FDTD Satellite Applications Webinar - Satellite Help Desk

When: 17 April at 1700 UTC

Presenter: Peter Speck (NWS WFO Quad Cities, IA/IL)

Title:  A Not-So-Elevated Supercell from Eastern Iowa to the Chicago Area on 4 April 2023

Summary:

An intense supercell thunderstorm with largely elevated characteristics formed early on the morning of 04 April 2023 in southeast Iowa, and thereafter took a 200+ mile long track that included parts of two major metropolitan areas over the next seven hours. This supercell alone produced significant severe weather along much of its path, including a swath of over 150 large hail reports ranging from one to nearly four inches in diameter, severe wind gusts reaching 90 MPH, and multiple short-lived tornadoes. For such a long-lived storm, the meteorological impetus for this development was subtle, with possibly gravity waves playing a role. Satellite analysis was one means that may have helped identification of these, and this will be explored. 

Also of unique interest is that this storm ultimately displayed surface-based characteristics despite being largely rooted above a pronounced stable layer per observed and model diagnostic soundings. Surface temperatures immediately before storm arrival into the Quad Cities metro area were in the mid 40s, with a 6°C inversion above the near-surface layer through 850 mb. While hail was the most frequent impact from this supercell, the risks of damaging winds and tornadoes were not as low as would be suspected given the presence of the stable low-level atmosphere. As the supercell entered the easternmost portions of the Quad Cities, IA/IL, it produced significant severe wind gusts and short-lived tornadoes for a period. Recent research (Borchardt et al., 2024) has shown numerous cases where such behavior can occur with elevated convection when collocated with mesoscale gravity waves. This case further stressed the need for growing our understanding and use of the conceptual model for what is an “elevated” storm.

A radar, satellite and service-based analysis of this high impact supercell thunderstorm will be provided, along with lessons learned for operational meteorologists, including changing threats and shifting storm motions during its lifecycle. Anticipating such storm morphology, as well as suggestions on communicating shifting threats, will be shared in hopes they can be used by others within the Weather Enterprise. 

Gotowebinar URL:  https://attendee.gotowebinar.com/register/4596487907181051998

Audio Options: VOIP or phone number option available upon webinar registration.

If you are unable to attend these live training events you may find recordings available at: 
http://rammb.cira.colostate.edu/training/visit/satellite_chat/