As Spring warms up into Summer and the humidity and heat start to really set in, it's good to remember that, like every other member in your family, you need to take extra care with your pet. You can become dehydrated and dangerously hot, which can result in falling unconscious at best, vital organ damage, or at its very worst, death. The same is true for your pets!
We tend to think of animals as hardier than humans, but the truth is, dogs and cats begin to experience heatstroke (hyperthermia, medically speaking) at the same internal body temperature as humans do — 104° F. Severe heatstroke begins at 105° to 106° F internally, as well. It might be more difficult for you to gauge temperature with smaller pets such as hamsters, but there's one rule of thumb to keep in mind. Always watch the heat index. Meteorologist uses the heat index value to discuss what the temperature is once humidity is applied; it's this balance of heat and humidity that are dangerous to the health of your pet and you.
If the heat index is 90° F, you need to be sure to take precautions to protect your pets. They won't be able to ask you to turn on the air conditioning or ask you for extra water, or even to tell you they're starting to feel ill. Your pets depend on you to responsibly monitor the weather and give them what they need to stay healthy and comfortable.