A severe thunderstorm warning and a heat advisory are in effect until Friday evening in Baltimore and across much of central Maryland, the National Weather Service announced.
The alert from the weather service’s Storm Prediction Center in Norman, Oklahoma means conditions are favorable for storms exceeding 58 mph winds and one-inch pieces of hail.
The warning is in effect until 5:30 p.m. in Baltimore City, southwestern Baltimore County, Columbia, Ellicott City and Glen Burnie, according to the National Weather Service’s Baltimore/Washington bureau.
Meteorologists recommend residents move to an interior room on the lowest floor of a building for their protection.
City police dispatchers described trees falling through the second floor of a home, motorists trapped on flooded roads, trees and downed utility poles blocking streets.
Baltimore Gas and Electric reported 291 households were without power just before 6 p.m. City crews received more than 150 service requests for downed trees, Mayor Brandon Scott wrote on Instagram.
The National Weather Service also issued a severe thunderstorm watch for Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil, Charles, Dorchester, Frederick, Harford, Howard, Kent, Montgomery, Prince George’s, Queen Anne’s, St. Mary’s, Talbot and Washington counties. The watch is in effect until 8 p.m.
“During the watch, people should review severe thunderstorm safety rules and be prepared to move a place of safety if threatening weather approaches,” the weather service advises.
The weather service issued the heat advisory until 7 p.m. for “dangerous heat and humidity” in much of Central Maryland Friday, with heat indices between 100 and 107 degrees.
“The combination of the high heat/humidity will lead to quite the unstable atmosphere,” the meteorologists wrote in their forecast discussion for the region.
“West-to-east storm development looks to occur mainly after 2PM before reaching the metro areas by late afternoon/early evening. Main hazards associated with any severe storms will be damaging wind gusts.”
A convergence of high and low pressure systems is causing a buildup of instability in the atmosphere, creating a line of thunderstorms across the region, the weather service said.
“Expect storms to die out this evening after heating ends ... with late night turning out dry and muggy again,” the meteorologists wrote in the online discussion.
Rain is in the forecast most of next week, but temperatures should dip down into the 80s after a cold front moves through Saturday, said Connor Belak, a National Weather Service meteorologist.
“It’s not going to be all day every day, but there are definitely rain chances almost daily next week,” Belak said. “Not too bad when it’s not raining. ... It definitely won’t be in the upper 90s next week.”