Serious Eats - seriouseats.com

I love,love, love this recipe! Its just so darn refreshing!
Finely slice 1/2 a small red onion & over the top of that squeeze the juice of a lime. Let this sit for about 10 mins. and you'll find that the red onion will lose its bite.
Meanwhile combine 1/2 tub of feta cheese(crumbled), 1 tin of black pitted olives (drained), 1 small watermelon (cut into mouth size chunks) & 1/2 to 1 cup of finely cut fresh mint. Add the red onion and the the juice from the lime. I believe you'll be pleasantly surprised.

Central California, we here in Texas feel you. We have been dealing with heat year in/year out. Here are some tips:

Hydration is important. Multiple small snacks work better than big meals. Don't overlook replacing the salt you will lose when it gets hot and you are sweating.

Prioritize. Pace yourself. Some things you let slide when it is dangerously hot. Other tasks you have to allow more time for in extreme heat. Fans help a LOT. Air that moves takes 10+ degrees off.

Use your microwave rather than your oven. That rice salad suggested by thewrighttaste? Make the rice in the microwave.

If you have an outdoor grill, use that to cook meat in the morning and plan for several meals using the leftovers without heating up your house.

Finally, if you can get your hands on good fresh fish make ceviche. Serve that with some gazpacho and you'll do better than survive - you'll thrive!

Lots of water...I don't think anyone can say it enough. I tend to go with room temp, because I will get more into me that way. Also, I generally drink less coffee in the mornings in the summer, so there is always some left in the pot later in the day. I'll pour it over ice with a little sweetener, and a dribble of milk and chocolate syrup if I have it.

Rice salad - depending on how many of you there are, make your rice in the morning - jasmine or basmati adds a great taste. When it has cooled, toss with diced tomatoes, cucumbers with the peels left on but the seeds removed and diced, and sliced scallions. Toss with a vinaigrette.

A little less substantial is the "garden salad" we always had at home. We didn't grow lettuce, but it is filled with diced tomatoes, cukes, peppers and green onions. No dressing - the juices take care of it. A little grind of pepper is all I ever add at the end.

Don't forget the tomato or cucumber sandwiches. Fresh bread with mayo, or toast with butter...yum!

Moving away from places that get hot and humid! We've had highs of mid 80s and under all summer here, which SO beats the 90F+ in humid, muggy heat I suffered in back east.

I'm with mint juleps as well.

Gin and tonics are my favorite for something cool to drink while sitting on my patio.