WHEELER ARMY AIRFIELD, Hawaii - U.S. Army Garrison Hawaii will be upgrading and testing its mass warning notification system June 20-28.

Existing sirens will be modified and in some areas, new sirens will be installed. As a part of the upgrade, all sirens across Army installations will be tested.

Employees, residents and community members off the installation may hear the sirens during the testing period.

In the south region (Aliamanu Military Reservation, Fort Shafter, Fort Shafter Flats, Red Hill and Tripler Army Medical Center), existing sirens will be upgraded and new sirens will be installed June 20-21, and will be tested Wednesday, June 22.

In the north region, (East Range, Field Station Kunia, Helemano Military Reservation, Schofield Barracks and Wheeler Army Airfield) existing sirens will be upgraded and new sirens will be installed June 21-27.

East Range, Helemano Military Reservation and Wheeler Army Airfield sirens will be tested Thursday, June 23.

Field Station Kunia and Schofield Barracks sirens will be tested Friday, June 24. If needed, Schofield Barracks sirens will continue to be tested Monday-Tuesday, June 27 and 28.

During the installation and upgrade, each siren may produce a few quick tones.

During the testing period, each siren will have a prerecorded message stating testing is going on, followed by a bugle call, a thirty-second emergency wail, and another prerecorded message stating the siren was a test.

The entire test will take approximately five minutes per siren, and the tests will take place between 8 a.m.-4:30 p.m. on any given day.

After the siren upgrade, daily bugle calls will continue on select sirens on Fort Shafter, Fort Shafter Flats and Schofield Barracks, and begin at Tripler Army Medical Center and Wheeler Army Airfield.