The declaration is precautionary and does not by itself mean a specific storm or evacuation has been ordered. The city says its planning covers heavier rainfall, flooding, powerful surf, beach erosion, mudslides, extreme heat, power outages and other hazards.
San Diego's Citywide El Niño Preparedness Working Group has been planning sandbag distribution, evacuation routes, emergency access, debris removal, shoreline protection and possible Emergency Operations Center activation since the summer.
Residents and businesses should follow official city alerts and weather warnings and prepare before conditions worsen. The mayor's announcement does not identify a new application, payment or resident deadline.