Hurricane Polo Swells To Reach Orange County Beaches: When Surf Will Be At Its Highest

ORANGE COUNTY, CA — Sunday is a day all eyes will be on the Southern California shoreline. With the incoming Kelvin wave slated to rise tides along the already embattered shoreline, the added swells generated by Hurricane Polo are expected to reach Newport Beach, North Orange County and all of Southern California late are expected to produce elevated surf, coastal flooding, and significant beach erosion on Monday and Tuesday, forecasters said Thursday.

Hurricane Odalys is also churning off central Mexico and could send a smaller southwest swell into Southern California waters as early as Thursday night.

"Still plenty of uncertainty next week as Polo and Odalys swirl off central Mexico," according to the National Weather Service. "In an odd twist, the two storms are actually slowly moving towards each other and this will present some tricky track issues that may not be resolved until late this weekend."

Most forecast models show Polo moving northwest before making landfall over central Baja California, while Odalys is expected to begin moving slowly north, according to the NWS.

A forecaster for Surfline.com told the Orange County Register that this is a "tricky track" forecast. "The most likely outcome an extreme-angled southeast swell early next week, building Sunday and the largest day on Monday," he said.

The incoming Kelvin wave, described by Andrew Leising, an oceanographer at the National Oceanic and Atmospheric Administration, is a higher sea level associated with warmer temperatures. Not a "true wave." Smaller Kelvin waves have "always happened. It just depends on what else is going on, if we pay attention or not," he told the Register.

Forecasters said there is "relatively high confidence" that Southern California will be affected by southerly swells, but "much less confidence" in the chances of rain, particularly with the latest forecasts favoring a Polo landfall somewhere in Baja California Sur.

Hurricane Odalys could send a smaller southwest swell into Southern California waters, while Polo is expected to generate a larger southeast swell beginning late Sunday and continuing through Tuesday.

"Polo's swell will produce elevated surf across exposed south facing coastlines," the NWS said. "High tides near 7 feet will peak in the late morning hours Monday and Tuesday. The combination of elevated surf and high tides will cause additional coastal flooding along some south-facing beaches.

In Orange County, the likeliest areas for flooding is North Orange County, areas around Seal Beach, Huntington Beach and Newport Beach. Forecasts are showing waves rising to 7 feet in some areas, with some 10-foot sets Monday. Huntington Beach waves could reach 10 feet on Monday.

The embattled Wedge Beach is susceptible to large waves and large-scale erosion, the Register reports.

Both Seal Beach and Newport Beach are rebuilding sand berms in preparation for the anticipated hurricane swell.

High tide Monday will be at 10:15 a.m., as beaches see a reach a 6-foot tide. Tuesday's high tide will be at 11:15 a.m.

The areas of greatest concern include the Peninsula and Belmont Shore in Long Beach, Avalon and Malibu, according to the NWS.

Forecasters said the most likely outcome would be shallow seawater flooding of low-lying walkways, parking lots and roads, along with significant beach erosion. Very localized damage to structures is possible in the most vulnerable areas.

There is a lower chance of more widespread and significant seawater flooding and structural damage, according to the NWS.

The weather service said there is a high chance that coastal flood advisories will be issued as soon as Friday for the Monday-Tuesday period.

Meanwhile, marine layer clouds returned to Southern California Thursday as onshore flow increased, sending temperatures down several degrees away from the immediate coast and as much as 10 to 15 degrees below Wednesday's levels in some areas.

Similar conditions are expected Friday, with cooler weather continuing through the weekend. Inland temperatures are expected to fall 5 to 10 degrees below normal, while coastal areas should remain slightly above normal, generally in the mid- to upper 70s.

Some forecast models indicate offshore flow could develop Tuesday and Wednesday, potentially producing a 10- to 15-degree warming trend. Forecasters said confidence in that forecast remains relatively low because of uncertainty over the tracks of the tropical systems.