-244. [PDF]

Suckling, P. W., and W. S. Ashley, 2006:  Spatial and temporal characteristics of tornado path direction. The Professional Geographer, 58, 20-38. [PDF]

Ashley, W. S., T. L. Mote, and M. L. Bentley, 2005:  On the episodic nature of derecho-producing convective systems in the United States. International Journal of Climatology, 25, 1915-1932. [PDF]

Ashley, W. S., and T. L. Mote, 2005:  Derecho hazards in the United States. Bulletin of the American Meteorological Society, 86, 1577-1592. [PDF]

Ashley, W. S., T. L. Mote, P. G. Dixon, S. L. Trotter, J. D. Durkee, E. J. Powell, and A. J. Grundstein, 2003:  Distribution of mesoscale convective complex rainfall in the United States. Monthly Weather Review, 131, 3003-3017. [PDF]

 
Other selected publications:

Bunkers, M., G. Lackmann, J. Allen, W. Ashley, S. Bieda, K. Calhoun, B. Kirtman, K. Kosiba, K. Mahoney, L. McMurdie, C. Potvin, A. Pu, and E. Ritchie, 2023: Comment-reply exchanges: Trends and suggestions. Weather and Forecasting, 38, 633-636. [PDF]

Bunkers, M., G. Lackmann, J. Allen, W. Ashley, S. Bieda, K. Calhoun, B. Kirtman, K. Kosiba, K. Mahoney, L. McMurdie, C. Potvin, A. Pu, and E. Ritchie, 2023: Advantages to writing shorter articles. Weather and Forecasting, 38, 389-390. [PDF]

Huntington, H. P., E. Archer, W. S. Ashley, S. L. Cutter, M. A. Goldstein, C. Roncoli, and T. L. Spero, 2020: Data Availability Principles and Practice. Weather, Climate, and Society, 12, 647–649.

Ash, K. D., M. J. Egnoto, S. M. Strader, W. S. Ashley, D. B. Roueche, K. E. Klockow-McClain, D. Caplen, and M. Dickerson, 2020:  Are manufactured homes as safe as tornado shelters? Most owners think so. Paper of Note. Bulletin of the American Meteorological Society, 101, 283. [PDF]

Strader, S. M., and W. S. Ashley, 2019:  How mobile home distribution shapes tornado impacts. Paper of Note. Bulletin of the American Meteorological Society, 100, 385-386. [PDF]

Ashley, W. S., and V. Gensini, 2017: Weather, extreme weather, and extreme storms. The International Encyclopedia of Geography. Richardson et al. Eds., Wiley-Blackwell. [PDF]

Ashley, W. S., S. M. Strader, T. Rosencrants, and A. J. Krmenec, 2014: Is the Expanding Bull's Eye Effect leading to greater and more frequent weather disasters? Paper of Note. Bulletin of the American Meteorological Society, 95, 510-511. [PDF]

Ashley, W. S., P. Young, and F. Schwantes, 2013: An inexpensive webcam system for capturing live skyscapes and time-lapse cloudscapes. Preprints, 22nd Symposium on Education, American Meteorological Society. 4 pp. [PDF]

Fuhrmann, C., and W. S. Ashley, 2010: Lightning. Encyclopedia of Geography. B. Warf Ed., SAGE Publications, 1780-1784.

Ashley, W. S., A. Krmenenc, and F. Schwantes, 2008: Vulnerability due to nocturnal tornadoes. Paper of Note. Bulletin of the American Meteorological Society, 89, 1498-1499. [PDF]

Fuhrmann, C., and W. S. Ashley, 2006: Cloud-to-ground lightning characteristics of derecho-producing convective systems in the central and southern Great Plains. Preprints, 23rd Annual Conference on Severe Local Storms, American Meteorological Society. 6 pp. [PDF]

 
Funded contracts/grants:

Understanding and Mitigating Future Weather and Climate Risks to Agriculture. With V. Gensini. Community Project Funding, National Oceanic and Atmospheric Administration, 2022-2024.

Faster, Clearer, Stronger Communication and Action: Building IWT and Vulnerable Resident Connections to Improve Severe Weather Literacy and Outcomes. With S. Strader (Villanova), A. Haberlie, and J. Henderson (TTU). National Oceanic and Atmospheric Administration, 2021-2024.

Weather/Climate Modeling, Data Science and Analytics. With V. Gensini, A. Haberlie, and A. Michaelis. Public-private partnership with a mutual company, 2020-2023.

Collaborative Research: Observed and Future Dynamically Downscaled Estimates of Precipitation Associated with Mesoscale Convective Systems.  With V. Gensini, A. Haberlie, and R. Schumacher (CSU). National Science Foundation, Climate & Large-scale Dynamics Program and Physical & Dynamic Meteorology Program, 2017-2023.

Tornadoes and Mobile Homes: An Inter-science Approach to Reducing Vulnerabilities and Improving Capacities for the Southeast's Most Susceptible Population.  With S. Strader (Villanova) and K. Klockow (CIMMS). National Oceanic and Atmospheric Administration, 2017-2020.

Collaborative Research: Climatological and Event-based Radar Delineation of UHI Convection for Urban Corridors within the Southeastern U.S.  With M. Bentley and J. Stallins. National Science Foundation, Geography & Regional Science Program and Physical & Dynamic Meteorology Program, 2007-2012.

