There's a heat advisory in effect today, and it's just going to get hotter with 105 degrees forecast for tomorrow.

The extreme temperatures, the hottest we've seen so far this year, can make it dangerous for those who are going to be outside for any length of time.

The hottest parts of the day are the afternoon and early evening, so if you can wrap up your outdoor activity in the early morning, it would be a good idea.

If you are going to be outside, you'd be well-served to take a few basic precautions.

Hiker Rich Robert is doing just that.

"I always hydrate myself and everything before I start up," he said. "I don't want to be on the news for getting hauled off the mountain."

Robert is right about hydration.

Water is a must. Be sure to drink plenty of fluids, and avoid caffeine and alcohol as they can contribute to dehydration.

"Dehydration can happen within just a matter of minutes," said Dep. Fire Chief Elio Pompa of the Glendale Fire Department

Stay in the shade as much as you can, and wear light-colored, loose-fitting clothing. A wide-brimmed hat will go a long way to keeping your head and body cooler. And don't forget the sunblock.

A few simple precautions might keep you from needing heat-related emergency care.

"Throughout the Valley, between the 20-something cities that are here, there are several thousand calls that go to a heat-related type of an illness," Pompa said.

The elderly, children and pets are the most vulnerable.

"Every year, firefighters respond to the calls that we don't like to hear, whether it's a drowning or a child that has been left inside of a vehicle," Pompa said.

The temperature inside a closed car that's not running, which means there's no air condition, can soar to as high as 160 or 170 degrees in a very short time, Pompa explained.