Overview

• The Aug. 28, 1990 storm killed 29 people, injured more than 300 and devastated Plainfield, Crest Hill and Joliet along a roughly 16-mile path.
• Classified as an F5, it remains the only U.S. tornado of that strength recorded in August and its rain-wrapped funnel was never photographed.
• On that day the National Weather Service issued only a severe thunderstorm warning minutes before impact and did not post a tornado watch until after most damage occurred.
• Doppler radar was deployed nationally within two years, improving detection, and modern systems now deliver more targeted warnings to cellphones with richer data.
• Local training and reporting expanded through efforts such as DuPage County’s seminar with the College of DuPage, and officials emphasize preparedness with weather radios and refined warning criteria that blend radar, ground reports and atmospheric signals as Plainfield’s mayor commemorates the anniversary.