Now that looks like cecal poop! I tend to worry (a lot)... so i just figure that it's REALLY unlikely that my chickens are always dying from some obscure disease :P
That doesn't really look like cecal poop... cecal poop is black and tarry. I am from California and i understand the hot weather. I have also seen this kind of poop with my chickens here in WV which is also quite warm... i personally would not worry, but you may want to research more :)