Temperatures exceeding 100 degrees shut down the Placentia Heritage Festival and Parade on Saturday when 60 people were stricken with heat-related illnesses.

Twenty people were taken to several local hospitals, Orange County Fire Authority Capt. Larry Kurtz said. They ranged from children to senior citizens and included parade participants and spectators.

Firefighters from OCFA, Fullerton, Brea, Anahiem and officers from the Placentia Police Department responded to the scene. The temperature was 100 degrees at 1:30 p.m.

At least 10 members of the Temescal Canyon High School marching band, from Lake Elsinore, had to drop out during the parade, experiencing dizziness and dehydration, said Lisa Brenenstall, who has a 16-year-old daughter in the band. One of them was taken to hospital.

The school quickly ran out of drinking water in the morning, and a few parents asked around the nearby neighborhood to get 40 additional gallons of water in jugs, Brenenstall said.

Just a couple of hours after the parade, Temescal Canyon and other marching schools went on to compete in a field show at nearby Valencia High School. Most of the members who dropped out from the parade returned and performed in the show.

“We rehearsed a lot during the past week, so I feel like everyone in this group has the will to push through,” said Alex Luna, a 17-year-old on the Temescal Canyon marching band.

At least five additional participants were taken to hospitals from the afternoon band show, OCFA Capt. Steve Concialdi said.

Two Orange County cities broke records on Saturday for the date’s highest temperatures. Santa Ana’s 103 degrees bested the 101 degrees recorded in 1991, said James Thomas, meteorologist at the National Weather Service.

Newport Beach reached 92 degrees, breaking the previous record of 90 degrees from 1939.

Yorba Linda reached 105 degrees; Anaheim 104; Lake Forest 100; and Huntington Beach 99.

In Laguna Niguel, an OCFA helicopter picked up three hikers suffering from heat exhaustion on Car Wreck Trail in Aliso and Wood Canyons Park around 12:30 p.m., Concialdi said.

A woman in her 30s was dehydrated while hiking along the trail, prompting her boyfriend to seek help, Concialdi said. OCFA firefighters were able to reach her on trail where they gave her water and Gatorade.

While leaving the trail, the firefighters came across two separate groups of teenagers who each reported they had female friends showing signs of heat exhaustion, Concialdi said.

The woman and two teenage girls were taken by helicopter to a nearby landing zone where they were treated by paramedics. One of the teenage girls was taken to Mission Hospital for treatment, while the other teen and the woman were released at the scene.

Temperatures today are expected to be in the mid-80s on the beaches and 90s for inland Orange County, Thomas said.

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