The National Weather Service said the temperature would be in the 90s Monday and Tuesday, but was expected to drop into the 80s Wednesday and the high 70s Thursday and Friday. The normal high for this time of year is 77.
The Philadelphia Corporation for Aging Heatline will begin operating at noon Monday and continue until midnight. People concerned that they are having medical or other problems related to the heat can call 215-765-9040 for advice.
Special field teams from the city will conduct home visits, Schwarz said.
The elderly, people with chronic medical conditions such as heart disease, and those taking certain regular medications for mental illness are at greatest risk, the city said.
Pregnant women, small children, those who work in high-heat environments, and anyone engaged in strenuous physical activity also should be careful.
To avert heat-related illness, people should avoid working or playing outside. Those who must go out in the sun should wear a wide-brimmed hat or visor. Use air-conditioners or fans to cool indoor air. With fans, keep windows open to release trapped hot air.
Those taking regular medication should consult with their physicians because some medications cause an adverse reaction in hot weather, the city said.
Early-warning signs of heat stress include decreased energy, slight loss of appetite, faintness, light-headedness, and nausea. People experiencing these symptoms should go to a cool environment, drink fluids, remove excess clothing, and rest.
Serious signs of heat stress include unconsciousness, rapid heartbeat, throbbing headache, dry skin, chest pain, mental confusion, irritability, vomiting, diarrhea, muscle cramps, staggering, and difficulty breathing. People experiencing any of these symptoms should get immediate medical attention. While waiting for help, move the person to a cool area, remove excess clothing, spray with water, and fan the person. In an emergency, call 911.
Contact Miriam Hill at 215-854-5520, hillmb@phillynews.com, or follow on Twitter @miriamhill. Read the City Hall politics blog at www.heardinthehall.com.