NWS warns Sunday surf could top September's damaging waves Play

The big waves, high tides and coastal erosion arriving Sunday morning are expected to be more severe than the waves that walloped Malibu in early September, the National Weather Service said Saturday night.

In the words of the NWS office, in all caps: "THERE IS GROWING CONFIDENCE THAT THE EXPECTED COASTAL FLOODING IMPACTS ON SUNDAY MORNING FOR VULNERABLE SOUTH-FACING BEACHES OF LA COUNTY COULD BE THE MOST SIGNIFICANT WE HAVE SEEN SO FAR THIS SEASON, INCLUDING THOSE SEEN WITH MARIE."

Those Hurricane Marie waves, tides and surf caused sand to vanish from beaches along Malibu and Westward Beach roads on Sept. 10. A repeat is likely Sunday morning, the NWS said.

"The most likely areas for DAMAGING coastal flooding on Sunday morning will be vulnerable south-facing beaches due to the expected combination of very high level tide levels around 8 feet (including additive effect of low barometric pressure and onshore winds gusting to 15 to 25 mph), high surf of 5 to 8 feet, and light to moderate rainfall."

Saturday morning, the L.A. Harbor Tide Gauge reported a peak high tide of 7.7 feet, approximately 1.6 feet above predicted astronomical high tides. The very low atmospheric pressure, the Kelvin wave of water pushed up from the equator, and the warm, expansive ocean water are causing tides to run more than 19 inches above the lunar tides.

On top of that, swells from the remnants of Tropical Storm Rachel, new swells from Hurricane Simon off Baja, transoceanic swells from a hurricane south of the equator, and a giant supertyphoon near Japan are expected to combine into very bad news for Malibu.

Locally, the leading edge of moisture from Tropical Storm Rachel was moving into the coastal waters Saturday afternoon, with a 10 to 20 percent chance of thunderstorms across the local beaches of L.A. and Ventura counties.

A Coastal Flood Warning is in effect for the beaches of Los Angeles County — including the Malibu coast and Catalina Island — through 3 p.m. Sunday.

Damaging sea-water coastal flooding is likely through Sunday, especially near the Sunday morning high tide, forecast for 9:52 a.m. at 7.2 feet plus the 1.6 feet from the other pressures.

The official word from the NWS Saturday night: "A very complex series of swells from the south, west, and northwest will impact our coastlines into at least early next week."

"Energy from Tropical Storm Rachel, southern hemisphere swells, northwest swells, and local wind swells will add up with each other to produce the aforementioned coastal impacts. Please continue to monitor the forecast."