El Niño in San Diego

The City of San Diego is preparing for significant impacts from an El Niño that the National Weather Service is predicting will intensify during the fall and winter of 2026 and 2027.

Because these conditions have the potential to impact communities across the city, it is critical to understand the risks and take steps to prepare.

Stormwater drainage systems in the public right of way are designed for typical rain events. An excessive amount of rain, especially in a short period of time, could overwhelm the City’s stormwater system and cause flooding.

Stay Ready San Diego! It’s everyone’s responsibility.

What is an El Niño?

The term El Niño (Spanish for "the Child") refers to a warming of the ocean surface, or above-average sea surface temperatures, in the central and eastern tropical Pacific Ocean. The low-level surface winds, which normally blow from east to west along the equator (“easterly winds”), instead weaken or, in some cases, start blowing the other direction (from west to east or “westerly winds”).

Sea surface temperature differences on March 1, 2016. Dark red indicates much warmer water.

What San Diego can Expect from an El Niño

Heavier than usual rainfall – stronger winds, flooding
Coastal impacts – Larger and stronger surf, beach erosion, coastal flooding
Extreme heat
Mudslides
Power outages
Infrastructure impacts
Downed trees
Travel challenges – Hazardous driving conditions, flooded roadways

Do you Live in a Flood Zone?

Ways to be Flood Ready

Storm Preparedness

Places to Cool Down During Extreme Heat

Climate Hazards in San Diego

Preparing Your Family for El Niño

Have a portable emergency go kit. Make sure valuables, documents and medications are readily available and in waterproof containers.
Have an evacuation plan.
Sign up for emergency alerts.
Add emergency apps with alerts to your phone – download Genasys Protect, Alert San Diego, Watch Duty
Monitor weather conditions through alerts and weather forecasts.
Make sure your car is in good condition, check windshield wipers and tires.
Have flashlights handy.
Secure trash and debris.
If traveling, be aware of traffic signal outages, downed power lines and road conditions.

Preparing Your Home and Property for El Niño

Floods can happen anywhere. Most homeowners insurance does not cover flood damage. Flood insurance is a separate policy that can cover buildings, the contents in a building, or both, so it is important to protect your most important assets. Learn more at FloodSmart.gov.

Slopes

Inspect all sloped areas for signs of erosion gullys, surface cracks, and slumping. Inspect buildings, patios, retaining walls, and garden walls for signs of cracking or rotation, which may indicate slope movement has occurred. If signs of slope movement are observed, the property owner may consider contacting a California-licensed geologist or geotechnical engineer for a site inspection.

Bare Ground

Inspect large bare areas that may be sources for mudflows during a storm event. Consider covering or vegetating bare areas prior to the storm season. Consider covering and securing mounds of loose soil or fill material.

Drains and Gutters

Inspect and remove debris from retaining wall drains, surface drains, culverts, and gutters prior to the storm season. Storm water runoff should be directed into appropriate drainage control areas to avoid excessive soil saturation.

Structures

Inspect all structures, including seawalls, revetments, and bulkheads, for signs of distress, loss of material, obstructed drainage, or exposed reinforcing steel, prior to the storm season and after every storm. If significant problems are observed, the property owner may consider contacting a California-licensed engineer for maintenance suggestions.