OTTAWA — Canadians across most of the country will hear the shrill screeching siren of the public alerting system today.

A test message and tone from Alert Ready will be broadcast on television, radio and compatible wireless devices.

Test messages will be issued in nearly every province and territory except Quebec and Saskatchewan at specific times between morning and early afternoon, with Ontario’s test set for Thursday.

The system is typically tested in May and November and is part of Canada’s effort to ensure it works and raise awareness.

There is no option to opt out of the test or actual emergency alerts.

The Alert Ready system issued 28 alerts in Canada as of April 30, for emergencies including Amber Alerts, tornadoes and more.

This report by The Canadian Press was first published May 6, 2026.

The Canadian Press