NOAA warns of warm, wet winter as record El Niño takes shape

The National Oceanic and Atmospheric Administration forecasts a winter marked by above-average temperatures and increased precipitation across much of the continental United States. This outlook stems from a powerful El Niño event that meteorologists describe as potentially the strongest on record. The warming pattern in the tropical Pacific is already altering global weather systems.

Ken Graham, director of NOAA’s National Weather Service, characterized the current conditions as a strong, if not historic, El Niño entering the winter season. He emphasized that these seasonal predictions provide a roadmap for cities to prepare for impacts and allocate resources. Graham noted that earlier and better decisions save lives by allowing communities to assess risks and mitigate them.

Josh Willis, a climate scientist at NASA’s Jet Propulsion Laboratory, uses the term Godzilla to describe the scale of the event. He explained that the warming water releases heat into the atmosphere, causing severe drought and wildfires in Indonesia and Southeast Asia. Simultaneously, the pattern kicks up hurricanes, storms, and high tides along the Pacific coast of the United States.

The West Coast has already felt the effects. In early October, a Kelvin wave raised sea levels and increased the risk of coastal flooding. This wave contributed to the extensive flooding associated with Tropical Storm Rachel. As of late October, another Kelvin wave was moving between Los Angeles and San Francisco, with several more expected through the fall and early winter.

Forecasters expect warmer temperatures in Northern California and above-average precipitation in Southern California. Higher snowfall is possible in parts of Nevada, the southern Rocky Mountains, and California’s San Bernardino Mountains. In the Pacific Northwest, temperatures will rise, but parts of the region may receive below-average precipitation, leading to a smaller snowpack.

The Southwest is already experiencing wetter conditions. Severe flooding in the Four Corners region forced rooftop rescues and evacuations in late October. Daniel Swain, a climate scientist at the University of California Agriculture and Natural Resources, attributed the severe thunderstorms to large amounts of moisture in the atmosphere. This moisture is driven by record-warm waters off the West Coast, which are linked to El Niño and a recent marine heat wave.

Despite the increased rainfall, Swain cautioned that the wetter conditions do not end the water crisis in the Colorado River basin. Lake Powell and Lake Mead remain at record low levels. He noted that the amount of water required to refill these reservoirs and maintain them at healthy levels is difficult to comprehend.

On the East Coast, forecasts indicate warmer temperatures and above-average precipitation. El Niño can strengthen nor’easters by pushing warm, moist air north. This combination can lead to coastal erosion and flooding similar to the record-setting year of 2023. Graham added that while El Niño favors a milder winter in the northern United States, it does not erase the risk of snow.

The South has the highest chance of above-average precipitation. Northern Texas may see snow, while Florida, southern Georgia, and South Carolina face the highest odds of above-normal rainfall. This follows an unusually quiet Atlantic hurricane season that produced only one named hurricane. In the Midwest, the Upper Midwest is expected to have a smaller snowpack, while drought conditions are expected to persist or worsen.

Jon Gottschalck, a meteorologist and branch chief for NOAA, said dry conditions in western Oregon and Western Washington are expected to improve. He expects drought conditions in those areas to potentially end. The combination of El Niño and long-term warming from fossil fuel emissions is driving these shifting weather patterns across the continent.