Veronica Johnson said an extreme heat wave will bring 101 degrees Thursday, 103 Friday and 102 on the Fourth of July across the D.C. region. The National Weather Service has a heat advisory in effect for the entire region from 11 a.m. Wednesday until 8 p.m., with an extreme heat watch covering most of the area through Friday.
Veronica Johnson forecast
Johnson said the heat wave will last potentially into Sunday, when the expected high is 94 degrees. She also said the Fourth of July heat index could run from 100 to 107 degrees, and even at 10 p.m. it could feel like 95 to 100 degrees.
Eileen Whelan said Thursday is shaping up to be one of the hottest days the D.C. area has experienced in years, with heat index values reaching as high as 112. The National Weather Service said conditions were dangerous because the heat index exceeded 100 degrees in some areas.
MedStar Baltimore heat illness
Dr. Sharon Swencki, an emergency physician with MedStar Baltimore, said people working outside, people with chronic illness, elderly people and people on some medications are more prone to heat illness. She said early heat illness often shows up as nausea and muscle cramping, especially among people working outside in the heat.
Most of the D.C. region is expected to stay dry, but isolated late-day storms could develop and produce damaging wind gusts. In Philadelphia, a heat emergency runs Wednesday through Saturday, with 50 cooling centers operating with extended hours, while Norristown canceled a Saturday parade because of the weather.
Fourth of July in the D
The holiday forecast leaves little nighttime relief, which means the longest stretch of danger may come after sunset rather than during the hottest hours of the day. For people without air conditioning and for anyone working outside, the practical step is to treat Wednesday through Sunday as a sustained heat event and to watch for early symptoms before they become severe.
