I lived in Las Vegas for 15 years. My peach trees grew like crazy! Basil
exploded out of the ground. Mint takes over anywhere it finds water. But
squash? Eggplants? Peppers? I could never get them to survive July and
August. When the temp hit 120, half of my garden died and I eventually
gave up.

I've found that some shade cloth draped over the plants gives them enogh
protection to survive. It doesn't seem to be the temperature that does
for them, it seems to be the savageness of the sun's rays.

I've tried that, with limited success. I grew some tomatoes at the side of
the house where they were protected from the noon/afternoon sun, and one
year they grew like crazy! But I was never able to duplicate that, and the
next year they were their usual lackluster self. Some cool weather plants
grew well - beets, carrots, greens did well but you had to time your
planting carefully. In Vegas, we went from too cold to too hot very fast. If
it was a long cold winter followed by an early hot summer, your cold weather
stuff did not have time to mature before it got too hot. 100 degrees in May
is not at all unusual.

I know a lot more now then I did then. If I ever find myself in a climate
like that (I hope I never do!) I'm optimistic I might have better luck.