The National Weather Service has issued a heat advisory for the greater Washington area from 11 a.m. to 9 p.m. Wednesday.
Temperatures are expected to reach about 100 with a heat index value of 105 degrees due to high humidity. The weather service is also forecasting a 30 percent chance of thunderstorms during the day Wednesday and a 50 percent chance Wednesday night.
Looking later into the week, temperatures are expected to reach 94 degrees Thursday, with thunderstorms likely. On Friday and Saturday, maximum temperatures are forecast to fall into the mid-80s.
Metro is allowing riders to bring bottled water on board again Wednesday.
The weather service has cautioned local residents to drink plenty of fluids, stay in an air-conditioned room, keep out of the sun and check on elderly relatives and neighbors. Wear lightweight and loose clothing if possible.
Also, remembers never to leave small children or pets unattended in vehicles, where temperatures can rapidly climb to 130 degrees.