Specific locations experienced historic heat levels. Salt Lake City reached 109 degrees Fahrenheit on July 12, 2026, marking its hottest temperature since records began in 1874. Washington, D.C. tied its all-time warmest overnight low of 84 degrees Fahrenheit on July 3, 2026. Much of Southern California endured excessive heat warnings during the second week of September 2026.

Sea-surface temperatures in the eastern Pacific Ocean have reached 2 degrees Celsius above average. The National Oceanic and Atmospheric Administration defines sea-surface temperatures 2 degrees Celsius above average as the threshold for a “very strong” El Niño. El Niño has reached “super” status, a classification that has occurred only three other times since 1950. As of September 2026, there have been six super El Niño events in recorded history.

Forecasters expect the current El Niño to become the strongest on record by November or December 2026. Strong El Niño conditions are expected to continue through February 2027 before weakening in the spring. The US Climate Prediction Center forecasts increased odds for hotter-than-normal temperatures across much of the United States through at least the end of September. Computer models indicate a pronounced atmospheric ridge pattern is locking in sustained warmer-than-normal conditions across the United States.

Some computer models suggest temperatures could run 5 to 10 degrees Fahrenheit above normal for the latter half of September in parts of the United States. The greatest odds of above-normal temperatures exist around the Upper Midwest and the Deep South. NOAA's Climate Prediction Center defines the technical onset and strength of El Niño based on sea-surface temperature departures.

Why It Matters

The scale of record-breaking temperatures during the summer of 2026 reflects the intensity of the current climate pattern. With nearly 44,000 record daytime high temperatures and more than 53,000 record-high overnight minimum temperatures recorded during the summer, the data reflects widespread thermal stress across the nation. The designation of “super” status for the El Niño event places it among rare historical occurrences, with only five prior instances in recorded history as of September 2026.

Forecasts indicate that strong El Niño conditions will persist through February 2027, suggesting continued impacts on temperature and precipitation patterns. The expectation that this event could become the strongest on record by late 2026 indicates the potential for further deviations from historical averages in the coming months.

Timeline

On June 1, fisheries off West Coast States and the Highly Migratory Species Fishery saw the El Nino Pacific Loggerhead Conservation Area Closure implemented. NMFS later reopened the Pacific Loggerhead Conservation Area closure because sea surface temperatures in the Southern California Bight for May and June indicated a return to normal. Salt Lake City reached 109 degrees Fahrenheit on July 12, 2026, its hottest temperature since records began in 1874.

What's New

Additional reporting confirms that the average temperature for the contiguous United States in August 2026 was 75.6°F, 3.5°F above the 20th-century average, while the average for meteorological summer was 74.4°F, 3.0°F above average. Both August and summer were the warmest in the 132-year record. Research titled “Summer Surface Warming Driven by the Strong El Niño in the South China Sea” was published in 2023.

December temperatures in San Antonio average 0.6 degrees colder during active El Niño events than during non-El Niño years. San Antonio temperatures average 1.4 degrees colder in January during active El Niño events compared to non-El Niño winters. San Antonio temperatures fall by an average of 1.3 degrees in February during active El Niño events compared to non-El Niño winters.

How Sources Differ

Data from ncei.noaa.gov states the average temperature for the contiguous United States in August 2026 was 75.6°F, 3.5°F above the 20th-century average, while the average for meteorological summer was 74.4°F, 3.0°F above average. National weather station data report nearly 44,000 record daytime high temperatures were recorded at weather stations across the United States during the summer of 2026. Data from ncei.noaa.gov also states the average temperature for the contiguous United States in August 2026 was 75.6°F, 3.5°F above the 20th-century average, while National weather station data report more than 53,000 record-high overnight minimum temperatures were recorded at weather stations across the United States during the summer of 2026.