Sonoma County will test its emergency warning systems twice this week, starting Monday with SoCo Alert calls to all subscribers, followed by more targeted cellphone, radio and television warnings in select areas Wednesday.

The phone calls to SoCo Alert subscribers and those with landlines will begin around 6 p.m. Monday. To sign up, go to socoalert.com.

Wireless emergency alerts will then go out to residents in Healdsburg, as well as Guerneville, Penngrove, Roseland and the Glen Ellen-Kenwood area, on Wednesday between 10 a.m. and noon. Recipients can expect a special tone, vibration and text on their cellphones. Local radio and TV stations also will broadcast a test message around noon.

County staff and local first responder agencies will be evaluating the test messages to check their effectiveness. Recipients can follow a link in the test message to complete a web survey. Field observers also will be placed strategically around the county to capture feedback, while a random sampling of people will be contacted to see if they received the alert or were aware of the test before it was conducted Wednesday.

You can reach Staff Writer Kevin Fixler at 707-521-5336 or at kevin.fixler@pressdemocrat.com. On Twitter @kfixler.