Coastal flood warning threatens record tides along San Diego County

Potentially record-breaking tides could flood low-lying coastal areas across San Diego County this week. The National Weather Service warned tides may reach 7.5 to 8 feet through Thursday, Oct. 29, threatening beaches, roads and property from Del Mar to Imperial Beach.

A coastal flood warning took effect at 5 a.m. Sunday, Oct. 25, and remains in place until 1 p.m. Thursday, the San Diego Union-Tribune reported. The warning covers San Diego and Orange County coastlines.

"The tallest high tides we've ever seen reached 7-feet 8-inches back in November 2015, and we could go even higher than that in the coming week," said Chandler Price, a National Weather Service forecaster, according to the Union-Tribune.

Price said the flooding will affect low-lying areas including Cardiff reef, near Solana Beach.

High tides will occur each morning, running 1 to 1.7 feet above predicted levels, according to the NWS. Times of San Diego reported that tides of 7.5 to 8 feet or higher are expected starting Monday, Oct. 26, morning. The Union-Tribune reported the threat spans Sunday through Thursday along the entire county coastline.

Two factors are driving the threat, according to the Union-Tribune. Tides run unusually high from October through January as Earth nears its closest point to the sun, and El Niño is warming the ocean, causing water to expand and rise. The sea surface temperature at Scripps Pier in La Jolla hit 73 degrees on Saturday, Oct. 24, roughly 8 degrees above average.

San Diego County beaches have experienced deep erosion for months from a combination of large high tides and waves generated by tropical storms, the Union-Tribune reported. Metrolink announced it will cancel rail service between Laguna Niguel/Mission Viejo and Oceanside from Monday through Friday because of the high tides, according to the Union-Tribune.

AlertSanDiego, the county's emergency information account, urged coastal residents to move away from the shoreline and low-lying areas, avoid crossing flooded roads or beach access points, and not drive through flooded roadways. The account warned: "Turn around, don't drown."

Along the coast, daytime highs will climb into the upper 70s to low 80s Sunday and Monday, running 5 to 10 degrees above normal, according to the NWS. Metrolink's Oceanside service suspension runs through Friday, Oct. 30.