With temperatures expected to be around 110 degrees on Sunday, technical rescued crews responded to a number of reports in just a couple hours of hikers feeling the effects of the heat across the Valley.
There was a single rescue in Scottsdale, for reports of an injured hiker, plus four in Phoenix for heat-related issues—all before 11 a.m.
Firefighters are asking hikers to only venture out in the earliest and latest hours of the day. And to be prepared.
"We encourage folks to take a hike and do it right," said Phoenix Fire Capt. Jake Van Hook. "Have on the proper footwear, have plenty of water, and as always, if you run out of water or when you get to the halfway point of your water, it's a great time to turn around. You need to have water coming back down as well."
At Camelback Mountain, a 33-year-old man experienced heat-related issues, including disorientation.
Phoenix technical rescue crews used a big wheel operation to get him off the Cholla Trail. He went to the hospital to be treated for an injured ankle in addition to the heat-related problems.
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A 43-year-old woman ran out of water on South Mountain and was experiencing vertigo, Phoenix fire said.
Phoenix and Tempe rescue crews reached the woman and started her on an IV. According to Phoenix fire, she was able to walk with assistance and did not have to go to the hospital.
Up north, at Deems Hill Recreation Area, crews helped two adults who became overheated and distressed.
Rescue teams from Phoenix, Glendale and Peoria responded to a mountain trail near Andrea Lane to assist. Both people were able to walk down the trail after they rested and hydrated.
Phoenix technical rescue crews also responded to the Phoenix Sonoran Preserve, where a 14-year-old girl hiking with her parents experienced heat-related issues.
Crews reached the girl using a 4-wheel-drive vehicle and assisted her in walking down the trail. She also won't be taken to hospital, according to Phoenix fire.
Crews responded near 7th Avenue and Carefree Highway.
In Scottsdale, technical rescue teams and air operations were working to remove an injured hiker from Sunrise Trail. Scottsdale fire said the hiker was stable.
This rescue was not immediately attributed to the heat.
Crews also responded to an area that borders the far southwest portion of South Mountain Park for reports of a man who ran out of water and felt weak.
Firefighters said they found the man with severe cramping and showing signs of dehydration. Rescuers used a big wheel to rescue him and sent him to a local hospital for further evaluation.