El Niño pushes San Francisco ocean temperatures to late-season record

Overview

Updated 1 hour ago

Water off San Francisco is warmer than any recorded at this point in the year. Near the Farallon Islands, sea surface temperatures reached about 65°F in early November, roughly 10°F above normal, according to climate scientist Daniel Swain.

The warmth comes from El Niño pushing equatorial water up the California coast. It matters because cold upwelling normally feeds the region's marine food web. Warmer water can push fish and seabirds elsewhere and raise sea levels along the coast.

Why it matters

Warmer coastal water can raise sea levels and disrupt the marine food web that supports California fisheries and seabirds.

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Key Indicators

65–66°F

Peak sea surface temperature near Farallon Islands

Early November reading, about 10°F above normal.

10°F

Above normal

Departure from typical November water temperature of about 56°F.

2–3°F

Beyond previous late-year record

Swain says temperatures are 2–3°F past any prior reading after Nov. 1.

83%

Chance of strongest El Niño on record

NOAA estimate for January–March 2027, from a Scripps summary.

Voices

Curated perspectives — historical figures and your fellow readers.

People Involved

Daniel Swain

Climate scientist, University of California Agriculture and Natural Resources

Active; analyzing record ocean temperatures

Organizations Involved

Scripps Institution of Oceanography

Research institution

Maintains Shore Stations Program data cited in the report

Runs long-running ocean temperature and sea-level monitoring programs at Scripps Pier and along the California coast.

National Oceanic and Atmospheric Administration

Federal agency

Forecasts El Niño conditions and monitors sea levels

Issues El Niño forecasts and runs tide gauges that track coastal sea level.

Timeline

September 2026 November 2026

5 events Latest: Yesterday

Tap a bar to jump to that date

November 2026
KQED reports record late-season ocean heat
Latest Report

KQED reports record late-season ocean heat off San Francisco coast.
Yesterday
Swain calls Farallon heat 'off the charts'
Statement

Swain says Farallon water is 'off the charts' and still warming.
7 days ago
October 2026
San Pedro tide gauge breaks sea-level record
Measurement

San Pedro gauge hits 8.02 feet, then 8.19 feet Oct. 27, breaking 2005 record.
October 26th, 2026
NOAA forecasts strong El Niño
Forecast

NOAA estimates 83% chance of strong El Niño from January to March 2027.
October 2026
September 2026
Scripps Pier sets monthly sea-level record
Measurement

Scripps Pier tide gauge records highest monthly mean sea level ever.
September 2026

Scenarios

King tides push seawater into California coastal communities

Likely Resolves by Nov 30, 2026

Discussed by: National Weather Service and NOAA tide forecasts

Warmer water raises baseline sea level. If Thanksgiving king tides coincide with swell or rain, low-lying streets and beaches from San Francisco to Orange County could flood. National Weather Service coastal flood advisories would be the first signal.

Marine heat wave disrupts California fisheries

Possible Resolves by Q1 2027

Discussed by: Scripps Institution of Oceanography and California Department of Fish and Wildlife

Warm water reduces cold upwelling, which can shift fish and squid away from usual grounds. If the pattern persists, regulators could restrict a fishery or document unusual catch changes.

El Niño stays strong into spring, keeping ocean temperatures elevated

Likely Resolves by Apr 30, 2027

Discussed by: NOAA Climate Prediction Center and Scripps Institution of Oceanography

NOAA's forecast puts high odds on a strong event through early 2027. If equatorial warmth keeps feeding Kelvin waves toward California, coastal temperatures may stay above normal and keep sea levels elevated into spring.

Historical Context

3 moments from history that rhyme with this story — and how they unfolded.

1997–1998

1997–98 El Niño (1997–1998)

One of the strongest El Niño events on record brought heavy winter storms to California, caused coastal erosion and mudslides, and disrupted fisheries.

Then

Flooding and wave damage hit coastal communities, and marine species shifted north.

Now

It became a benchmark for forecasting El Niño risks and for tying coastal flooding to ocean warming.

Why this matters now

Today's event is following a similar script: warm equatorial water moving up the coast and raising sea levels.

2015–2016

2015–16 El Niño and marine heat wave (2015–2016)

A strong El Niño coincided with a persistent marine heat wave in the northeast Pacific, often called 'the Blob,' stressing kelp forests and fisheries.

Then

Kelp die-offs and marine mammal strandings were reported, and fisheries shifted.

Now

Scientists began treating marine heat waves as distinct hazards on top of El Niño.

Why this matters now

Scripps says this year's El Niño is arriving on top of a record-breaking marine heat wave, the same compounding pattern.

January 2005