PHOENIX - Two teens went hiking at Echo Canyon Park during the hottest time of the day without enough water.  When they became sick, they used their cell phones to call 911.

It was a tricky rescue.  "The tricky part is the wind," said Officer Jim Lineham of the Phoenix police.

Cross winds made it difficult for Lineham to land the helicopter.  This was his fifth rescue of the summer.

"They were in a shady spot, but they were waiving at us," he said.

Both boys were dehydrated after hiking for a few hours when heat exhaustion set in.

"They just missed a turn..it's really easy to do," said Lineham.

20 rescue crews were called to the scene near 56th Street and Camelback Road to help.

Firefighters say the weather may have cooled down a bit, but triple digit heat is still dangerous.

"If you have doubts about going up a mountain like this with not enough water, then you shouldn't be up there," said Capt. Larry Nunez of the Phoenix Fire Department.

The teens were transported to an area hospital as a precaution and they're expected to be okay.  Their names were not released.