A heat dome that has been parked over the southwestern United States throughout most of July is starting to expand eastward, and millions of people in the mid-Atlantic will soon feel the effects.
The temperatures in Washington, D.C., and Baltimore are predicted to top out around 100 degrees Fahrenheit at the end of the week, the hottest it has been in both cities in years.
“It has not yet reached 100 in either city this year,” said AccuWeather Senior Meteorologist Bill Deger. “In fact, it has not even gotten into the upper 90s yet in Washington.”
The most recent 100-degree temperature reading in D.C. was seven years ago when the city experienced triple-digit heat for three consecutive days, ending on Aug. 15, 2016. The mercury in Baltimore reached this benchmark more recently when back-to-back 100-degree readings occurred on July 19-20, 2020.
“When factoring in the sunshine and high humidity levels, the AccuWeather RealFeel™ Sun Temperature will easily exceed 100 degrees each day in both cities and perhaps could rise as high as 110,” said Deger. “This will make some outdoor activities dangerous for extended periods of time.”
A heat emergency, an alert that goes into effect when the temperature is predicted to reach or surpass 95 degrees, will likely be issued by District officials. When a heat emergency is declared, dozens of cooling centers across the city are opened to the public.
“Residents and visitors should take extra steps to beat the heat by staying in the shade or air-conditioning, drinking plenty of water and visiting a cooling center,” the District of Columbia said on its website.
The Baltimore City Health Department may follow suit with a Code Red Extreme Heat Alert, a similar warning to the heat emergency in Washington, D.C.
The heat will not be as intense over the weekend, but it could still pose the risk of heat-related illness for people planning outdoor activities Saturday and Sunday.
The temperature in both mid-Atlantic cities is forecast to top out in the upper 90s Saturday with AccuWeather RealFeel™ Sun Temperatures above 100 F.
A more noticeable downturn in temperatures is likely to unfold during the start of next week, as a dip in the jet stream will knock down temperatures, with highs predicted to be in the upper 80s, around the historical average for late July.
Produced in association with AccuWeather