X2 what Rock Island said. Water, Water Water. Keep it in the shade, make sure there is enough shade with a breeze for all the chickens at the same time. Also, the heavier fluffier chicken breeds have a harder time in the heat than the mediteranian breeds, like leghorns. I have heard of people freezing jugs of water and putting them out into the pens in the shade to help cool things down. I've never tried that, but it was something I heard. Were any of the flock panting from the heat?
Another thought on the hen that passed, is it possible she had heart failure? loud noises and lightening can scare chickens literally to death, especially if they have a problem to begin with. Just a thought.
Another thought on the hen that passed, is it possible she had heart failure? loud noises and lightening can scare chickens literally to death, especially if they have a problem to begin with. Just a thought.