Thanks to Daniel for the following.
I'm not sure if it's true, but Dennis Smith, who has directed many NCIS episodes and is directing episode 13.22 "Homefront", has tweeted that he is filming the show in DC and that First Lady Michelle Obama is there too. While I have not heard anything about it, I don't have any reason to believe that this is not true. I would post it with a question mark in the post title.
Note: this is also the first time ever that NCIS has shot on location in DC. The show is set in DC but is filmed in LA.
News flash! In Washington to shoot #NCIS Gibbs with FIRST lady Michelle Obama
— Dennis Smith (@NCISDIR) April 9, 2016