Mysterious ‘Warm Blob‘ Returns to Pacific, raising Questions About Winter Weather
September 16, 2025 – A meaningful and unusual warm water anomaly has re-emerged in the northeast Pacific ocean, prompting concern and investigation from meteorologists and oceanographic agencies. Meteorologist Mike Masco reported on September 15, 2025, that the North Pacific sea surface temperature reached 20°C (68°F) in August, marking a potential record high.
The phenomenon, dubbed “the Blob,” is caused by a combination of factors including warmer air temperatures, shifts in wind patterns, and the El Niño-Southern Oscillation (ENSO), according to the National Park Service. ItS not a new occurrence; a similar marine heatwave developed off the coast of Alaska in 2013, expanding southward and stretching from Alaska to Mexico by the summer of 2014.
NOAA is currently monitoring the growth of this latest iteration, identifying it as the 4th largest marine heatwave since monitoring began in 1982. Their latest update notes a pattern of warming in the Gulf of Alaska and central Pacific regions, followed by expansion and movement towards the shore.
Past occurrences of warmer water patterns in the northern Pacific have been linked to larger and more destructive algal blooms.though, this event is not currently tied to an El Niño season. Forecasters are instead predicting a likely La Niña season for 2025/26.
The development of the Blob is being closely watched for potential impacts on weather patterns and marine ecosystems. NOAA continues to track its path and provide updates.