First off, the hottest time of the day is not noon, despite what many people might think.

Noon is usually the pick, because that's when the sun is straight up in the air. But it takes time for the Earth to heat up, so the hottest part of the day in Phoenix is actually around 3 p.m.

So if noon's not the hottest part of the day, surely there's some kind of danger from the sun being directly overhead.

There is: UV radiation, the kind that causes sunburns.

Arizona is off the charts right now when it comes to intense UV exposure. The more direct the sunlight is, the worse the UV radiation.

In Phoenix, the worst UV radiation hits from 10 a.m. to 2 p.m.

We even verified when the most dangerous time is to be on the mountains. Phoenix fire says it's not the hottest part of the day, it's before and after work from 9 a.m. to noon and again from 6 to 8 p.m.

Phoenix fire says that's when most of the mountain rescues happen. Probably, they say, because people try to hike in the morning, but start too late. Then they try after work, but it gets too dark to come down.

As for the time of year that's the worst for rescues, it's not even the summer.

Phoenix fire says it's the month of March, when the snowbirds and spring training fans are here and try to hike above their ability.

So if you've been keeping track, Phoenix in the summer is dangerous pretty much from 9 a.m. all the way to 8 p.m.

So during the hottest months, just stay out of the sun as much as possible.