Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke. The magnitude of anticipated heat, combined with oppressive warmth at night will lead to hazardous conditions, particularly for the elderly and those with pre-existing health conditions. Residents of the city of Chicago can call 3 1 1 to request well being checks for elderly friends or family members, or for information on finding the nearest cooling center. Stay cool, stay hydrated, stay informed. Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.