During a key portion of the webinar an earthquake with a preliminary magnitude of 5.8 struck near Washington, D.C., the U.S.Geological Survey said. The epicenter was in Virginia. The quake was felt in Philadelphia, Pennsylvania, New York, and on Martha’s Vineyard where President Barack Obama is vacationing. Cell phone service has been disrupted in New York City where parts of Manhattan have been evacuated. “Everybody was told to take the stairs,” Wolf Blitzer said, speaking live at 2 p.m. E.T. from CNN’s D.C. bureau.