By David Shepardson
WASHINGTON (Reuters) -U.S. government offices in the Washington area closed early on Monday due to approaching thunderstorms as people across the eastern U.S. were warned of possible tornadoes, damaging wind and large hailstones before the end of the day.
The National Weather Service said more than 29.5 million people lived in an area from Alabama to western New York state where there was a risk of tornadoes before 11 p.m. ET.
The greatest risk was in the mid-Atlantic area including Washington, D.C. Some places could see wind exceeding 75 miles per hour and hail larger than golf balls, the NWS said.
More than 800,000 customers had lost power in the southern and mid-Atlantic states, according to tracking website PowerOutage.us.
The Federal Aviation Administration ordered departing flights grounded at airports in New York, Washington, Philadelphia, Atlanta and Baltimore because of thunderstorms. The FAA said it was rerouting aircraft around the storms as much as possible.
Libraries, museums, the National Zoo, pools and other municipal and federal services in the Washington area were also closing early. The U.S. Office of Personnel Management said federal employees had to depart no later than 3 p.m.
FlightAware, a flight tracking site, said more than 2,300 U.S. flights had been canceled, including 95 at Washington Reagan National Airport. Another 6,800 U.S. flights have been delayed.
(Reporting by David Shepardson; Additional reporting by Jonathan Allen in New York; Editing by Lisa Shumaker, David Gregorio and Cynthia Osterman)