Northern Tornadoes Project

The Northern Tornadoes Project is a research initiative at the University of Western Ontario that focuses on tornadoes and other severe convective storm-related wind phenomena in Canada. It was founded in 2017 by Greg Kopp and David Sills,^[1][2] with the financial support of Toronto-based social impact fund ImpactWX.^[3]

Background

Recognizing the need to document tornadoes in large areas of Canada with low population density, a pilot project was established in 2017 called the Northern Tornadoes Flyover Project. The objective was to attempt to document tornadoes in Canada's northern forested areas that would otherwise not be identified using an aircraft instrumented with a high-resolution camera flying over areas with suspected storm damage.

Success with documenting 2017 tornadoes, particularly after high-resolution satellite imagery was used to identify a large tornado outbreak in Quebec, led to an expanded pilot project in 2018 - aiming to document all tornadoes in Ontario and any significant tornadoes in other parts of the country. The scope was increased again in 2019 to include all tornadoes across Canada, and the Northern Tornadoes Project (NTP) was officially launched with Sills as director^[4] and Kopp serving as the ImpactWX Chair in Severe Storm Engineering.

In 2024, Kopp and Sills co-founded the Canadian Severe Storms Laboratory (CSSL), a partnership between the University of Western Ontario and ImpactWx launched.^[5][6][7] The work of the NTP, and other projects, continues under the umbrella of the CSSL.

NTP operations and research

The NTP team under Sills detects, assesses and documents all Canadian tornadoes, makes tornado data publicly available via an open data portal and dashboards that can be used to map event data.^[8] It also conducts research using the collected data, including climatology and trend analysis,^[9][10] techniques to improve tornado detection and wind speed estimation,^[8] and tornado warning verification.^[11]

NTP-related scientific publications

Peer-reviewed journal articles

• Sills, D. M. L., G. A. Kopp, L. Elliott, A. Jaffe, E. Sutherland, C. Miller, J. Kunkel, E. Hong, S. Stevenson, and W. Wang, 2020: The Northern Tornadoes Project - uncovering Canada's true tornado climatology.  Bull. Amer. Meteorol. Soc., 101, E2113–E2132, DOI 10.1175/BAMS-D-20-0012.1.^[8]
• Sills, D. M. L., C. S. Durfy, and C. P. E. de Souza, 2022: Are Significant Tornadoes Occurring Later in the Year in Southern Ontario? Geophysical Research Letters, 49, e2021GL096483, DOI 10.1029/2021GL096483.
• Kunkel, J., J. Hanesiak, and D. Sills, 2022: The hunt for missing tornadoes: Using satellite imagery to detect and document historical tornado damage in Canadian forests. J. Applied Meteorology & Climatology, 62, 139–154, DOI 10.1175/JAMC-D-22-0070.1.
• Ibrahim, I., G. A. Kopp, and D. M. L. Sills, 2023: Retrieval of peak thunderstorm wind velocities using WSR-88D weather radars. J. Atmos. Oceanic Technol., 40, 237–251, DOI 10.1175/JTECH-D-22-0028.1.
• Ngui, Y. D., M. R. Najafi, C. P. E. de Souza, and D. M. L. Sills, 2023: Probabilistic assessment of concurrent tornado and storm-related flash flood (TORFF) events. Int. J. Climatol., 43, 4231-4247, DOI 10.1002/joc.8084.
• Stevenson, S. A., C. S. Miller, D. M. L. Sills, G. A. Kopp, D. M. Rhee, and F. T. Lombardo, 2023: Assessment of wind speeds along the damage path of the Alonsa, Manitoba EF4 tornado on 3 August 2018. J. Wind Engineering & Industrial Aerodynamics, 238, 105422, DOI 10.1016/j.jweia.2023.105422.
• Sills, D. M. L and L. Elliott, 2023: Assessment of Tornado Alerting Performance for Canada. Atmos.-Ocean, DOI 10.1080/07055900.2023.2257163.^[11]
• Butt, D. G., A. L. Jaffe, C. S. Miller, G. A. Kopp and D. M. L. Sills, 2024: Automated large-scale tornado treefall detection and directional analysis using machine learning. Artificial Intelligence for the Earth Systems, DOI 10.1175/AIES-D-23-0062.1.
• Miller, C. S., G. A. Kopp, D. M. L. Sills and D. G. Butt, 2024: Estimating Wind Speeds in Tornadoes Using Debris Trajectories of Large Compact Objects. Mon. Wea. Rev., 152, 1859–1881, DOI 10.1175/MWR-D-23-0251.1.
• Butt, D. G., T. A. Newson, C. S. Miller, D. M. L. Sills and G. A. Kopp, 2025: Analysis of forest-based tornadoes using treefall patterns. Mon. Wea. Rev., DOI https://doi.org/10.1175/MWR-D-24-0249.1.
• Sills, D. M. L., and C. S. Miller, 2025: Multi-level in-situ measurements during a direct hit by a significant tornado. Atmosphere-Ocean, DOI 10.1080/07055900.2025.2554837.

Other Scientific Articles

• Sills, D., G. A. Kopp, E. Hong, J. Kennell, A. Jaffe, and L. Elliott, 2018: The Northern Tornadoes Project – overview and initial results. Extended Abstracts, 29th AMS Conference on Severe Local Storms, Stowe, VT, Amer. Meteorol. Soc., Paper 60, 1-6.
• Sills, D., E. Hong, A. Jaffe, S. Stevenson, and G. A. Kopp, 2018: The ‘cross-border’ tornado outbreak of 24 August 2016 – analysis of the two tornadoes in Ontario. Extended Abstracts, 29th AMS Conference on Severe Local Storms, Stowe, VT, Amer. Meteorol. Soc., Paper 180, 1-13.
• Kopp, G., D. Sills and J. Brimelow, 2024: Canada is witnessing more thunderstorm impacts than ever before. The Conversation - Canada Edition. Academic Journalism Society, Toronto, Canada. DOI 10.64628/AAM.756uj4pn6
• Sills, D., and G. Kopp, 2025: It’s challenging to predict extreme thunderstorms — improving this will help reduce their deadly and costly impacts. The Conversation, Academic Journalism Society, DOI 10.64628/AAM.vhrrcxrv6
• Sills, D., L. Elliott, D. Michelson and N. Donaldson, 2025: 'Missed' EF2 tornadoes in Canada and the role of radar. Extended Abstracts, 41st AMS Conference on Radar Meteorology, Toronto, ON, Amer. Meteorol. Soc., Paper 6B.4, 10 pp.

NTP in the media

The work of the NTP has been featured on TV and radio,^{[2][12][9][13][14][15][16][17][18][19][20][10]} newspapers,^{[21][22][23][24][25]} magazines,^[26][27] and podcasts^[28][29] in Canada and the United States.