Heat stroke is caused by extended exposure to high temperatures, and it can be life-threatening. If you're outside on hot days for any length of time, the Illinois Department of Public Health advises watching for these danger signs:

- headache

- red, dry face

- skin that is hot to the touch

- a body temperature of 105 degrees or higher

- a rapid pulse

- loss of consciousness (in extreme cases)

- seizures or an irregular heartbeat.

If you suspect someone has heat stroke, immediately get that person into a cool, shaded area and offer water. Run a cool bath or put ice packs on the head, neck, armpits, and groin area. If the person is delirious or losing consciousness, take him or her immediately to the hospital.