The safety of our community is a top priority for the City of Naperville. As such, we feel it is necessary to address questions and concerns about Naperville’s outdoor warning sirens and why they did not activate on the morning of Saturday, July 23, 2022.
Naperville’s outdoor warning sirens are automatically activated by notifications from the National Weather Service. Preliminary reports from the National Weather Service indicate that the EF-0 tornado hit Naperville between 5:40 and 5:46 a.m.. City staff members have determined that the National Weather Service never issued a tornado warning for the Naperville area before or during this time, which is why the sirens did not activate before or during this tornado.
Immediately following the tornado in Naperville, the National Weather Service did issue a tornado warning at 5:47 a.m. as the storm headed toward Romeoville. That warning included parts of southern Naperville in northern Will County, and the City’s Emergency Management Agency believes that Naperville’s sirens should have sounded at that time. The sirens did not activate, and City staff members are currently investigating why with extreme urgency.
Please know that we share your concerns and are committed to fully investigating the issue and remedying it as well as thoroughly reviewing internal policies and procedures around our outdoor warning systems. We also encourage all residents and business owners to investigate additional means to receive weather alerts inside their homes, such as purchasing a weather radio, downloading an app, or activating Wireless Emergency Alerts on your smart phone.
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