Warmer and more humid weather has been a trend here in PA the last few years. It seems we go from winter, to a week of spring, then it jumps right into summer! I have noticed this more over the years because of my dogs having to be kept cooler earlier and longer in the spring and summer months. Mild winters have also been a challenge as it brings fleas and ticks out sooner than normal.
At the same time that Bentley bloated last year he also suffered from heat stroke. His temperature was 107 when I brought him to the vet, high enough to do long term damage to major organs. This all happened within fifteen minutes of being outside during the begining of a thunderstorm that was still miles away from our area!
Usually it is the humidity that causes more problems than the heat itself as dogs can't cool themselves efficiently. Their sweat glands are on the paws and nose so running around does not allow the sweat glands on the paws work as they should. Heat exhaustion is the body's way of trying to protect itself from loss of body fluids and salts.
Symptoms of heat exhaustion are heavy breathing/panting, and the skin inside the ears becomes flushed and red. Heat exhaustion may be taken care of by spraying the dog with a cool water bottle and placing him in front of a fan or putting the dog in air conditioning.
Heat exhaustion can quickly turn to heat stroke if the dog is not brought to a cooler area.
Symptoms of heat stroke Rapid panting, bright red tongue, red or pale gums, weakness, becomes wobbly/uncoordinated, vomiting, diarrhea, shock, and the body temperature reaches 105 or better. (Normal body temperature for dogs is 100.5 to 102.5.)
Use cool water not cold water as cooling the body too rapidly can cause other life threatening medical conditions. For very small dogs you will want to use luke warm water. Put the dog in front of a fan or in air conditioning. Do not immurse the dog in a tub of cool water and leave him in there as the dogs fur and skin will warm the water near the skin in effect make the body temp rise. Once the dog has been immursed in cool water you want to remove him, and check the temp. You want air to get to the body once you have used cool water so it can evaporate off of the dog. Make sure to get the belly and inner thighs. Check the temperature every five minutes and once it starts to go down stop the cooling process and dry the dog off but continue to monitor the temperature. Once the temp starts dropping continuing a cooling process can actually drop the temp too much causing more damage. When the temp starts dropping bring the dog to a vet.
Forcing the dog to drink water does not really help with the core body temperature, giving a few laps or spraying with a water bottle to keep the tongue and gums moist can help, but if you force him to drink and he drinks too fast you risk bloat as well as the dog inhaling it into the lungs.