Southern California is currently bracing for an extraordinary weather event as a large storm system impacting the Pacific Northwest sets the stage for significant wave activity along its beaches. This development, forecasted by the National Weather Service, stands out as the most prominent weather story for the region as 2023 draws to a close.
On Christmas Day, the Southland experienced clear skies and daytime temperatures in the mid to upper 60s. However, a noticeable change is expected with the arrival of the northern storm system, which will bring high clouds and a slight drop in temperatures to Southern California by Tuesday.
Despite the high pressure that is likely to ward off substantial rainfall, light rain might occur through Thursday in areas like Ventura County and along the Central Coast, though the impacts are expected to be minimal.
Contrastingly, the effect on surf conditions is anticipated to be much more significant. The National Weather Service predicts “moderately high surf” through mid-week, escalating to much larger waves from Thursday and into the weekend. The expected wave heights are considerable, with the Central Coast possibly seeing waves as high as 20 feet.
Los Angeles and Ventura counties might experience waves ranging from 10 to 15 feet, while in San Diego and Orange counties, waves could exceed six feet, accompanied by potentially dangerous rip currents. This larger, longer-lasting swell is set to bring widespread high surf conditions to northwest and west-facing beaches in all counties from late Wednesday night through at least Saturday.
This wave activity is not an isolated phenomenon but part of a broader trend linked to climate change. Research from UC San Diego’s Scripps Institution of Oceanography, using nearly a century of data, indicates that the average heights of winter waves along the California coast have increased due to the planet’s warming.
The study highlights that since the 1970s, there has been a 13% increase in average winter wave height in California, with a marked increase in the number of storm events producing waves over four meters (13 feet) in height.
The implications of growing winter wave heights are significant, especially in the context of accelerating sea-level rise due to climate change. Higher waves, riding atop rising sea levels, can bring more wave energy to vulnerable sea cliffs, flood low-lying regions, and damage coastal infrastructure during storms.
Additionally, the study points to the Aleutian Low, a semi-permanent wintertime low-pressure system near Alaska’s Aleutian Islands, which has intensified since 1970. This intensification corresponds with the observed increase in storm activity and intensity, providing further evidence of the changing patterns in the North Pacific Ocean.
This growing storm activity, driven by climate change and rising sea levels, adds a new dimension to the challenges faced by coastal communities in California, emphasizing the need for proactive measures to mitigate and adapt to these evolving environmental conditions.