After a year of reviewing high-resolution satellite imagery, radar data, and storm-chaser video, SalticalWx and I have completed a forensic analysis of the April 26, 2024, Iowa tornado family that impacted Treynor, Minden, Shelby, and Harlan.
Our analysis suggests the two currently mapped tornado tracks may instead represent five distinct tornadoes, with multiple rapid non-occluding cyclic mesocyclogenesis (NOCM) cycles occurring in quick succession.
Our proposed analysis is:
- Treynor, Iowa EF3 (145 mph) | 5:08-5:25 PM CDT
- Bentley, Iowa EF0 (74 mph) | 5:26-5:30 PM CDT
- Minden, Iowa EF0 (85 mph) | 5:34-5:39 PM CDT
- Minden, Iowa EF3 (160 mph) | 5:39-5:52 PM CDT
- Harlan, Iowa EF3 (140 mph) | 5:53-6:35 PM CDT
The evidence is based on high-resolution satellite imagery, cycloidal debris marks, radar data, and triangulated storm-chaser video. These rapid cycles occurred so close together that they likely produced the appearance of one continuous damage path in several locations.
We are sharing our findings with NWS Omaha shortly for their consideration. Regardless of any future changes, this was an incredibly fascinating case study in tornado evolution and rapid cycling.