November 5, 2017 Ohio Tornado Outbreak (313)

Zach Sefcovic, National Weather Service, Cleveland, Ohio

Cory Mottice, National Weather Service

Nick Greenawalt, National Weather Service



On November 5, 2017, an intense quasi-linear convective system (QLCS) swept across the National Weather Service (NWS) Cleveland, Ohio county warning area (CWA). This QLCS produced extensive wind damage across the NWS Cleveland CWA with maximum wind gusts of over 100 mph in some of the most heavily impacted areas. In addition, NWS survey teams confirmed 14 tornadoes across the NWS Cleveland CWA. Of these tornadoes, three were classified as strong EF-2 tornadoes. With 17 tornadoes confirmed across the state of Ohio, this tornado event is one of the largest November tornado outbreaks across Ohio in recorded history.

This study will analyze the low CAPE, high shear environment that was in place over the region during the event and will provide an in depth analysis of the synoptic and mesoscale features. This study will also illustrate many unique features documented by the KCLE WSR-88D and TLVE TDWR radars during the event and further investigate how external influences such as boundaries and gravity waves may have played a role in tornadogenesis and tornado intensity. Tornadic debris signatures (TDSs) were prevalent during many of the tornadoes, which showed up on average just one minute after touchdown. These signatures played an important role in messaging along with the post analysis and damage survey processes. Key findings on azimuthal shear and how it relates to potential tornado detection will be also be presented. A examination of the post-event surveys and assessments from NWS Cleveland will be discussed including difficulties before, during, and after the event. Finally, there will be a discussion of where this event fits in the climatology of Ohio severe weather and an overview of a routine severe weather season during the fall months.