Junior Ashlee Powers led the way for the Sea Kings at Mt. SAC, finishing third in 18 minutes, 42 seconds.
Freshman Ellen Naruse was eighth in 19:02. Senior Devon Hoppe was 17th in 19:32, Kristen Rivera, who had been battling the flu, finished 20th in 10:45 and Shelby Perez was 24th in 20:02.
The CdM boys won the Pacific Coast League championship last week, their first league title in five years, Sumner said.
The Sea Kings were in a fast heat, the coach said, as four of the top 10 teams in the divisions competed in the race.
Austin Barvin (third, 15:44), Peter Morris (13th, 16:04), Blake Myers (18th, 16:14), Alex Turney (30th, 16:40) and first-time varsity competitor Reid Meckler (52nd, 17:05) helped CdM advance to next week's finals.
The CdM teams will vie to reach the state meet.
"We've been there 21 years in a row, so it's going to be a sad day if we don't make it," Sumner said. "We know exactly how to get there. We know what roads to take. But we still have to qualify. There's still work to do."
Sage Hill Division V
WALNUT — The Sage Hill School boys' and girls' cross country teams finished third and fourth in their heats at the CIF Southern Section preliminaries Saturday at Mt. San Antonio College to advance to Saturday's division finals.
The Lightning boys were paced by sophomores Brenna Hicks (seventh in 17 minutes, 8 seconds over the three-mile course), and Chris Andras (12th in 17:24).
Jack Percival (21st in 17:44), Alemar Brito (23rd in 17:46) and Dylan Thies (25th in 17:52 rounded out the top five for Coach Nate Miller's squad.
Sophomore Sophia Witte was 11th in 20:45 over three miles to pace the girls' team.
Naomi Granados (23rd in 22:20), Rannah Dabiri (24th in 22:23), Sophia Herzlinger (35th in 22:57) and Joelle Manula (36th in 22:58) also scored for the Lightning.
WALNUT — Costa Mesa High's Raquel Friedmann's finished 28th in her heat in Division IV at Mt. San Antonio College.
It was her final race of the season.
WALNUT — The Newport Harbor High boys finished sixth in their heat in Division II to end its season at the CIF preliminaries.
WALNUT — The Estancia High girls finished 14th in their heat in Division III to end its season at the CIF preliminaries.
— From staff reports