The CWS may use sirens to alert you to a possible hazard in your area. It could be for any number of hazards and is sounded to draw your attention away from your daily activities. No matter the hazard, the best first protective action is to Shelter, Shut and Listen. Sirens are tested on the first Wednesday of every month at 11:00am. For a siren location map click here.

To hear an example of a CWS siren sound click here


cell-phone-5Voice, Text and Email alert messages

Click here to register to receive voice, text and email alerts. In addition, the CWS Telephone Emergency Notification System (TENS) is used for call-out in case of emergency.

A computerized system makes telephone calls to the known telephone numbers in the vicinity of the hazard based on the incident specific issues. To stream line for fast activation in emergency, the areas around known places were predefined, so activation is faster.

These predefined areas are the “TENS Zones”. Follow the links below to access the maps for the predefined areas:

Chevron Refinery, Richmond TENS ZONES

Shell TENS zones

Tesoro Refinery TENS ZONES

Phillips Rodeo TENS zones





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wx500NOAA Weather Radio

CWS uses the National Weather Service to provide emergency alerts and information for major non-weather related emergencies. Weather radios are an inexpensive and reliable way to receive these alerts. These devices can be battery powered to provide a means of receiving emergency alerts if your power is out. Learn more about NOAA Weather Radios here.


eas-logo_300Emergency Alert System (EAS) and Wireless Emergency Alerts (WEA)

The CWS is designed to provide specific information directly to the media through the Emergency Alert System. The EAS interrupts TV and radio broadcasts to deliver major local, regional, and national emergency alerts. Following the initial alert, TV and Radio stations provide ongoing status reports and information.

The CWS uses a federal system that sends text alerts to your smartphone during major emergencies, no registration needed! Check with your cell phone service provider to see if your cell phone can receive Wireless Emergency Alerts. To learn more about EAS and WEA click here.