City health officials are warning residents to take precautions as Baltimore is expected to experience a stretch of 90-degree heat starting Wednesday.
Temperatures could reach the mid-90s, with a heat index near 100 degrees and an unhealthy air quality, officials said.
"Individuals should stay indoors in air-conditioning as much as possible and be sure to stay hydrated with water today," said Dr. Leana Wen, Baltimore health commissioner, in a statement.
Young and elderly residents are most at risk for heat-related illnesses, Wen said.
The health department recommends residents drink water instead of alcohol and caffeine. Children and pets should not be left alone in closed vehicles and residents should avoid outside activities, instead seeking air-conditioned environments.
Temperatures in the 90s are expected into the weekend, meteorologists said. A "Code Orange" air quality warning is in effect through Friday, meaning the air can hurt sensitive groups, such as the elderly, children or those with heart or lung ailments.
The signs of heat exhaustion and heat stroke include lightheadedness, nausea, and confusion, as well as hot, dry, flushed or clammy skin.
Residents are asked to call 911 if experiencing such symptoms. More hot weather information is available at the department's website at health.baltimore.gov.