By Rachel Wulff

AUBURN (CBS13) — With triple-digit temperatures, we are already seeing heat-related rescues and fatigue for firefighters and people enjoying the outdoors.

“It was 103 degrees at 2:30 p.m.,” said one woman who was monitoring her heart rate and the heat with her Apple Watch.

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Hikers at Hidden Falls hit the trails despite the heat.

“I needed an afternoon workout,” said Leo Heuston.

Heuston is hardcore.

“I’ve got water, I’ve got first aid and snacks,” Heuston said.

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But even he knows his limits.

“I stay out less than half a day when it’s really hot like this,” he said.

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Not everyone was so prepared. Eric Cates was caught a bit unprepared on his bike.

“It was a beast coming back. I underestimated it,” said Cates. “I have a bunch of water stored in my car I thought I could go back, but it was probably an unwise decision.”

It can happen to the most seasoned bikers and hikers when the thermometer hits triple digit temps.

A San Diego couple had to be rescued from a trail there Monday afternoon after heat exhaustion set in. In Placer County, a hiker had to be rescued off a trail in Colfax after suffering heat-related symptoms.

“Even a healthy person can go down in this heat,” said Mike Mohler with Cal Fire.

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That’s why Cal Fire puts crews through special heat-related training.

“The first thing our wildland crews do is go for a hike in the morning, start to get acclimated. But it’s a year-round process,” he said.

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Planning and preparing before you are out on the trail is key. Cal Fire tells crews for every two water bottles, have a Gatorade to replenish electrolytes.