Sept. 20, 2021
ST. CHARLES COUNTY, MO – Starting today, Sept. 20, St. Charles County Regional Emergency Management (REM), in cooperation with the National Weather Service (NWS), is instituting changes to help alert and keep residents safe during severe storms and to cut down on confusion during outdoor warning siren testing.
Following is a breakdown of these changes:
- The NWS will push Wireless Emergency Alert (WEA) notifications to smartphones if a thunderstorm in an area is categorized as “Destructive.” A storm in this category has at least 2.75-inch diameter (baseball-sized) hail and/or 80+ mph winds. The alert notification will be similar to those issued by the NWS during a Tornado Warning.
- When the NWS issues an alert notification for a “Destructive” storm, REM will activate the outdoor warning sirens throughout the county. REM also activates the sirens when the NWS issues a Tornado Warning.
- REM is moving St. Charles County’s monthly outdoor warning siren test from 9 a.m. to 11 a.m. on the first Monday of the month. This will coincide with St. Louis County’s outdoor warning siren testing time to help reduce confusion for those who live and work along the St. Charles and St. Louis county border.
According to the NWS, 13 of the 22 costliest weather disasters in 2020 were severe thunderstorms. This includes the costliest thunderstorm event in U.S. history: The “derecho” in August 2020 that produced straight-line wind damage across several states, including Iowa and Illinois. In some areas, wind gusts during this storm reached over 120 mph. For comparison, an EF-0 tornado has wind speeds of 65-85 mph and an EF-1 tornado has wind speeds of 86-110 mph.
“From 2012 to 2021, there have only been seven thunderstorms categorized as ‘Destructive’ in our county, so this type of severe weather is rare,” Captain Chris Hunt, Director of REM, explains. “However, the derecho demonstrates how destructive storms can create tornado-level damage. As a result, issuing this alert and activating the sirens is necessary to protect our community.”
REM encourages residents to stay alert during any storm event and to have multiple methods to receive emergency alerts and information.
“Along with relying on smartphone notifications, have a NOAA weather radio and stay tuned to news and radio broadcasts,” Captain Hunt says. “Also, it is important to keep in mind that outdoor warning sirens are only meant to be heard outdoors, so they shouldn’t be relied upon as a sole method for notification.”
For more information on severe weather safety and tips to prepare for any emergency, visit sccmo.org/REM.