Sonali Tiwary
Tropical Storm Rachel Flooding: Why Southern California Beaches Flooded
If you own or rent near the Southern California coast, Tropical Storm Rachel's flooding may have caught you off guard. Waves and elevated sea levels breached coastal defenses, and the storm's full passage was still unfolding as forecasts pointed to a possible landfall near the California-Mexico border.
Tropical Storm Rachel brought high surf and coastal flooding to Southern California this week. The Los Angeles Times reported flooding and erosion along beaches while the storm remained offshore, with a landfall near the California-Mexico border expected early Sunday. The National Weather Service issued coastal flood warnings, with surf of 5 to 7 feet and local sets up to 9 feet in the San Diego advisory area.
Property owners along south-facing beaches face structural undermining and saltwater damage to electrical systems. Photograph waterlines now, and check whether your insurance includes separate flood coverage. National Flood Insurance Program claims have their own deadlines, so check the current FEMA guidance for your situation.
Why did Rachel cause such bad flooding?
A coastally trapped oceanic Kelvin wave, a slow pulse of raised water that travels along the coast, was already lifting sea level before Rachel's swell arrived. Reporting at the time put the Kelvin-wave contribution at roughly 6 to 12 inches. Think of filling a bathtub before someone jumps in: the splash goes over the edge. The National Weather Service and the Los Angeles Times both discussed this mechanism.
What is still unclear
The exact tide observation, wave height at each location, and the engineering cause of any specific boardwalk damage have not been confirmed in the material reviewed. Do not treat earlier figures about tides being 18 inches above prediction or waves of 10 to 15 feet as settled.
What happens next
Coastal flood risks were forecast to extend through Sunday and into Tuesday in some areas, per the National Weather Service. Check the latest local advisory for your exact time window. Check back for updates.
