The stretch of Pacific Ocean off California and the West Coast has never been this warm in June.
Last month, water temperatures in the region ran more than 3 degrees Fahrenheit above the 20th century average, the highest June departure in 177 years of records, according to data from the National Oceanic and Atmospheric Administration published Thursday.
Much of the Pacific Ocean, including waters off California and the tropical Pacific where El Niño is strengthening, ran well above average in June 2026. (ECMWF )
The figure represents a regional monthly average, not a single thermometer reading or one uniform ocean temperature. Actual water temperatures varied considerably along the coast. For local context, NOAA buoy observations averaged about 55 degrees in June 18 miles west of San Francisco and about 66 degrees in the Santa Monica Basin west of Los Angeles.
The record is part of a remarkable buildup of ocean heat across the eastern North Pacific. The region has been running unusually warm for months amid a persistent marine heat wave, and the January-through-June period was also the warmest on record.
Globally, ocean temperatures were also the warmest ever recorded in June.
The extraordinary warmth is unfolding as a historically strong El Niño continues to develop in the tropical Pacific, adding another source of ocean heat and atmospheric disruption heading into the second half of the year.
For California and the West Coast, the combination of already record-warm waters and a very strong El Niño points toward a busy stretch of impacts ahead.
Warmer sea surface temperatures off Baja California and Southern California can load subtropical moisture plumes with more water, increasing the potential for unusual thunderstorm activity and monsoonal surges in the state when the atmospheric pattern steers that moisture north. The monsoonal flow is expected to kick into gear this weekend and persist through next week.
The warm waters can also fuel eastern Pacific tropical cyclones, bringing long-period swells, dangerous surf and remnant tropical moisture north toward California.
The heat is breaking records on land too.
The biggest June story was the historic and deadly heat wave in western Europe. A persistent high-pressure ridge trapped hot air from North Africa over western Europe for more than a week, shattering all-time temperature records in over a dozen countries. Preliminary estimates indicate France recorded more than 2,000 excess deaths during the heat wave. Germany recorded roughly 5,000.
NOAA’s summary of notable weather and climate events for June 2026 shows record or near-record warmth across most of the globe. Global ocean temperatures were the highest ever recorded for the month. (NOAA)
Elsewhere, the Arctic recorded its warmest June ever – the first time the region exceeded a 2 degree Celsius departure from the norm for the month. India recorded one of its driest Junes since 1901, with national rainfall at just 60% of normal. Precipitation also ran below average across much of the western and southwestern United States.
June 2026 marked the 50th consecutive June with global temperatures above the 20th century average. The last below-average June was 1976.
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This article originally published at The Pacific near California has never been this warm in June.