A recent article in North Carolina Health News highlights the problems that older people may face when heat waves occur. Older human bodies (and probably also those of older pets and livestock) do not handle heat as well as younger folk, so they are more likely to suffer ill health when temperatures rise. This is especially true in cities where the urban heat island makes things even warmer. You can read more at https://www.northcarolinahealthnews.org/2018/07/10/rising-nc-heat-blasts-everyone-but-hits-those-over-65-harder/.