A tornado that nobody on the ground could find, but radar swore was there, has now officially joined the list of April 17 storms near Marthasville, according to the National Weather Service office in St. Louis. Forecasters say a brief circulation spun from Franklin County into neighboring Warren County, showing up clearly on radar, even though survey teams later came up empty on damage and left the event unrated for now.
In its post-storm summary, the National Weather Service in St. Louis lists the newly added track under Marthasville, noting it stretched about 6.59 miles between roughly 9:31 p.m. and 9:40 p.m. CDT on April 17. The office reports that the circulation produced a debris signature lining up with a weak velocity couplet on radar, but survey crews “were unable to find damage directly associated with the tornado,” leaving peak wind speeds unknown and the tornado without a rating pending final review.
Coverage in the Missourian notes that the additional tornado was folded into the April 17 storm reports and that its path cut across low-lying river-bottom terrain between Franklin and Warren counties. That landscape, the reporting points out, helps explain why radar lit up with debris signals while survey teams struggled to spot clear, continuous ground damage along the route.
How the Marthasville Track Fits the Wider Outbreak
The Marthasville track is just one of several short-lived tornadoes tied to a broader Midwest outbreak on April 17–18. Wikipedia summaries note multiple confirmed tornadoes across Missouri, Illinois, Iowa and Wisconsin as forecasters monitored an atmosphere primed for supercells and damaging winds over the two-day stretch.
What Officials Recommend
Even with no damage or injuries attributed to this particular track, the National Weather Service is reminding residents that survey results are not set in stone. As the office notes in its statement, “The information in this statement is preliminary and subject to change pending final review of the event and publication in NWS Storm Data.” Bottom line for locals: keep an eye on official NWS messages and local emergency channels whenever severe weather threatens.
