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El Niño HubCalifornia storm guide
State of emergency Governor Newsom proclaimed a statewide El Niño state of emergency on Sep 21, and Los Angeles County followed with its own emergency proclamation. Read the Governor's announcement
California resource / Winter 2026–27

El Niño is building

A very strong El Niño is on the way. Plain-language forecasts, a preparation checklist you can track, and the official sources to watch before the first storm.

+2.1°CNiño-3.4, Oct 8
83%+Strong to very strong
Jan–FebTypical peak storm risk
30 daysTypical flood-insurance wait
01 / The outlookWhat forecasters see

What “very strong” means

Forecasters rank El Niño by how far the Niño-3.4 region of the Pacific runs above average. Readings above +2.0°C are generally called very strong, and the latest reading is already past that line.

Weak Moderate Strong Very strong +0.5°C +1.0°C +1.5°C +2.0°C Oct 8 reading: +2.1°C

It's already here

NOAA moved from Watch to Advisory on June 11, 2026. By Oct 8, sea surface temperatures ran more than +4.0°C above average in parts of the eastern equatorial Pacific.

It should last

NOAA expects a strong to very strong El Niño through January–March 2027, with a chance above 83%.

Strength is not a promise

A stronger event shifts the odds toward certain impacts. It does not fix where each storm lands.

02 / CaliforniaPick a region

What it could mean for California

NOAA's Dec–Feb outlook issued Aug 20 placed California in the above-normal category for precipitation. NOAA updates its seasonal outlooks every month, so check the latest map.

The 2015–16 lesson. That El Niño was nearly as strong as 1997–98, yet Southern California stayed drier than forecast because storms tracked farther north. Prepare for a wet winter and treat any single forecast as odds.
03 / The seasonMonth by month

A typical El Niño winter

This is the usual pattern in strong events, not a forecast for specific dates.

Now

Prepare

Clear drains, check roofs, build your kit, and review flood insurance waiting periods.

Nov–Dec

Storm track shifts south

The first atmospheric rivers can arrive. Soils are still dry and burn scars are most exposed.

Jan–Feb

Peak risk

Repeated storms on wet ground raise flood, landslide, and debris-flow danger.

Mar–Apr

Tail and melt

Storms wind down. Snowmelt and swollen rivers stay a concern.

04 / Get readySaved in this browser only

Preparation checklist

Check items off as you go. Your progress saves in this browser only.

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05 / Official sourcesBookmark these

Official sources

For warnings and evacuation orders, trust these over any summary, including this site.

National Weather ServiceForecasts, watches, and warnings by ZIP code. NOAA ENSO DiscussionThe monthly El Niño status and strength forecast. California Nevada River Forecast CenterRiver levels and flood forecasts. Listos CaliforniaEmergency preparedness guides, in many languages. LA County EmergencyCounty alerts, storm updates, and preparedness resources. Genasys ProtectLook up your evacuation zone (Know Your Zone). FloodSmart (FEMA)Flood insurance and risk lookup. USGS Landslide HazardsDebris-flow and landslide information. Caltrans QuickMapLive road closures and chain controls. Ready.gov FloodsWhat to do before, during, and after a flood.

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