The National Weather Service has issued an excessive heat warning for the Morongo Basin. Daytime temperatures through Wednesday are expected to range from 109 to 115. An excessive heat warning means that a prolonged period of dangerously hot temperatures will occur. Heat-related illnesses, such as heat exhaustion and heat stroke, will be possible. People most vulnerable include those who are spending lots of time outdoors, those who do not have air conditioning, young children, the elderly, and those with chronic ailments. Residents are advised to drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Car interiors can reach lethal temperatures in a matter of minutes.