Tides hit 8 feet as El Nino floods SoCal coast

Southern California coastal communities face further inundation this week as El Nino conditions push water levels to record highs. The National Weather Service extended flood advisories for all coastal counties through 2 p.m. Friday, a later expiration than the original 1 p.m. Thursday deadline.

Meteorologist Devin Black of the weather service’s Oxnard office reported that seawater has covered low-lying areas and reached the bases of some structures. Orange and San Diego counties, which previously held a severe flood warning, were downgraded to a coastal advisory through Friday afternoon.

Newport Beach and Long Beach have suffered the most damage. In Newport Beach, the Balboa area experienced widespread flooding, while Sunset Beach saw streets submerged. Pacific Coast Highway is closed in that area, and Caltrans plans to close portions of the road on Thursday. Long Beach remains a primary concern after being acutely affected on Thursday.

Tides are expected to reach 8 feet on Thursday morning before gradually dropping over the weekend. Black noted that while tides were high region-wide, the angle and magnitude of swells increased risk in San Diego and Orange counties due to their exposure to southwesterly winds. He described recent tides as being on the extreme end of the scale.

Scientists attribute the rising waters to a combination of factors. Ocean temperatures are elevated by human-caused climate change, an El Nino-fueled Kelvin wave, and a months-old marine heat wave. This heat wave has raised seawater levels by 1.25 to 1.8 feet above what would be expected from astronomical forces alone.

Mark Merrifield, director of UC San Diego’s Center for Climate Change Impacts and Adaptation, warned months ago that this event would likely produce the highest sea levels ever recorded on the California coast. He predicted that flooding along the Southern California coast would be a major issue for the winter season.

The weather service notes that even higher tides are expected around Thanksgiving, Christmas, and Martin Luther King Jr. Day. If a strong storm arrives during these periods, the result could be severe flooding similar to the historic storm of late January 1983. That event occurred during a strong El Nino and damaged many piers along the California coast.