News Archive
ATTENTION: This news article is more than 1 year old and information may be outdated.

April 4, 2021

Media Contact

Public Information Unit, 303-441-1500

Emergency warning sirens to be tested beginning Monday, April 5 as part of annual test

April begins peak flood risk season; Emergency warning sirens testing scheduled

Boulder County, Colo. - Outdoor warning sirens will begin audible testing beginning Monday, April 5 at 10 a.m. and 7 p.m in most communities.

The warning alarm test tomorrow is the first of the monthly emergency audible siren tests which take place each year on the first Monday of each month from April through August. The audible siren tests will occur twice on each testing day, at 10 a.m. and 7 p.m., on April 5, May 3, June 7, July 5, and Aug. 2.

Siren tests ensure that all systems and procedures are working properly during the season of peak flood danger. The tests also promote public awareness of the warning sirens located throughout Boulder County. Sirens are meant to reach people that are outside, not indoors.

Louisville, Superior, Erie and Jamestown will participate in the first audible test on April 5, and then opt out for the remaining monthly tests.

The annual siren testing is a good reminder for community members to sign up for emergency alerts at This system allows all community members in Boulder County and all cities within the county to be notified of emergency situations in a variety of ways including on their cell phone, home and work phones and by text messaging and e-mail.

Should Boulder County experience severe weather during one of the planned audible tests, the siren tests for that day may be cancelled. For updated information, visit

Community members are encouraged to review their own emergency preparedness plans and discuss what they would do in the event of a flash flood or other emergency. For more information about personal preparedness, visit

Used to alert community members to potential danger from a flood or other immediate threat, there are 29 outdoor warning sirens in place across Boulder County, including in Boulder, Erie, Jamestown, Lafayette, Louisville, Lyons, Marshall, Eldorado Springs, Superior and the University of Colorado at Boulder.

All Boulder County sirens undergo weekly tests throughout the year, using a software program that performs a “silent” test.

For more information, visit