Hermosa Beach is a beachfront city in Los Angeles County, California, United States. Its population was 19,506 at the 2010 census.The city is located in the South Bay region of the greater Los Angeles area and is one of the three Beach Cities. Hermosa Beach is bordered by the other two, Manhattan Beach to the north and Redondo Beach to the south and east.The city's beach is popular for sunbathing, beach volleyball, surfing, paddleboarding and bars. The city itself extends only about 15 blocks from east to west and 40 blocks from north to south, with the Pacific Coast Highway running down the middle. Situated on the Pacific Ocean, Hermosa's average temperature is 70°F in the summer and 55°F in the winter. Westerly sea breezes lessen what can be high summertime temperatures in Los Angeles and elsewhere in the county and help keep the smog away 360 days of the year.