Articles | Volume 6, issue 3
https://doi.org/10.5194/wcd-6-807-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-6-807-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Jul 2025
Research article |
| 28 Jul 2025
| 28 Jul 2025
Linking weather regimes to the variability of warm-season tornado activity over the United States
Matthew Graber
Department of Climate, Meteorology & Atmospheric Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61820, United States
Department of Climate, Meteorology & Atmospheric Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61820, United States
Robert J. Trapp
Department of Climate, Meteorology & Atmospheric Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61820, United States
Related authors
Matthew Graber, Zhuo Wang, and Robert J. Trapp
EGUsphere, https://doi.org/10.5194/egusphere-2026-536, https://doi.org/10.5194/egusphere-2026-536, 2026
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
Short summary
Short summary
This study aims to seasonally predict springtime tornado activity using a weather-regime-based hybrid model and to identify the physical sources of predictability to explain the results. Tornado outbreaks, days with several tornadoes, exhibit model skill and should be a primary focus of future work given their societal impacts. Low-frequency climate modes are important sources of predictability for weather regimes, providing forecasts of opportunity for springtime tornado outbreaks.
Matthew Graber, Zhuo Wang, and Robert J. Trapp
EGUsphere, https://doi.org/10.5194/egusphere-2026-536, https://doi.org/10.5194/egusphere-2026-536, 2026
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
Short summary
Short summary
This study aims to seasonally predict springtime tornado activity using a weather-regime-based hybrid model and to identify the physical sources of predictability to explain the results. Tornado outbreaks, days with several tornadoes, exhibit model skill and should be a primary focus of future work given their societal impacts. Low-frequency climate modes are important sources of predictability for weather regimes, providing forecasts of opportunity for springtime tornado outbreaks.
Yulan Hong, Stephen W. Nesbitt, Robert J. Trapp, and Larry Di Girolamo
Atmos. Meas. Tech., 16, 1391–1406, https://doi.org/10.5194/amt-16-1391-2023, https://doi.org/10.5194/amt-16-1391-2023, 2023
Short summary
Short summary
Deep convective updrafts form overshooting tops (OTs) when they extend into the upper troposphere and lower stratosphere. An OT often indicates hazardous weather conditions. The global distribution of OTs is useful for understanding global severe weather conditions. The Moderate Resolution Imaging Spectroradiometer (MODIS) on Aqua and Terra satellites provides 2 decades of records on the Earth–atmosphere system with stable orbits, which are used in this study to derive 20-year OT climatology.
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Short summary
This study identifies five warm-season weather regimes (WRs) to investigate the link between tornado activity and large-scale atmospheric circulations. Certain WRs strongly affect tornado activity due to their relationship with the environment. When a WR that positively affects tornado activity persists over multiple days, it further increases the tornado activity probability. The links found highlight the potential application of WRs for developing better seasonal prediction of tornadoes.
This study identifies five warm-season weather regimes (WRs) to investigate the link between...