NIU Undergraduate Research and Apprenticeship Program. Spring 2006, fall 2006-spring 2007, fall 2007-spring 2008, fall 2008-spring 2009, fall 2009-spring 2010, fall 2010-spring 2011, fall 2011-spring 2012, fall 2012-spring 2013, fall 2013-spring 2014, fall 2014-spring 2015.

NIU Research and Artistry Grant. Summer 2006, summer 2008, summer 2014, summer 2017.

NIU Undergraduate Research Assistantship. Summer 2014, spring 2015.

NIU Student Engagement Fund. Summer 2015, fall 2015, fall 2016, fall 2017.

NIU Great Journeys Assistantship. Fall 2014-spring 2015, fall 2015-spring 2016.

  
Former and current graduate students:
Advisor: Soren Hall, M.S. 2006 (U.S. Army Corps of Engineers); Alan Black, M.S. 2008 (Assistant Professor, SIU-Edwardsville); Monica Zappa, M.S. 2009 (Gilbert F. White Award; Osmar Racing); Chris Gilson, M.S. 2009 (Spectrum Networks); Joe Schoen, M.S. 2009 (Geneva High School); Jeremy Spencer, M.S. 2009 (Professor of Instruction, University of Akron); Marius Paulikas, M.S. 2010 (Instructor, Bowling Green State University); Victor Gensini, M.S. 2010 (Associate Professor, NIU); Andrew King, M.S. 2011 (BP); Laura Briley, M.S. 2012 (Great Lakes Integrated Sciences + Assessments Center); Troy Rosencrants, M.S. 2013 (Geographic Information Systems Center, University of Michigan-Flint); Kristina Rohrbach, M.S. 2013 (Gilbert F. White Award; City of St. Charles); Andrew Fultz, M.S. 2015 (Air Balance); Stephen Strader, Ph.D. 2016, M.S. 2012 (Associate Professor, Villanova University; NIU Outstanding Thesis Award); Alex Haberlie, Ph.D. 2018, M.S. 2014 (Assistant Professor, NIU; NIU Outstanding Thesis Award; Dissertation Completion Fellowship); Ashley Freeman, M.S. 2016 (Allstate); Alex Ferguson, M.S. 2016 (Gilbert F. White Award; NWS Amarillo); Robert Fritzen, M.S. 2017 (Ph.D. candidate, NIU); Kai Funahashi, M.S. 2018 (South Suburban Mayors and Managers Association); Hannah Eboh, M.S. 2018 (Fulbright grantee); Jacob Strohm, M.S. 2019 (UDC); Chris Battisto, M.S. 2021 (NASA); Bailey Stevens, M.S. 2021 (NIU Outstanding Thesis Award; Naval Research Laboratory); Kris Kaminski, M.S. 2023 (NIU Kouba Award; Guy Carpenter); Aaron Zeeb, M.S 2023 (Ph.D. student, CMU); Shane Eagan, M.S. student (NWS Rapid City); Kyle Pittman, Ph.D. student; Skye Leake, Ph.D. student (co-advisor w/ A. Haberlie);

Committee Member: Lauren Lee, M.S., 2006 (GIS Analyst, Whiteside County, IL); Dustin Oltman, M.S., 2007 (Aon Benfield); Cameron Lee, M.S., 2010 (Assistant Professor, Kent State Univ.); Tom Walsh, M.S, 2010 (Lanworth, Inc); Ian Chang, M.S., 2012 (University of Alabama-Huntsville/NASA); Rick DiMaio, M.S., 2013 (Professor, Lewis University); Laura Skelly, M.S., 2013 (Skelly's Farm Market); Adam Dawson, M.S., 2013 (Aon Benfield); Al Marinaro, M.S., 2015 (Maxar Technologies); Steven Chun, M.S., 2017 (Verizon); Cody Converse, M.S., 2020 (Wisconsin DNR); Robert Fritzen, Ph.D. candidate (WIU); Jillian Goodin, M.S. 2023 (NWS); Sylvia Stinnett, M.S. 2023 (Ph.D. student NIU); Margo Andrews, M.S. 2023 (Ph.D. student NIU); Logan Bundy, Ph.D. student; Jeremy Corner, M.S. student; Ben Warren, M.S. student

 
Awards, Honors, and Positions:

Weather and Forecasting Editor (2023+)

NIU Presidential Research, Scholarship and Artistry Professor (2021-2025)

Illinois Science & Technology Coalition Researcher to Know (2021)

NIU CLAS Distinguished Faculty Award (2020)

AMS Walter Orr Roberts Lecturer in Interdisciplinary Sciences (2020)

Weather, Climate, and Society Editor (2019+)

NIU Presidential Teaching Professor (2018-2022); NIU Distinguished Teaching Professor (2022+)

NIU David Raymond Technology in Teaching Award (2017)

AMS Weather, Climate, and Society Editor's Award (2016)

NIU Distinguished Graduate Faculty Award (2016)

Bulletin of the American Meteorological Society Papers of Note (2008, 2014, 2019, 2020)

Certified Consulting Meteorologist #668 (2010+)

Education:
Ph.D. (2005) University of Georgia

M.S. (2000) University of Nebraska

B.S. (1997) University of Georgia

A.S. (1995) Young Harris College

What is a chubasco? A violent squall with thunder and lightning, encountered during the rainy season along the west coast of Central America.