They bloom in mid to late March. This would be the tail end of it.
According to this, last year was early and 2013-15 were April 9th and 10th. I predict early bloom this year because of the warm weather. Just remember that DC is almost always 5ish degrees warmer than NJ.
http://www.nationalcherryblossomfestival.org/about/bloom-watch/
A couple other tidbits:
My favorite hotel in the DMV is Landsdowne Resort. Downside is that its way out in Loudon County VA (Leesburg), at least an hour from DC, less for the closest Metro stop. Great for golfing and three outdoor pools open in the summer. While the exterior says early 90s the interior has been recently updated. Not a bad place to stay if you are going to see NOVA sites like Manassas, Bull Run or Udvar-Hazy Museum, the larger version of Air and Space Museum.
My pick for best museum is Holocaust. It's well curated, it's set up to tell a compelling story and I've learned a few things I did not know about the Holocaust. Emotional and moving too.
My pick for the worst museum is American Indian (except for it's dining, one of the best museum food courts). Little if any telling of Native history, there is more of that in the bookstore than most of it's exhibits. Exhibits are usually focused on the contemporary, modern day tribal experience, a lot of tribal arts and crafts.
Udvar-Hazy Museum out by Dulles is a far better version of Air and Space mostly because it's large, spacious and not as mobbed with people as Air and Space is. Plus it has a Space Shuttle, a spy plane and a Concorde.
