As the region braces for possible rain and flooding, officials are urging residents to be aware and sign for alerts.
In Santa Barbara County, an area hit hard by deadly mudslides earlier this year, officials are already recommending residents evacuate as storms are expected overnight.
Here, you can find ways to sign up to get emergency alerts on your phone, by count.
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LOS ANGELES COUNTY
Sign up for Alert LA County, which uses telephone companies' 911 database to contact land-lines telephone numbers, whether listed or unlisted, to notify residents and businesses about evacuation orders. The Alert LA County system uses geomapping to send alerts to specific neighborhoods.
NotifyLA is the City of Los Angeles' official mass notification system used to send voice messages, text messages and email messages to residents and businesses when an imminent threat to life or property exists your area. Sign up for alerts from the city of Los Angeles here.
Text any zip code to 888777 to receive real-time alerts and advisories from your local police department and other local agencies.
Sign up here to receive notifications from the VC Alert Emergency Notification System.
The system's database currently includes all listed and unlisted landline telephone numbers that are serviced by AT&T and Verizon. If you would like to be contacted on your home phone, cell phone, work phone, TTY device, email, fax or via instant messaging - you must register that information using the "opt in" portal.
Text your zip code to 888777 to receive real-time alerts and advisories from your local police department and other local agencies.
Orange County residents are urged to register with AlertOC, to receive time-sensitive voice messages, text messages and emails from the county or your city.
AlertOC uses 911 databases from telephone companies, so most landlines will already be in the system. AlertOC is operated by the County of Orange in collaboration with local cities.
Register online at AwareandPrepare.com to receive emergency notifications and alerts via land-lines phones, text messages or email.
The Santa Barbara County Office of Emergency Management also posts updates on its official Twitter account.
SAN BERNARDINO COUNTY
In San Bernardino County, the Telephone Emergency Notification System (TENS) uses listed and unlisted numbers in the region’s 911 database to alert residents of life-threatening emergencies. San Bernardino County updates this database every six months.
However, the 911 database only includes land-line telephones, so other numbers must be registered. If a resident wishes to receive an emergency alert text message on their cell phone or an emergency call on their Voiceover Internet Protocol (VoIP) phone they must register the number in the system here.
Residents who do not have internet access may register by dialing 211 or 1-888-435-7565 to sign up.
Riverside County uses a system called Alert RivCo to alert community members of urgent actions to take during disasters, such as earthquakes, wildfires, and floods. You can sign up here.
Alert RivCo uses 911 databases from telephone companies, so most land lines will already be in the system. To register cellular phones, Voice Over Internet Protocol (VOIP), and email addresses, use the registration portal on Alert RivCo’s website.
Residents can also receive alerts by downloading the Swift911 Public App on their smartphones and registering within the App. Once registered, you can log into both the Public App and web portal at any time to update your contact information. The app is available on iTunes and Google Play.
Corona, Moreno Valley, Palm Springs, Riverside and Temecula have their own alerting system for city residents. Residents in those cities are encouraged to sign up with their local system for emergency alerts.