FYI, if you're wondering why there are street closures around Grand Central Terminal, it's because the FDNY, Con Edison and MTA are conducting a "full-scale exercise" between 7 a.m. and 2 p.m. today. Notify NYC says, "The exercise will simulate a steam release in Grand Central Terminal."
These streets are closed:: Vanderbilt Ave from East 42nd to East 46th and East 44th and East 46th streets between Madison Ave and Vanderbilt. Notify NYC reiterates, "There will be emergency personnel and equipment operating in the area. This is only an exercise." The public will not see the drill, as it's taking place in a closed area. And Metro-North riders will be reminded it's only a drill with the following announcement, "May I Have Your Attention Please. There is No Emergency in Grand Central Terminal. Metro-North Railroad is Conducting a Drill with New York City Emergency Service Agencies. Thank You."
In 2007, a steam pipe exploded near Grand Central, causing injuries and damage to buildings. A woman died from a heart condition while a young man whose truck was on top of the site of the explosion was seriously burned. Mayor Bloomberg called it a failure of the city's infrastructure.