Super El Niño Forecast: 90% Chance of Record US Weather Disruption by Winter 2026

A potentially record-breaking El Niño is set to develop this fall, combining with an immense Pacific heatwave to reshape US weather patterns through early 2027. The National Oceanic and Atmospheric Administration reports a greater than 90% chance of a very strong El Niño between September and January, with climate scientists estimating a 70% likelihood it will become the strongest on record since 1950. The dual warming pattern will bring above-average temperatures across most of the country, severe coastal flooding in California, and extreme weather events that could persist well into 2027.

Why this El Niño is different

Two separate warming patterns are converging in the Pacific. A massive marine heatwave that formed in May 2025 is already pushing surface temperatures 3 to 4 degrees Celsius (5.4 to 7.2 degrees Fahrenheit) above normal, according to Andrew Leising, a research oceanographer at NOAA. Layered on top is an El Niño that is intensifying faster than usual. Climate scientist Daniel Swain of UC San Diego estimates a 70% likelihood this event will become the strongest on record later this year, likely peaking between October and December. The combination is rare. The last comparable event was over eight decades ago.

Temperature and rainfall outlook across the US

NOAA’s Climate Prediction Center forecasts above-average temperatures across most of the contiguous United States during fall 2026. The strongest warming signal appears in the Pacific Northwest and northern Rockies. Above-normal temperatures are also favored across the West, Great Plains, Gulf Coast, Northeast, and Mid-Atlantic. No area of the Lower 48 is expected to see below-normal temperatures this fall. For precipitation, the highest odds of wetter-than-normal conditions are focused on the Southwest, including Arizona and New Mexico, as well as parts of the Southeast.

California braces for historic coastal flooding

California faces the most severe near-term impacts. Coastal water levels are already 15 centimeters (5.9 inches) above mean sea level due to the marine heatwave. Patrick Barnard, research director of the Center for Coastal Climate Resilience at UC Santa Cruz, warns that sea levels will rise another 15 to 30 centimeters (5.9 to 11.8 inches) above normal during this El Niño. Every 5 to 10 centimeters of sea level rise doubles flooding frequency for most coastal communities. Barnard states this will create historically high flood risk peaking this winter. Los Angeles County officials are preparing for heavy rains, damaging floods, debris flows from burn scar areas, beach erosion, and high surf. Areas burned by the January 2025 fires, including Altadena and Pacific Palisades-Malibu, face heightened risk of mudflows and debris flows.

Global impacts and record temperatures expected

The super El Niño will amplify long-term climate change effects globally. By increasing heat and water vapor in Earth’s atmosphere and shifting storm tracks, the event will likely trigger significant regional drought and flood events plus extreme heat worldwide. Climate scientists warn that record-breaking global temperatures and extreme weather events are highly likely during 2026 and 2027. Coral reefs in the tropical Pacific are already showing stress. Researcher Kristina Tietjen reported that waters around Kiritimati atoll have already warmed 3 to 4 degrees Celsius above normal, and nearly half of the island’s remaining corals had bleached as of August 2026.

Final Thoughts

With a 90% probability of a very strong El Niño and a 70% chance it becomes the strongest on record, US residents should prepare for above-average temperatures nationwide, severe coastal flooding in California, and extreme weather through 2027. Local governments are already mobilizing resources.

FAQs

Disclaimer:

The content shared by Meyka AI PTY LTD is solely for research and informational purposes.  Meyka is not a financial advisory service, and the information provided should not be considered investment or trading advice.