Let's hope autonomous cars like the heat.

Capitalizing on the area's opportunities for extreme temperature testing, Google announced Thursday that it is expanding its self-driving car testing program to Phoenix, Arizona.

"The Phoenix area has distinct desert conditions, which will help us better understand how our sensors and cars handle extreme temperatures and dust in the air," said Jennifer Haroon, head of business operations for the Google Self-Driving Car project. "Driving in new cities enables our engineers to further refine our software and adapt to these different environments.”

Google has four Lexus RX450h crossovers driving around Phoenix digitally mapping lane markers, traffic signals, curb heights, “keep clear” zones and more.

Phoenix is the expansion city in the U.S. for Google's self-driving car testing. After originating the tests in Mountain View, California, the tech giant later added Austin, Texas and then Kirkland, Washington to its list of trail run cities.

To date, Google's self-driving cars have clocked more than 1.5 million miles of autonomous driving. I hear if they drive another half million miles, they get a free submarine sandwich.

Either way, keep an eye out Arizonans, you might be soon sharing the road with a robot.

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