Update April 5, 2018: According to the National Park Service, the Yoshino cherry trees on the Tidal Basin reached peak bloom today, and best viewing of them should be during the next 4-7 days, depending on the weather. Singers desiring to see the blooming trees are advised to visit the Tidal Basin in the early morning or early evening (before dark), and/or on Friday or Monday to avoid the peak crowds. Note that inclement weather (rain, possible snow, and cold temperatures) is predicted for Saturday, April 7.
The blooming of the famous and beautiful -- but transitory -- Yoshino cherry trees around the Tidal Basin and Jefferson Memorial in Washington, DC usually reaches a peak during the first week of April, although there is considerable variation from year to year. Singers attending the Potomac River Convention during its usual first-Sunday weekend in April usually are able to see the blossoms in at least partial bloom, and in some years are able to catch them in full bloom.
Starting in late February or March, the National Park Service horticulturist in charge of the trees issues predicted peak-bloom periods (see Web links below). The definition of "peak bloom prediction dates" seems to be imprecisely explained and may be misinterpreted by the news media. (The term sometimes means the range of dates in which the Peak Bloom Date (first day of at least 70% open blossoms) is expected to fall. Some media may misinterpret this range of dates to mean the precise dates in which the blossoms will be at their peak.) It is best to visit the cherry blossoms very early in the morning or late in the afternoon or early evening, to avoid the crowds.
Other species of cherry trees, as well as flowers such as daffodils and some tulips, are usually in bloom during this period also, providing multiple delights to those visiting Washington for the Potomac River Convention. Kwanzan cherry trees around the Tidal Basin, Hains Point, and East Potomac Park, usually bloom around two weeks after the Yoshino cherry trees.
For latest information on blooming dates, consult the Bloom Watch Web page of the National Park Service.
The 2018 National Cherry Blossom Festival will take place from March 17 to April 15. Consult the Festival's Web site.