05/01/2026
The Washtenaw County Emergency Operations Center will be conducting a test of 90 outdoor warning sirens (this includes Chelsea) on May 2, 2026 at 12:00 Noon. These sirens are tested at Noon on the first Saturday of every month from March through October. If there is a threat of severe weather on the day of a test, it will be cancelled. Except for scheduled testing, the sirens will be activated for the following emergencies:
1) The National Weather Service has issued a tornado warning.
2) A severe thunderstorm has been detected with damaging winds of 75 MPH or greater.
3) A hazardous materials accident or other local emergency requires immediate protective action by the public.
4) An attack on the United States is imminent, underway or has recently occurred.
Warning siren activation is a signal to members of the public to immediately go indoors and monitor local Emergency Alert System media outlets for official information. Washtenaw County’s emergency broadcasters are:
WEMU 89.1 FM
WWWW 102.9 FM
WQKL 107.1 FM
WTKA 1050 AM
WLBY 1290 AM
This test does not include sirens within the City of Ann Arbor. Ann Arbor's sirens are tested on the second Tuesday of every month at 1:00 PM.
-WCSO Emergency Services Division
