On any given first Tuesday of every month at 10 a.m., Evanston residents might hear the sound of a siren at breakfast, in a meeting or sitting in class.

Those sirens are EvanstonAlerts Emergency Notification System’s monthly siren test. The sirens, which are located in various locations around the city, warn of impending natural disasters. These three-minute tests come in three distinct parts. According to the city’s Warning Signals web page, a minute-long continuous siren precedes one minute of silence and a minute-long wavering siren to indicate an “alert” and a “take cover” signal, respectively.

These continuous signals instruct the community to seek shelter. In the case of severe weather, such as tornadoes, a steady blast will last for three to five minutes. 

Hearing an unusually long signal could indicate a number of emergencies. The city recommends residents look to the Emergency Information web page, the radio station AM 1650 WPXZ-497 and other local distribution networks for more information. 

If the U.S. is under attack, a three-minute wavering or intermittent siren blast indicates that people should take cover, according to the Warning Signals web page.

Residents most often hear Evanston’s snow alerts, which announce incoming snowfall and instruct residents to move cars. In snow emergencies, defined as snowfalls of four or more inches, the City will sound a signal at 7:15 a.m. and 12:15 p.m on the same day.

These alerts indicate that street parking on certain side streets will be unavailable from 8 a.m. to 6 p.m.. Still, on even-numbered dates with a snow warning, residents are unable to park on the side of the street with even-numbered houses, with the same applying for odd days.

To signal snow parking bans, which prohibit parking on main streets or designated snow routes, the city will release a blast at 8:15 p.m. This indicates a snowfall of two or more inches and affects certain streets close to Northwestern’s campus, like Sheridan Road and Sherman Avenue. 

Permanent red, white and blue signs identify where parking is prohibited when the bans are in effect. 

Nearby, Skokie has its own snow parking ban signals, which signal every hour in the event of snow accumulation emergencies. Residents should know Skokie sirens are audible in some Evanston neighborhoods, but they are not subject to these warnings. 

During an emergency, city sirens are an indicator of trouble. The Evanston Office of Emergency Management recommends residents sign up for the city’s EvanstonAlerts emergency text message notification system. 

Email: [email protected]

Twitter: @charlottehrlich

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