The National Weather Service in St. Louis has issued an excessive heat warning in effect from 1 p.m. Wednesday to 8 p.m. Saturday and includes Warren County.The excessive heat watch is no longer in effect. An excessive heat warning means that a prolonged period of dangerously hot temperatures and high humidity will occur. Nighttime conditions will remain warm and muggy, providing little chance for relief. This combination will create a dangerous situation in which heat-related illnesses are likely, especially for people who don’t have air conditioning.Heat index values are expected to be up to 113 due to temperatures in the upper 90s, and dewpoints in the lower 70s.Highs each afternoon will be in the mid to upper 90s.Dangerously high temperatures and humidity could quickly cause heat stress or heat stroke without precautions. Know the signs and symptoms of heat exhaustion and heat stroke. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency, call 9-1-1 immediately. The very young, the elderly, those without air conditioning, and those participating in strenuous outdoor activities will be the most susceptible.Car interiors can reach lethal temperatures in a matter of minutes. Young children and pets should never be left unattended in vehicles, under any circumstances. This is especially true when car interiors reach lethal temperatures in minutes.People who have properly working air conditioning should use it. People without air conditioning, should keep their living space well ventilated with fans, and try to take breaks from the heat in an air conditioned environments.People are advised to avoid poorly ventilated areas and prolonged work in the sun.Take extra precautions with outdoor work. When possible, reschedule strenuous activities to the early morning or evening, when temperatures may be cooler. Wear light weight and loose fitting clothing and drink plenty of water. To reduce risk during outdoor work, the occupational safety and health administration recommends scheduling frequent rest breaks in shaded or air conditioned environments.Heat advisory