High surf and severe coastal erosion are now threatening beaches throughout Southern California, where emergency officials have issued urgent safety warnings. Hurricane Polo, which has weakened to a Category 3 storm, is moving west-northwestward and is expected to make landfall in Baja California Sur, Mexico, on Monday.

The system previously peaked as a Category 5 hurricane, with NOAA aircraft recording winds of 180 mph in the eyewall. Polo is the third Category 5 storm observed in the Pacific this season and is among the most powerful cyclones in decades. The storm already prompted port closures and class suspensions in southwestern Mexico, bringing sudden downpours and dangerous waves to the state of Colima.