Case Study: Southern Iowa Tornado Outbreak - March 5, 2022

In-depth case study of the localized tornado outbreak that occurred across southern Iowa on March 5, 2022. This video will focus on the supercell that produced the EF4 tornado that tore a 70-mile-long path from Winterset to Newton, IA, impacting southern and eastern portions of Des Moines along the way. On the surface, this event appeared to be a typical cold-core event; however, there had to be some other factors at play that allowed multiple strong or violent to occur. To determine why this event over-performed, I discuss:

*Model forecasts leading up to the event,
*The background synoptic and mesoscale environment before and during the event,
*How the event progressed, including some of my own experience chasing the Winterset supercell,
*Hypotheses for why this event over-performed when, on the surface, it looked like a typical cold-core event, and
*Analog events, including those that yielded storms with similar rapid tornadogenesis, occurred in the same area, and had similar background environments.

Chapters:

0:00 Introduction
3:02 Model data
10:09 Background synoptic/mesoscale environment
14:53 Event progression: initiation/organization
19:44 Winterset supercell: mesocyclone development, Corning tornado
20:54 Winterset supercell: pre-tornado evolution, increase in hail core size/intensity
24:36 Winterset supercell: tornadogenesis, tornado maintenance
28:10 Chariton and Corydon tornadoes
29:14 Winterset supercell: cyclic tornadogenesis, Kellogg and Tama tornadoes
30:08 Characteristics and evolution of low-level shear
37:35 Topographical influences on low-level shear
41:45 Favorable storm characteristics: precipitation venting, streamwise vorticity current
46:06 Analogs
46:31 Analogs (rapid tornadogenesis): March 28, 2020 (Jonesboro, AR, tornado)
50:15 Analogs (rapid tornadogenesis): May 22, 2011 (Joplin, MO, tornado)
53:59 Analogs (geography): June 7, 1953
55:45 Analogs (geography): June 12, 1976
57:47 Analogs (background environment): April 22, 2020 (Springer, OK, tornado)
59:29 Analogs (background environment): April 23, 2021 (Lockett, TX, tornado outbreak)
1:00:34 Conclusions