Cellphones will sound off across Niagara and the rest of the country.
Alert Ready tests will be taking place today.
It's Canada's emergency alert system, which notifies everyone about child abductions, natural disasters, terrorist attacks and more.
A test alert will be sent out to cellphones, televisions and radios across Ontario, at 2:55 p.m.
A total of 47 alerts have been sent out across Ontario so far this year; 33 tornado warnings and 16 amber alerts.
You can find more information online here.

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